Maryland Amphibian and Reptile Atlas
(MARA)
Training Handbook
Maryland Department of Natural Resources
and
Natural History Society of Maryland
February 2010
Handbook compiled by: Rachel Gauza and David Smith
Maryland Amphibian and Reptile Atlas Handbook - ii
Table of Contents
Introduction to the Maryland Amphibian and Reptile Atlas ........................................... 1
Foreword .......................................................................................................................... 1
Background ..................................................................................................................... 1
History of the program ......................................................................................... 1
Purpose.................................................................................................................. 2
Volunteer role and involvement ......................................................................... 2
Basic unit of coverage – Grid system ............................................................... 3
General information ............................................................................................. 4
Instructions: Data Collection and Data Submission ........................................................ 5
Study Design ................................................................................................................... 5
Survey season ...................................................................................................... 5
Survey effort .......................................................................................................... 5
How data are collected ........................................................................................ 6
Working with USGS Quadrangle (Topographic) Maps ........................................ 8
Obtaining a quadrangle map .............................................................................. 8
Tips and considerations for map use ................................................................ 8
Land Access and Legal Issues .................................................................................. 9
Land access .......................................................................................................... 9
Collecting and possessing amphibians and reptiles in Maryland ................. 9
Atlasing Ethics .............................................................................................................. 12
Proper handling of amphibians and reptiles .................................................. 12
Vouchering and retaining of live and deceased herpetofauna.................... 13
Disinfection procedures ..................................................................................... 14
What to Bring with You While in the Field............................................................. 15
Essential items .................................................................................................... 15
Other helpful items ............................................................................................. 15
Considerations for the Field ..................................................................................... 16
Venomous snakes: sensible precautions ....................................................... 16
Protecting yourself from ticks ........................................................................... 17
Other considerations.......................................................................................... 17
Filling Out the Data Sheet .......................................................................................... 18
Block data sheet ................................................................................................. 18
Species verification ............................................................................................ 19
Habitat classification system ............................................................................ 21
Data Submission Procedures ................................................................................... 23
Tricks of the Trade: Amphibian and Reptile Ecology Basics ...................................... 24
Salamanders, Lizards, and Snakes – Oh, my!...................................................... 24
Amphibians.......................................................................................................... 24
Reptiles ................................................................................................................ 25
Age Isn’t Just a Number ............................................................................................. 26
When to record larval (“L”) ................................................................................ 27
When to record juvenile (“J”) ............................................................................ 27
Where and How Do I Start? ................................................................................................... 28
How to Find Amphibians and Reptiles ................................................................... 28
Maximizing success: Where and how to search ........................................... 29
Road cruising ...................................................................................................... 35
Surveying for sea turtles ................................................................................... 36
Verification Procedures .............................................................................................. 37
Photodocumentation .......................................................................................... 37
Audio recording and sonogram preparation .................................................. 42
References ................................................................................................................................. 43
Acknowledgements ................................................................................................................. 43
Glossary ..................................................................................................................................... 45
Suggested Reference Materials ........................................................................................... 48
Maryland Amphibian and Reptile Atlas Handbook - iv
Introduction to the Maryland Amphibian and Reptile Atlas
Foreword
Thank you for your interest and participation in the Maryland Amphibian and Reptile Atlas
(MARA)! The purpose of this document is to provide instruction and written standard operating
procedures for data collection as part of the Maryland Amphibian and Reptile Atlas.
Background
History of the program
The Natural History Society of Maryland (NHSM) and the Maryland Department of Natural
Resources (MDNR) are conducting a five-year atlas of the amphibians and reptiles of Maryland
starting in January 2010 and ending in 2014. The project will map the distribution of all
amphibians and reptiles within the state, using mostly volunteer help. Planning for the statewide
atlas began in summer 2008. It was decided that a pilot study should be used to test survey
methods and quantify the effort needed to effectively and efficiently document herpetofauna
effort before launching the effort statewide. Data collection was limited to Anne Arundel County
and occurred from spring through late fall 2009.
Amphibians and reptiles, collectively known as “herpetofauna” or “herps,” have roamed the
earth for over 300 million years. While today’s collection of herpetofauna pales by comparison
to the diversity and abundance of these creatures during their heyday, their persistence to the
present day is a testament to their overall success. However, the increasing challenges that
amphibians and reptiles face – in no small part resulting from human-induced causes such as
habitat loss, introduced species, over-harvesting or collecting, and environmental pollution –
raises concerns for their continued success and even survival. Worldwide declines in amphibian
and reptile populations have been occurring at an accelerated rate over the past twenty years,
threatening many species with extinction.
There is a recognized global, national, and regional need to determine the scope and severity of
the problems and causes of declines in herpetofauna populations. Observed declines highlight the
need for documenting current amphibian and reptile populations in Maryland. In the 1930s and
1940s, the NHSM published distributional surveys of reptiles. However, it was not until 1960
that the curator of the Department of Herpetology at the NHSM, John E. Cooper, published a
paper on the distribution of amphibians and reptiles for the state. In 1969, Herb S. Harris Jr.
published the first distributional survey of every amphibian and reptile known to occur in
Maryland. Harris updated the survey and range maps in 1975. Although distributional data have
been collected dating back to the 1930s, no systematic and replicable survey of all herpetofauna
has been conducted in Maryland.
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Purpose
The general purpose of MARA is to systematically document the present distribution of
amphibians and reptiles throughout Maryland using a grid-based system. The current amphibian
and reptile atlas will update the work that was done by Harris in the 1970s. Information gained
during this atlas effort will establish a baseline for future efforts to detect change in statewide
distributions. Understanding patterns of change at the statewide scale is necessary for land
managers, regulators, and citizens to make choices to conserve the herpetofauna of the state.
Volunteer role and involvement
This project relies nearly exclusively on volunteers to conduct fieldwork and document the
roughly 90 species of amphibians and reptiles known to occur within the state.
Each county is assigned at least one volunteer county coordinator (provided in the appendix of
this document). The principal roles of the county coordinators are to:
1. Recruit and motivate fieldworkers
2. Act as a liaison between fieldworkers and the statewide atlas coordinator and steering
committee
3. Provide technical assistance to fieldworkers (such as providing training or aid in species
identification)
4. Keep track of progress and coverage within the county
5. Assist steering committee with data verification
County coordinators will direct observers to cover specific geographic areas that will serve as the
basic unit of area covered (See: Basic Unit of Coverage – Grid System). Observers will work to
document the presence of the amphibian and reptile species within these geographic units of
area. Volunteers can select quads by indicating the nearest towns or areas of interest to the
county coordinator.
 All MARA volunteers must fill out and send in the data sheet and record
their time involvement in the project.
 Materials for distribution to land owners and other interested parties are
provided in the appendix of this document.
The participation and enthusiasm of volunteers is critical to the success of MARA. Please note
that fieldwork is strenuous by nature. All participants should be aware of the physical demands
and associated risks when conducting MARA activities. There is no volunteer age specification
associated with this project.
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Basic unit of coverage – Grid system
The atlas project is conducted on a grid-based geographic scale using U.S. Geological Survey
(USGS) 7.5-minute quadrangle (quad) maps equally divided into six blocks of approximately 10
square miles each. Within each quad, blocks are referenced by their directional orientation
(Northwest = NW, Northeast = NE, Center-west = CW, Center-east = CE, Southwest = SW,
Southeast = SE). An example of the numbering is shown in Figure 1. Blocks that overlap
counties will be assigned in their entirety. Blocks that overlap other states will only be covered
within the limits of Maryland.
Figure 1. Example of quad block numbering system. Six blocks compose one USGS quadrangle.
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There are 260 quads in Maryland, each named after a major town or geographic feature on the
map. Quads that encompass multiple counties will be assigned to the county containing the
greatest portion of the quad. This grid system is the same one used by the Maryland and District
of Columbia Breeding Bird Atlas (BBA) Project. MARA will only cover portions of grids within
the state of Maryland; the BBA covered the portion of atlas blocks that occurred within
neighboring states.
General information
For more information about MARA or any information presented in this handbook, please
contact:
Natural History Society of Maryland
PO Box 18750
Baltimore, MD 21206-0750
atlas@marylandnature.org
Maryland Department of Natural Resources
Wildlife and Heritage Service
580 Taylor Avenue, E-1
Annapolis, MD 21401
A map of Maryland Counties and list of County Coordinators are provided in the appendix.
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Instructions: Data Collection and Data Submission
Study Design
Survey season
Atlasing can be done at any time during the year that amphibians and reptiles are active.
Herpetofaunal activity will generally begin and end earlier in the eastern part of Maryland than
in the western portion. Therefore, it may be possible to encounter a species in the lower Eastern
Shore starting in January and not document the presence of that same species until April in the
western mountains.
Different species of amphibians and reptiles will be more easily detected during different times
of the year. Some, such as amphibians that breed in seasonal pools, will be most easily
documented during their migrations to breeding ponds or immediately after egg-laying. As
indicated above, this generally begins quite early in the year, often with the first warm rains.
Other, more terrestrial species may be active in the spring and fall, but difficult to find during the
heat of the summer. And for other herpetofauna, particularly snakes, activity is greatest during
the summer months.
It is important to plan surveys throughout the year to
maximize your chances of encountering as many different
amphibian and reptile species as possible.
Amphibians and reptiles are ecothermic (“cold-blooded”) animals, meaning that their internal
temperature is regulated by the ambient environmental temperature. Therefore, searches are
generally most successful later in the day when temperatures have warmed sufficiently for herps
to become active. However, many amphibians and reptiles may be encountered at any time of the
day within protected refugia by turning over cover objects such as logs or rocks. Still other
species, such as vernal pool-breeding amphibians, generally move to breeding ponds under the
cover of darkness. Some frogs, toads, and snakes may become active at night, particularly after
or during warm rain events.
More detailed information is provided later in the handbook (See: How to find amphibians and
reptiles). Calendars of Peak Herpetofaunal Activity (phenologies) for specific groups of species
will be provided as an addendum to this handbook.
Survey effort
Within each of the 23 counties in Maryland, the number of possible amphibian and reptile
species present ranges from less than 50 to greater than 60. Lists of the potential amphibians and
reptiles within each county in Maryland are provided in the appendix. Based on this county list,
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most Maryland atlas quads should have at least 30 species of amphibians and reptiles. Some
could exceed 60 species while those with considerable open water or urban areas may contain
fewer than 30 species.
 Observers should attempt to document at least 25 species per quad and
10 species per atlas block.
 A minimum survey time of 25 hours per quad should be spent over
the five year atlas.
Many species will be encountered within the first several outings to the quad. As you approach
the 25 species per quad and 10 species per block threshold, it may become more difficult to add
new species; however, don’t give up! Be sure to cover all available habitats within the
quad/block and use the search techniques described in this handbook (See: How to find
amphibians and reptiles). Plan to visit quadrangles throughout the year, at different times of
day, and in different conditions. Optimal times will vary with species, habitat, and time of year.
Once the 25 species per quad and 10 species per block thresholds have been reached, you can
continue to add new species to your quad/block, but a useful rule of thumb should be
approximately 30 hours of effort to get 30 species for the quad. Once this threshold has been
met, more time should be spent atlasing in other quads so that statewide coverage can be
obtained within the five-year survey period.
How data are collected
Survey in any and all suitable habitats (See: Habitat classification system). Searches include
actively looking for amphibians and reptiles (e.g., walking/searching habitat, turning over cover
objects such as rocks and logs, etc.) as well as more passive approaches (e.g., listening for
calling frogs and toads, cruising / road surveys). The time a fieldworker spends engaged in these
activities is to be recorded (See: Filling out the data sheet). Incidental or opportunistic reports
(i.e., encounters with individuals while not actively searching for amphibians and reptiles) will
also be included in the atlas, as will any dead herpetofauna encountered. All reports, even those
outside of assigned quads and in a different county, are to be submitted. Submit any and all
herp sightings.
Species documentation will be reported on standardized data sheets, one each per block per year
(See: Filling out the data sheet). Two levels of documentation confidence are possible for
detected species:
1. Species that are observed or heard only will be considered “reports”
2. Species observations supported by verifiable evidence (photographs, recordings,
vouchered specimens) will count as “verified records.”
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On the data sheet, an asterisk appears beside the name of each amphibian and reptile species that
requires verification before the report can be accepted as a verified record. Verification is
encouraged for all other species, but is not required (See: Species verification)
The verification form is provided in the appendix.
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Working with USGS Quadrangle (Topographic) Maps
Obtaining a quadrangle map
Each county coordinator will have a copy of the inclusive quadrangle maps to distribute to
volunteer quad leaders for their use in locating suitable habitats within each block.
Free electronic (.pdf) versions of USGS topographic maps can also be obtained by visiting
http://store.usgs.gov and using the Map Locator tool.
1. Click the Map Locator link (in left navigation bar area)
2. In search field, type: “Maryland” and click “Go”.
3. Zoom or pan to see your Quad Name and click on it
4. When the red balloon marker appears, click on it
5. Click on the Download link that matches the Quad Name and save the file
To divide the quad map into the six atlas blocks:
1. Measure half-way across the quad map from east to west and draw a line down the
middle of the map from north to south.
2. Locate the four crosshairs (+) on the map. Two crosshairs are located 1/3 of the way
down from the top of the map, and two crosshairs are located 1/3 of the way up from the
bottom of the map. They are about six inches in from the sides of the map.
3. Draw two parallel lines from east to west through the two sets of crosshairs.
4. Older versions of quad maps do not have the four crosshairs, so measure the length of the
map from north to south and subdivide it into three equal lengths. Draw two east-west
lines dividing the map into three equal subdivisions.
5. When completed, the quad should be divided as in Figure 1.
Tips and considerations for map use
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The scale of the print copies provided to County Coordinators is 1” = 2,000 feet, as
indicated by the scale on the map.
Contour lines represent elevations.
o The closer the contours, the steeper the slope; an absence of contours indicates the
ground is relatively level.
o V-shaped contour lines indicate flow and are often associated with streams /
stream valleys. The point of the “V” is oriented upstream / uphill.
The majority of quad maps have not been updated since the 1970s and landscape features
may have changed dramatically.
Fieldworkers are encouraged to use other maps and aids (e.g., ADC index maps, Google
Earth, aerial images) in conjunction with USGS quad maps.
Visit the USGS website for more information on how to read and interpret topographic maps:
http://egsc.usgs.gov/isb/pubs/booklets/usgsmaps/usgsmaps.html
http://edc2.usgs.gov/pubslists/booklets/symbols/index.php
Maryland Amphibian and Reptile Atlas Handbook - 8
Land Access and Legal Issues
Land access
Respect landowner rights! Participation in this project does not allow you to trespass on private
land – permission must be obtained to access private land. It is illegal to trespass and you do
NOT have the right to step foot on private property without permission from the landowner.
Land owned by a company or organization (e.g., CSX Railroads, Baltimore Gas and Electric,
Washington Suburban Sanitary Commission, etc.) is also considered private land and legal
permission must also be obtained before entering and conducting MARA activities.
The appendix includes a Maryland Amphibian and Reptile Atlas Letter to Landowner and
Landowner Release Form. A Windshield Sign is also provided for display in your vehicle.
Before conducting atlas survey work on private property, the landowner release form should be
completed by the property owner. Please be respectful of the wishes of private property owners
and be sure to leave the property as you found it.
Surveying on public lands (such as those owned by the Maryland Department of Natural
Resources or County parkland) requires that you obey posted property rules (e.g., park hours,
parking and access restrictions) as well as those set forth by the land manager. The Maryland
Department of Natural Resources will announce the project to park and state land managers, but
it is the responsibility of the fieldworker to make contact with the individual land manager and
discuss any intentions. In addition to preventing any rule violations, working with the land
manager may help the fieldworker to locate potential survey areas and allow access to areas
during peak herpetofauna activity.
 Remember: MARA fieldworkers are considered the “general public” and
do not receive any special exemptions from Maryland Law.
A discussion of legal issues pertaining to the collection of Maryland herpetofauna and collection
permit requirements is presented in the Vouchering and retaining of live and deceased
individuals section of the handbook.
Collecting and possessing amphibians and reptiles in Maryland
The Maryland Department of Natural Resources adopted permitting regulations concerning the
possession, breeding, and sale of reptiles and amphibians native to Maryland in 1993. Generally,
a permit is not needed to look for, pick up, hold, photograph, etc. any native Maryland
herpetofauna as long as it is immediately released where captured. You may NOT trap without a
permit. Trapping includes any method that relies on the use of a device to restrict the movement
Maryland Amphibian and Reptile Atlas Handbook - 9
of an animal and does not allow it to move freely about the environment and come and go on its
own. Examples of trapping methods that require a permit from the State of Maryland include
installation of drift fences, pitfall traps, funnel traps, and conducting electrofishing surveys.
The use of artificial cover or “sucker boards” is not considered trapping and thereby does not
require a permit. However, land access rules and other considerations (e.g., illegal dumping
regulations) still apply.
Additionally, there are restrictions to the number of live individuals or remains of individuals
that may be collected and possessed. Maryland law allows for the collection and possession of a
limited number of certain reptile and amphibian species from the wild without a permit. Species
are placed on three different lists (A, B, or C) depending on their conservation status.
Number of individuals of each species that may be collected and possessed:
 List A: No more than four individuals of each species
 List B: No more than one individual (with some exceptions)
 List C: None
For more information about Maryland’s amphibian and reptile regulations
and lists, please visit http://www.dnr.state.md.us/wildlife/captive.asp.
Under no circumstances should live or deceased individuals or remains of the following (List C
fauna) be removed from the location where found or retained (Table 1).
Table 1. List C herpetofauna identified by MDNR. These species may not be possessed, bred, or sold and may
only be held in accordance with a Scientific Collection Permit or an Endangered Species Permit issued by the
Department of Natural Resources.
Reptiles
Amphibians
Bog Turtle (Glyptemys muhlenbergii)
Common Mudpuppy (Necturus maculosus maculosus)
Northern Map Turtle (Graptemys geographica)
Eastern Hellbender (Cryptobranchus alleganiensis alleganiensis)
Loggerhead Sea Turtle (Caretta caretta)
Jefferson Salamander (Ambystoma jeffersonianum)
Kemp's Ridley Sea Turtle (Lepidochelys kempii)
Eastern Tiger Salamander (Ambystoma tigrinum tigrinum)
Green Sea Turtle (Chelonia mydas)
Wehrle’s Salamander (Plethodon wehrlei)
Leatherback Sea Turtle (Dermochelys coriacea)
Green Salamander (Aneides aeneus)
Atlantic Hawksbill Sea Turtle (Eretmochelys imbricata imbricata)
Eastern Narrow-mouthed Toad (Gastrophryne carolinensis)
Eastern Spiny Softshell (Apalone spinifera spinifera)
Mountain Chorus Frog (Pseudacris brachyphona)
Northern Coal Skink (Plestiodon anthracinus anthracinus)
Barking Treefrog (Hyla gratiosa)
Eastern Smooth Earthsnake (Virginia valeriae valeriae)
Carpenter Frog (Rana virgatipes)
Rainbow Snake (Farancia erytrogramma erytrogramma)
Northern Scarletsnake (Cemophora coccinea copei)
Timber Rattlesnake (Crotalus horridus)
Copperhead (Agkistrodon contortrix mokasen)
Note that no non-native amphibians or reptiles are to be released into the wild.
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More information on the regulations and a permit application may be obtained online at
www.dnr.state.md.us/wildlife/captive.asp or by writing, calling, or e-mailing:
Wildlife Permit Coordinator
Maryland DNR – Wildlife & Heritage Service
580 Taylor Avenue, E-1
Annapolis, MD 21401
410-260-8540
Violations of these regulations or permit restrictions can result in fines,
permit revocation and/or confiscation of animals, and is a misdemeanor under
Maryland Natural Resource law.
Please keep in mind that many herp species are endangered, threatened, rare, or declining.
Individual animals and their associated habitats must be respected and protected if populations
are to persist. It is best to take only photos and leave animals and habitats as you found them.
Harvesting and collection for the pet trade and other purposes are a major threat to herpetofauna
species; please be mindful when sharing findings and locations with entities outside of MARA.
Maryland Amphibian and Reptile Atlas Handbook - 11
Atlasing Ethics
Proper handling of amphibians and reptiles
Care and discretion should be used when handling amphibians and reptiles. Only handle an
animal if it is needed to make a positive identification and is safe to do so. Remember that
handling can cause stress, injury, and even mortality to amphibians and reptiles.
Please abide by these general procedures:
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When possible, try to photograph the animal in the field with the least amount of
handling possible.
 Photodocumentation procedures and tips are provided in the handbook.
Do not handle dangerous herpetofauna (e.g., snapping turtles, large or venomous snakes).
 A net, snake hook, sizeable stick, or similar tools can be used to facilitate capture.
Always use wet hands that are free of lotions, chemicals, etc. to handle amphibians.
Use a clear plastic bag or other container to aid in viewing herpetofauna and taking
photographs, particularly for larval and early life stages.
Clasp small individuals within both hands.
Hold large frogs at the pelvis with legs fully extended to prevent injury and fractures.
 This restraint technique should prevent the frog or toad from kicking and twisting.
 Apply only gentle pressure/resistance – take care not to squeeze too hard.
Do not grab salamanders or lizards by the tail.
 Although the tail can be regenerated, tail autotomy creates potential for infection and
loss of an important fat reserve.
Support snakes at multiple points along the body.
 Gentle pressure can be applied behind the head of the snake to reduce the potential
for a bite.
 Do not handle an agitated snake.
When capturing a snake is necessary, place in a pillowcase to reduce stress to the animal.
Lift or roll cover objects towards your body.
 If the cover object is particularly heavy, make sure herps are clear from underneath
before returning the cover object to its original position.
 If a herp was removed, return it so that it is oriented facing the cover object so that it
may return on its own.
Amphibian eggs should not be handled unless it is absolutely necessary to obtain a
picture.
 If that is the case, simply place hands gently under the eggs mass and keep them
suspended in water.
 Return egg mass exactly as it was encountered.
 Using an umbrella or other method of shading is recommended to reduce glare on the
eggs when capturing a photograph.
Do not disturb reptile nests or hibernacula.
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Vouchering and retaining of live and deceased herpetofauna
The collecting, killing, and preserving of amphibians and reptiles is not encouraged.
Photographic vouchers should be the main technique for the verification process. If live
individuals are captured for positive identification, release them as soon as possible to the
location of collection. Maryland law restricts the species and numbers of amphibians and reptiles
that may be taken from the wild, and no herp should be retained for greater than 30 days
(See: Collecting and possessing amphibians and reptiles in Maryland)
 The utmost humane treatment of animals should be utilized when conducting
MARA fieldwork.
 Photographic vouchers should be utilized whenever possible.
 As long as photographs of key features are captured, that is all that should be
needed for positive identification (see Photodocumentation).
Remains of organisms can be retained as part of the verification process if a photovoucher
cannot capture the diagnostic features needed to determine the species. Any remains should be
taken to the County Coordinator as soon as possible. All vouchers should have an
accompanying voucher label with the following information: Date, Quad, Block, Site Name,
Lat/Long Coordinates (if known), and Collector. A map marked with the location of collection
may also be submitted, and should be if GPS coordinates are unavailable.
In order to maintain the condition of the specimen, please consider these procedures and discuss
methods with your County Coordinator:
 Any voucher that is freshly dead or in the decomposition process (i.e., fleshy parts still
intact), should be transferred to a refrigerator or freezer or preserved using formalin or
ethanol, if available.
 Snake skins should remain dry and can be stored in a ziplock bag.
 A turtle shell with scutes intact may be shellacked to retain its quality, though that is not
required.
Remember to abide by the guidelines outlined in the Collecting and possessing amphibians and
reptiles in Maryland section of this handbook.
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Disinfection procedures
Background
Chytridiomycosis, ranavirus, and other diseases are among the growing threats to amphibian
populations. Respiratory and other infections also pose a major risk to turtles and other reptiles.
Chytrid fungus (Batrachochytrium dendrobatidis), in particular, has been identified as the cause
of decline and extinctions of hundreds of frog species worldwide. Like other invasive organisms,
Chytrid spreads easily; it is transferred from amphibian to amphibian as well as in water and on
damp materials. Therefore it is critical to disinfect boots, gear, and any items that come in
contact with rivers, streams, wetlands (especially seasonal pools), and moist leaf litter.
How to
The disinfection procedure consists of soaking or rinsing boots and all equipment in a 10%
bleach solution for at least one minute. Equipment with a smooth surface can be scrubbed with a
scrub brush using a 10% bleach solution. Wear lug sole boots only– felt sole boots/waders are
major disease vectors and will not be treated under this disinfection protocol. After soaking
and scrubbing have been completed, rinse with freshwater. The disinfection procedure can be
easily accomplished with two spray bottles – one with a 10% bleach solution and one with
freshwater. It is easiest to prepare these at the beginning of your field day and leave them in a
vehicle before moving on to another site.
Skin that comes in contact with herpetofauna or water during search activities should be cleaned
with alcohol-based hand sanitizer as part of the disinfection procedure. Use plastic bags only
once per field day – they can be disinfected and re-used for the next visit.
Note: Please be conscientious when disposing of bleach solutions so not to disturb and
pollute any freshwater habitats (particularly seasonal pools).
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What to Bring with You While in the Field
Essential items
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Data sheets
Verification forms
Maps – Quadrangle (with blocks marked), ADC Map Book, Aerial Images
Pencils
Field guide(s) and taxonomy handouts
Identification letter / letter to landowners
Landowner release form
Digital camera
Tape recorder, cellular phone, or similar recording device (to record hard-to-identify frog
calls and provide species verification)
□ Thermometer (to record air temperature for gray treefrog and Cope’s gray treefrog call
vouchers)
Other helpful items
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MARA handbook
Windshield sign
GPS unit
Rubber boots / hip waders
Flashlight or headlamp
Binoculars or spotting scope (for basking turtles)
Hand lens or magnifying glass
Polarized sunglasses (for reducing glare in aquatic habitats)
Dip net
Ziplock bags or clear viewing containers
Pillowcase (for temporarily holding snakes for photovouchering and/or positive
identification)
□ Snake hook, long stick, or similar tool (to aid in turning over objects)
Do not forget to disinfect boots and gear between sites!
(See: Disinfection Procedures)
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Considerations for the Field
Venomous snakes: sensible precautions
There are only two species of venomous herpetofauna in Maryland; both are snakes: timber
rattlesnake (Crotalus horridus) and copperhead (Agkistrodon contortrix). While the copperhead
can be found throughout the state, the timber rattlesnake is only known to be found from
Frederick County west and within an isolated population in Baltimore County. A bite from these
two snake species is painful and potentially life threatening. Medical treatment should be
sought immediately if bitten. Also, bear in mind that a bite from any organism, venomous or
not, has the potential for infection and other complications.
The following precautions should be followed to protect against snakebite:
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Learn to identify copperheads and timber rattlesnakes by sight.
When atlasing within areas where these snakes might be found, be cautious when placing
hands and feet.
Wear suitable clothing (e.g., long pants and heavy boots).
Never attempt to pick up living or dead copperheads or timber rattlesnakes. A bite from a
juvenile can still contain venom and requires medical treatment.
Take photographs or view individuals from a safe distance.
If investigating a dead specimen for positive identification, use a long stick when moving
the snake.
The timber rattlesnake and copperhead are pit vipers (family Viperidae, subfamily Crotalinae).
Pit vipers are identified by the heat-seeking pit between each eye and nostril. Additionally, pit
vipers differ noticeably from the non-venomous snakes in Maryland (family Colubridae) by
having vertical pupils and a single row of subcaudal (anal) scales. Illustrations of these features
are found in Figure 2.
Venomous
(Pit vipers; Family: Viperidae,
Subfamily: Crotalinae)
Non-venomous
(Colubrids; Family: Colubridae)
Vertical pupil
(and modified scale structure/ heat-seeking pit between
eye and nostril)
Round pupil
Single subcaudal scales
Divided subcaudal scales
Figure 2. Comparative features between venomous and non-venomous snakes in Maryland.
Maryland Amphibian and Reptile Atlas Handbook - 16
Protecting yourself from ticks
Ticks may carry Lyme disease and other diseases transmittable to humans. The best protection is
prevention. To prevent tick bites, wear protective clothing (e.g., pant legs tucked into socks, long
sleeves, etc.) and use chemical repellents. However, be sure to keep these repellants off hands
and skin that come in contact with amphibians. Check your clothing and body regularly while
in the field and upon returning from the field.
Seek medical treatment if you receive a tick bite, particularly if the tick is attached for greater
than 24 hours, and you experience any of the following symptoms of Lyme disease: Flu-like
symptoms (chills, fever, headache, lethargy, muscle pain), skin irritation or rash resembling a
bulls-eye, body-wide itching, joint inflammation, and stiff neck.
If you are bitten by a tick, it is advisable to save the tick on a piece of scotch tape or in a vial to
be taken to your doctor for identification and testing.
Other considerations
Conducting fieldwork may involve hazardous terrain and exposure to the elements.
Plan ahead for the weather and dress accordingly. Be aware of any allergies or medical
conditions of others conducting searches with you. It is advisable to carry a first aid kit that
contains basic essentials as well as an emergency supply of Benadryl. Have plenty of fresh
drinking water handy as well.
Remember that handling amphibians and reptiles increases your exposure to bacteria, so clean
hands frequently. Alcohol-based hand sanitizer is recommended as part of the disinfection
procedure.
Maryland Amphibian and Reptile Atlas Handbook - 17
Filling Out the Data Sheet
Block data sheet
The block data sheet (located in the appendix) is the most important aspect of the atlas project
and should be completed carefully to allow the accurate documentation of species. It represents
the accumulation of all amphibian and reptile observations for one person (the “observer”)
within a single block per year. If more than one person accompanies the observer during a
search, this will be reflected in the “# of people” column for each site visit.
 Fill out one data sheet per atlas block per year. Do not put data from two or more blocks
on one data sheet.
 If you are in the field with multiple people, only one person should be responsible for filling
out the data sheet from the trip. Please avoid duplication of hours on the data sheet.
 The use of a pencil is preferred on the data sheet to allow changes to age, evidence, and
verification codes as appropriate. Under no circumstances should water-soluble pens be
used.
 Take data sheets into the field as you survey and fill them out at the site. If you are unsure of
the quad or block number, determine this information at the conclusion of the field day.
The data sheet is comprised of two pages. The first page includes a title block (Figure 3) for
recording the year, name of atlaser responsible for that data sheet, quad name, block (place an
“X” in the appropriate block), and document ID number (assigned by the computer during
online data entry for data tracking0 purposes in the database).
Maryland Amphibian and Reptile Atlas Block
Data Sheet
YEAR: one year only
(one sheet per year
per block)
OBSERVER: Enter the name of the
atlaser responsible for the data sheet
QUAD NAME:
USGS 7.5 minute quadrangle
 Mark only one block (1/6
of a quad) with an “X”
BLOCK: (X)
NW
NE
CW
CE
SW
SE
Document ID:
(assigned by computer during data
entry)



Figure 3. Title block portion of MARA block data sheet example: Line-by-line instructions.
The remainder of the first page (Figure 4) is to be used to record information about each atlas
outing. This information includes the date, location (within block), total number of atlasers
conducting search in your group that day (including the observer) and effort for active searching.
The start and end time and total time spent searching for amphibians and reptiles is necessary as
a measure of effort for analysis of population trends. If you do not use military time to record
your start and end times, please include am/pm notations. Also, if your nocturnal searches extend
Maryland Amphibian and Reptile Atlas Handbook - 18
beyond midnight, please include the date that you started your search, rather than the ending
date. Record hours to the nearest quarter interval (i.e., 0.00, 0.25, 0.50, 1.00, 1.25, etc.).
Herpetofaunal observations outside of active searches will be noted as “incidental.” No hours
should be recorded for incidental observations since time was not spent actively searching. These
incidental observations can occur while conducting other activities unrelated to herp atlasing in
which amphibians and reptiles are observed. For opportune sightings, please note the precise
location of the observation so that the report or record can be attributed to the appropriate atlas
block if not known.
Coverage
Date
Location within Block
Patuxent NWR – BGE Wetland
03Mar2010 Mitigation Site
Patuxent NWR – Visitor Center
26Jun2010 Parking Lot
Active Search Time
# People
4
1
Start
End
Hours Incidental?
2115
0130
(9:15 pm) (1:30 am) 4.25
N/A
N/A
0.00
No
Yes
Figure 4. Example of coverage portion of MARA block data sheet using Laurel Quad, Block 4 (CE). Each
outing and incidental record is a separate line.
The second page of the data sheet is used to record all herpetofauna species observed in the
block. Record the same quad, block, year, and observer information as on the front of the
document. The remainder of the page includes a list of the 90 amphibian and reptile species
found in Maryland. Species for which more detailed verification is required are indicated with an
asterisk (See: Species Verification in the following section). Below the list of species found in
Maryland is space for “other” herpetofauna. Examples of other herpetofauna include exotic
species found in the wild or species with an uncertain distribution within the state. To the right of
each species name are three columns to provide more detailed information about the observation.
These columns represent “age,” “evidence,” and “verification”, respectively. Specific codes
corresponding to each column appear at the bottom of the data sheet page. Only one code is
needed per species, but feel free to include all appropriate codes.
Fieldworkers / atlasers are strongly encouraged to keep their own notes as well should any
follow-up be needed upon data submission.
Species verification
As indicated in the Study design section, observations will be treated either as a report or as a
verified record depending upon the level of documentation provided. Verification is needed to
confirm the identity of the species, such as species that look alike or are difficult to identify, or to
obtain exact location information for rare, threatened, or endangered species. Some level of
verification is required for all species (e.g., if the age of the species is either eggs or larval).
Maryland Amphibian and Reptile Atlas Handbook - 19
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Verification can be in the form of a photograph, an audio recording, or voucher
(shed skin, dead specimen).
For non-asterisked species, verification need only be done once for the quad.
A separate verification form (provided in the Appendix) is required for each
observation of all asterisked species.
Verification is required for all early life stages of amphibians (eggs and larvae).
The verification form includes space for reporting the following information:
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Species observed
Date of the observation
Specific location (atlas quad, block, and site location including lat/long coordinates)
Names of all observers and contact information for the person submitting the form
Number, age, and sex of the specimen
Description of the specimen
Description of the occupied habitat
Directions to the location (attach a copy of quad or ADC map with the location marked)
Notes on behavior of animal, length of time observed, or other pertinent details
Photovoucher (all vouchers will need to be presented to the county coordinators along
with the copy of the verification form).
For most amphibian and reptile species a photograph should suffice in providing
verification of the species. It is important to capture key/diagnostic features for a
positive identification (see photodocumentation procedures).
In addition to visual encounters, frog and toad species presence can be detected by listening for
the calls of advertising males. Audio recordings are useful for identifying and verifying species
of frogs and toad and can be collected in the field using many different devices designed to
capture sound, including digital cameras or camcorders, tape recorders, or more sophisticated
recording equipment. Species verification for calling frogs can be accomplished by collecting
audio recordings of a breeding chorus or individual frogs. An audio recording is mandatory to
distinguish the two gray treefrog species, as they can only be separated in the field by differences
in call rates.
When recording calling frogs and toads, you must document the time and air temperature in
the field when the recording was made. Record the temperature about one meter above ground
(away from body, vehicle, or other heat source). Temperature should be collected in the shade if
recording during the day. Please note that temperature data should not be retrieved from the
internet or other source. Other weather conditions (excluding temperature) as well as moon phase
can be recorded from the newspaper or online weather source.
Maryland Amphibian and Reptile Atlas Handbook - 20
Habitat classification system
A description of the habitat within which a verifiable species was found must be recorded on the
verification form. The following is a list of the various habitat types found within Maryland that
should be searched for herpetofauna:
Terrestrial Habitats:
- Deciduous forest – forest in which 75% or more of the stand is composed of deciduous
species (i.e., trees with flat leaves rather than needles, with the exception of Bald
Cypress). Major forest types include oak-chestnut-hickory, maple-beech-birch, and elmash-cottonwood.
- Coniferous forest – forest in which 75% or more of the stand is composed of coniferous
species (i.e., trees with needles and cones, typically referred to as “evergreen” trees).
Examples include pines, cedars, hemlock, and firs.
- Mixed forest – forest containing both coniferous and deciduous species with neither
group composing more than 75% of the stand.
- Recently logged / Disturbed forest – forest with obvious human modifications (other than
changes limited to trails). Examples include stands with timber harvesting, clear cutting,
or mining activity.
- Shrub thicket - shrub-dominated landscape typically occurring along streams but also
adjacent to lakes and beaver flooding.
- Cultivated field – fields of row crops or other produce that are actively farmed, tilled, and
maintained.
- Pasture – Agricultural area occupied by and managed for livestock.
- Grassland / Old field – open areas not currently used for agriculture or other purposes;
most of the vegetation consists of grasses and herbaceous species but may include a
scattering of small shrubs or trees (largely open canopy).
- Garden / Lawn – Grassy or planted area within residential zone.
- Rock outcrop – exposed rocks and slopes above the surface of the surrounding land.
Rock outcrops are primarily found in mountainous or hilly areas west of the fall line and
tend to be embedded within larger ecosystems such as hardwood forests. Examples of
this habitat include, cliffs, talus, quarries, rock slides, and ledges.
- Talus – Large deposits of loose rock found at the base of hills and along hillsides.
- Beach / dune – Coastal zone along an estuary or ocean. The deposits behind a beach
where the wind has moved beach material inland is a dune.
Aquatic Habitats:
- Vernal / Seasonal pool – a shallow body of water isolated from surface water that
undergoes periodic drying. These can be natural or man-made and may or may not
support fish. Examples include isolated depressions in the landscape such as sinkhole
ponds, low swales, road ruts, and ditches. Delmarva Bays are also included in this habitat
classification.
- Bog or Fen – freshwater, herbaceous wetland with no inlet or outlet. Bogs are acidic and
consist of a floating mat of peat; woody vegetation is scarce. Fens are open, herbaceous
Maryland Amphibian and Reptile Atlas Handbook - 21
-
-
-
-
wetland fed by perennial groundwater discharge; standing water is less than 2 inches in
depth.
Shrub swamp – wetland with greater than 25% cover of woody species that are less than
6 m (20 ft) in height; remaining area may be open or contain herbaceous vegetation;
contains few or no woody species over 6 m (20 ft) tall; standing water may be present.
Wooded swamp – wetland with greater than 25% cover of woody species that are greater
than 6 m (20 ft) in height, standing water may be present.
Marsh – treeless wetland, but may be bordered by trees. Predominant vegetation may
include cattail, Phragmites, sedges, rushes, and other emergent species. Indicate whether
freshwater or brackish salt marsh (as determined by land use setting and vegetation
classes).
Stormwater basin – a man-made depression or structure used to treat the quantity and
quality of stormflow runoff; includes dry or wet detention ponds, bioinfiltration
areas/biofilters, vegetated swales, and infiltration trenches. May or may not be part of a
storm drain network.
Drainage ditch – an area draining agricultural, residential, or commercial land that can
retain standing water or moisture.
Gravel / Borrow pit pond – a body of water filling a man-made gravel pit.
Lake / Pond – a body of water completely surrounded by land. Lakes are classified as
large (10 acres or greater) while ponds are small (less than 10 acres).
Seep / Spring – small headwater areas fed exclusively by groundwater. Seeps typically do
not flow while springs flow intermittently or constantly.
Stream / Brook – a flowing body of water with a current confined within a bed and
stream banks. Smaller than a river and may or may not be fed by smaller tributaries.
River – a large body of water flowing in a definite course or channel fed by converging
tributaries that empties into an ocean, lake, or other body of water. While some are
shallow with rocky bottoms, most have relatively large, deep channels and are steepsided.
Estuary / Open water – a semi-enclosed coastal body of water fed by rivers and streams
and connected to open ocean. Estuarine systems include open bays, tidal rivers, and salt
marshes characterized by varying salinities.
Land use:
- Agricultural – land managed for grazing or cultivation.
- Rural – area outside larger and moderate-sized cities consisting of farms, ranches, small
towns, and unpopulated regions.
- Suburban area – multiple houses and/or businesses with surrounding lawns and other
landscaped areas.
- Urban area – multiple houses and/or businesses primarily surrounded by buildings and
paved areas.
Maryland Amphibian and Reptile Atlas Handbook - 22
Data Submission Procedures
Completed atlas block data sheets and species verification forms should be turned in to the
county coordinators or entered online, once available, no later than November 30 of each year.
When the online data entry portal is completed, additional details on data submission will be
provided.
Verification forms should be submitted within two weeks of the observation to allow county
coordinators to assist with the verification and log the record. This is especially important for
rare, threatened and endangered species, to ensure that the information is distributed to
appropriate conservation agencies as soon as possible. Verification forms must be turned in
for asterisked species or the record will not be included in the final distribution maps or
other project products.
It is also strongly encouraged that volunteers submit monthly summary reports of hours
spent during active searches and number of species by atlas block so that county
coordinators can assess the level of effort being expended, and offer suggestions or support for
more effective atlas coverage where necessary.
Notify the County Coordinator as soon as is practical if an unknown herp is encountered. Take a
photovoucher, record the date and location in the block, and make note of habitat type where
found to assist with identification. Please report any malformed or mass mortality of amphibians
and reptiles to the County Coordinator as soon as possible in case follow-up action is needed.
Maryland Amphibian and Reptile Atlas Handbook - 23
Tricks of the Trade: Amphibian and Reptile Ecology Basics
The key to successful fieldwork for this project is proper identification of the amphibians and
reptiles encountered. There are many excellent field guides available to assist with the
identification of species. A list of the most useful field guides and other resources are provided
later in this document.
Salamanders, Lizards, and Snakes – Oh, my!
Although amphibians and reptiles are collectively grouped as “herpetofauna”, there are some key
differences between the two groups.
Amphibians
Amphibians, such as frogs, toads, and salamanders (in Maryland):
1) Have four limbs.
2) Have moist, glandular skin.
3) Lack scales and claws.
Most amphibians spend at least part of their lives in water habitats such as flowing streams,
seasonal pools, or other wetland types and respire subcutaneously (through the skin) to some
degree. The eggs of amphibians lack a hard outer covering and must be laid in water or damp
places. Most amphibians hatch as aquatic larvae with gills or spiracles. As amphibians grow into
adults, most species develop lungs which they use to breathe, and are capable of living both on
land and in water. Some salamanders never develop lungs and breathe entirely through their skin.
All amphibians respire through their skin to some degree.
Salamanders (order Caudata) possess a tail and two pairs of relatively similar-sized limbs.
Costal grooves (Figure 5) are usually present along the side of the body and mark the position of
the ribs. Salamanders also usually have a distinct neck that separates the head from the body.
Some salamanders have aquatic larval stages while others hatch into miniature adults that are
terrestrial. Aquatic larvae will have external gills that are most visible when the larva is fully
submerged in water.
Figure 5. General features of salamanders (order Caudata).
Species with an aquatic larval stage will have visible external
gills.
Distinct neck separating head from
rest of body
Costal grooves
Maryland Amphibian and Reptile Atlas Handbook - 24
There are five families and 22 species of salamander in Maryland. There is an array of habitat
preferences and morphological characteristics within each of these families and even among
subgroups in the same family.
Frogs and Toads (order Anura) look very different depending on life stage. Adult anurans in
Maryland do not have a tail and have hind legs longer than the front legs that are adapted for
jumping. The body is relatively short and there is no distinct separation of the head from the rest
of the body. The larval or tadpole stage is entirely aquatic – during this stage, anurans possess a
tail, develop relatively short legs, and have a spiracle for breathing. Tadpoles with legs can be
distinguished from salamander larvae by the lack of a discernable neck, the lack of external gills
and presence of a spiracle, and the presence of distinctly longer back limbs than the front limbs.
There are five families and 20 species of anurans in Maryland. Like salamanders, there is an
array of habitat preferences and morphological characteristics within each of these families. Both
frogs and toads are anurans. True toads (family Bufonidae) have thick, relatively dry, warty skin,
and enlarged glands in the shoulder region called parotoid glands (Figure 6). Unlike most frogs,
toads tend to move in short hops rather than large leaps. Note that spadefoot toads are not true
toads and are in the family Pelobatidae, characterized by the sickle-shaped spade on the inside of
each rear foot and vertical, elliptical pupils.
Figure 6. Parotoid glands
diagnostic of true toads
(family Bufonidae).
Parotoid glands
&
warty skin
Reptiles
Reptiles such as turtles, snakes and lizards:
1) Are covered with scales, shields, or plates.
2) Have claws on their toes (not applicable to snakes).
Reptiles use lungs to breathe, and generally lay eggs in terrestrial habitats. The eggs of reptiles
have a thick, hard shell that protects the developing embryo from moisture loss, especially on dry
land. Some snakes give birth to live young.
Reptiles and amphibians can often be found together, but reptiles (other than turtles and aquatic
species of snakes) tend to prefer drier environments, while moist-skinned amphibians need to
remain near aquatic, wetland, or damp forest habitats. Even primarily aquatic turtles and snakes
utilize dry areas to bask.
Turtles (order Testudines) are reptiles with a shell that covers at least part of the dorsum and
venter. There are five families and 19 species of turtles in Maryland, including sea turtles. Most
species can be identified by the shape, patterning, and scute characteristics of the shell.
Maryland Amphibian and Reptile Atlas Handbook - 25
Turtles fill a variety of ecological niches. Some, like the eastern box turtle, are primarily
terrestrial, while others, like sea turtles, spend nearly their entire lives in water with the exception
of coming ashore to nest. Some turtles can occupy any body of water or wetland, while others,
like the bog turtle, have very specific habitat requirements.
Snakes (order Squamata, suborder Serpentes) are limbless reptiles with scaled and elongated
bodies. All snakes lack external ear openings and eyelids and have long, forked tongues. There
are 29 different varieties of snakes in two families found in Maryland. Two Maryland species,
the copperhead and timber rattlesnake, are in the viper family (Viperidae). The remaining species
are in the family Colubridae, which is the largest snake family in the world.
Refer to Venemous Snakes: Sensible Precautions for how to distinguish Maryland’s vipers
from non-venomous snakes.
Lizards (order Squamata, suborder Lacertilia) have moveable eyelids, an external ear opening,
two well-developed lungs, and a fused lower jaw. Although legless forms do exist, all species of
lizards found in Maryland have legs.
There are six species of lizard in three families found in Maryland. The four species of skink
(family Scincidae) are characterized by smooth, small, and flat scales that produce a smooth and
shiny appearance. There is one species of spiny lizard (family Phyrnosomatidae), the eastern
fence lizard, which is characterized by its rough, keeled overlapping scales that project
backwards. Finally, there is one species of whiptail (family Teiidae), the eastern six-lined
racerunner, that is characterized by large rectangular scales and large keels on the tail that are
rough to the touch.
Age Isn’t Just a Number
As mentioned above, some amphibians have aquatic larval stages. Other amphibians, as well as
many reptiles, hatch from eggs directly and may or may not closely resemble the adult of the
species.
MARA asks for life stage to be recorded when logging a species in a block. Only one is required,
but you are encouraged to record every life stage that is present, separating each by a comma.
Refer to the data sheet for life stage codes.
Photographs and/or accurate descriptions of early life stages (e.g., egg, larval) are required
as part of the verification process.
Photographs of juvenile reptile stages are not always required, but are strongly recommended.
Maryland Amphibian and Reptile Atlas Handbook - 26
When to record larval (“L”)
In Maryland, only amphibians will have a larval stage. This is characterized by the presence of
external gills in salamanders (with the exceptions of common mudpuppy, whose adults retain
external gills; and the gilled phase of some aquatic adult red-spotted newts). In the case of the
two exceptions, there are other diagnostic features to be used to distinguish larvae from adults.
Record salamanders as Larval (“L”) until the gills are absorbed and adult coloration and
patterning are present. Some salamanders do not have a larval stage (Table 2) and instead hatch
into miniature adults. These individuals should be recorded as Adult (“A”).
Table 2. Salamander species that do not have a larval
stage. These species hatch into mini-adults and are to
be recorded as either “A” (adult) or “E” (egg) when
observed.
Species
Eastern red-backed salamander (Plethodon cinereus)
Valley and ridge salamander (Plethodon hoffmani)
Northern slimy salamander (Plethodon glutinosus)
Wehrle’s salamander (Plethodon wehrlei)
Green salamander (Aneides aeneus)
Larval anurans / tadpoles are to be recorded as “L” until they take on the form of an adult.
Metamorphs / froglets with the body shape of an adult, whether or not they possess a tail, are to
be recorded as adults (“A”).
When to record juvenile (“J”)
Only reptiles may be reported as juvenile life stages. Most reptiles have hatchlings that have
different color patterns from adults of the same species. Hatchling turtles and juvenile skinks are
typically quite distinct from adults and recording life stage information with photographs is
particularly important for verifying the record.
No juvenile amphibians are to be recorded because it is difficult to distinguish this life stage
from the adult life stage in most species.
Maryland Amphibian and Reptile Atlas Handbook - 27
Where and How Do I Start?
After reading this handbook, you are probably ready and eager to get started!
First and foremost, it is important to become familiar with your quad. Familiarize yourself with
your quadrangle map and print additional maps as needed. The majority of quad maps have not
been updated since the 1970s and landscape features may have changed dramatically.
Additionally, many small wetlands such as seasonal pools and other natural features may not
show up on the quad map. You may also find an ADC Mapbook, other map sources, and aerial
photos very helpful. Atlasers are encouraged to keep a field notebook to record notes about
current and potential survey areas.
Keep in mind that the landscape and water features may look very
different seasonally, so remember to visit your quad early in the
season and often! Additionally, proper timing of visits is crucial!
How to Find Amphibians and Reptiles
Generally, amphibians and reptiles are most active from early spring through late fall. Close
attention must be paid to the timing of the year and environmental conditions to yield maximum
success. Calendars of Peak Activity for each herp order/suborder are provided in the appendix.
Although amphibians and reptiles can have different habitat preferences, the majority of herps
seek refuge under cover objects. Cover objects include those found naturally in the environment
(rocks, logs, bark and woody debris, vegetation, and leaf litter), as well as man-made objects
(most notably discarded items like plywood, sheet metal, tires, and other trash). Cover objects
can also be found in aquatic systems – rocks and vegetation are favorite hiding places for larval
amphibians. Eggs and egg masses may be found under a cover object, often accompanied by an
adult guarding the clutch, or attached to vegetation or floating in an aquatic habitat, as is the case
for many amphibians. When searching habitat, try to “think like a herp” – “does this habitat keep
me moist or dry and allow me to regulate my body temperature through basking and hiding?
Does it provide me with an abundant food source?”
As searches are conducted, please remember that herps and their habitat should be treated
with care and respect (See: atlasing ethics). Recommended field guides and reference
materials are provided in the appendix of this document for enhancing understanding of
herpetofauna and their habitat as well as providing identification instruction.
Maryland Amphibian and Reptile Atlas Handbook - 28
Maximizing success: Where and how to search
Amphibians
As discussed earlier, amphibians are dependent upon moisture for respiration and breeding and
are thereby closely associated with aquatic habitats. Breeding sites are very influential to
amphibian distribution. Some species are very specific, requiring seasonal pools free of fish for
optimal breeding, while others can utilize a broad range of breeding habitat.
All freshwater aquatic habitat types (described in Habitat classification system) should be
searched for amphibians. Maryland amphibians are not adapted to brackish or saltwater systems.
Amphibians may also be present in upland settings. Toads, as well as some salamanders, are not
as dependent on very wet conditions, and can derive the moisture needed from the moist soil
beneath cover objects. Some seasonal pool breeding amphibians, such as the wood frog and mole
salamanders (Ambystoma spp.), disperse to upland areas following breeding. Therefore, it is
important to search terrestrial habitats as well, taking care to actively flip logs, rocks, human
refuse, and other cover objects.
Remember, amphibians have soft skin that is very delicate. It is important to keep handling to a
minimum and use only moist hands free of soaps and chemicals when they must be handled for
positive identification. Furthermore, early life stages are very sensitive and vulnerable times for
developing amphibians. If necessary, handle larvae using dip nets and containers and avoid
contact with external gills. Eggs should not be handled unless it is absolutely necessary to obtain
a photograph. If that is the case, simply place hands gently under the eggs mass and keep
suspended in water. Return egg mass exactly as it was encountered. Furthermore, photographs of
egg masses may be captured without handling them; simply shade the mass with a clipboard or
other object before taking the picture.
Salamanders
All salamanders require a moist environment, but the type of preferred habitat varies among
species. Regardless of habitat type, salamanders tend to be secretive and seek refuge under cover
objects. This includes aquatic larvae that can often be found under rocks and amongst wet leaf
packs and submerged vegetation. In some cases, a larval salamander can be present in very
shallow areas that are just moist enough to wet their gills. For pool and pond breeders, larvae can
sometimes be seen swimming in open water. Some salamanders and newts can also be found
walking on the forest floor and wetland substrate and even crossing roads under certain
conditions.
Some methods for searching for salamanders are:
 Actively turn over logs, rocks, and other refugia. Some salamanders will remain
completely still; others may freeze then flee in a burst of energy, retreating to another
cover object or into the water.
 Use hands or a tool to rake leaf litter and mud. Concentrate in transition zones from wet
to dry, such as around the perimeter of streams and wetlands where the leaf litter is often
Maryland Amphibian and Reptile Atlas Handbook - 29



very wet. Seeps, springs, seasonal pools, and wetlands free of predatory fish are
particular hot spots for salamanders.
Move and look under vegetation, particularly mats of sphagnum moss, vegetation, or
skunk cabbage in wetlands.
Use a dip net in the seasonal pool, wetland, pond, lake, or stream. If surveying in
flowing water, place the net downstream of a cover object (usually rocks and leaf packs)
so that the animals hiding beneath it will wash into your net.
Look for clutches of eggs underneath rocks and logs (both in aquatic and upland
settings), rolled in vegetation or tucked in sphagnum moss, or attached to woody debris
and vegetation in seasonal pools.
There are a few species that require special survey techniques to increase the chance of detection.
For example:
 Eastern mud salamander – it is important to target certain wetland habitats and rake a
few inches of mud from the surface layer in an attempt to reveal a tunneled individual.
 Four-toed salamander – utilizes sphagnum moss in bogs, fens, and other wetlands for
nesting.
 Green salamander – has a very small known range in Maryland associated with rocky
outcrops, so try to target accordingly.
 Eastern hellbender and common mudpuppy – have very specific habitat niches;
further investigation will be needed to enhance survey methods.
Tips on timing:
 Salamanders are most active during very early spring and fall. Warm, soaking rains
during these seasons are particularly productive. However, more aquatic or streamside
salamanders may be observed year round.
 In general, salamanders tend to be more active at night, particularly under rainy or humid
conditions. Any habitats that can be searched during the day may likely be even more
productive at night.
 Survey during breeding migration periods to tremendously increase chances of
encountering a mole salamander (family Ambystomatidae) or other seasonal pool
breeder. Most species of mole salamanders migrate in the spring (typically mid-February
through late April), while marbled salamanders move to breeding areas in the late
summer or fall (generally starting around mid-September).
 These relatively large and conspicuous salamanders may even be observed crossing
the road or in pot holes or roadside tire ruts during their quest to find a mate.
 Once breeding is complete, these individuals will retreat to upland areas, making
them more difficult, but not impossible, to detect.
Maryland Amphibian and Reptile Atlas Handbook - 30
Frogs and Toads
Frogs and toads (collectively known as “anurans”) tend to be a bit more conspicuous than
salamanders. As a group, anurans are more mobile. Also, many are active diurnally (during the
day), and males will call in the spring and summer to advertise for a mate. However, just as with
salamanders, anurans rely heavily on varying degrees of moisture in the environment, and some
have very specific habitat preferences.
Some methods for searching for frogs and toads are:
 Listen carefully while searching habitat. Frog calls are generally very easy to
distinguish and learn. Some recommended frog call references are located in the
appendix.
 Walk slowly and carefully around the perimeter of wet areas. Many frogs will remain
at the side of a wetland, pond, or stream and retreat into the water at the first threat of
danger. Being aware of this behavior will increase the likelihood of spotting a fleeing
frog. If unable to get a good look initially, be patient. Focus on the movement of the frog
and where it settles in the water. Frogs will also frequently return to the same basking
spot that was occupied before being disturbed.
 Watch your step and keep an eye out ahead. Frogs and toads will often flee when
approached or disturbed. Watch for movement in vegetation, particularly tall grass, and
especially beneath your feet!
 Turn cover objects. Frogs and toads will often seek refuge in cool, moist areas in the
heat or will conserve energy under cover objects in cooler weather.
 Dip net for tadpoles. Tadpoles can often be seen basking near the surface of the water in
seasonal pools and wetlands. Take care to look at pools and other still areas in streams for
American bullfrog, northern green frog, and pickerel frog tadpoles. American and
Fowler’s toads, as well as eastern spadefoots, are explosive breeders and may not be as
rigid in the habitat they select for egg laying (e.g., tire ruts).
 Look for clutches of eggs floating as mats in bodies of water or attached to woody debris
and vegetation in seasonal pools.
 If searching at night, use a flashlight or headlamp to locate frogs by their eye shine.
Sometimes only the eyes are visible as they peek out from the water surface.
Tips on timing:
 Spring breeding season is a busy time – anurans will congregate at breeding areas
(typically seasonal pools and wetlands), engaging in risky, conspicuous behavior while
advertising for mates.
 Understanding breeding phenology (i.e., the timing of breeding) will aid in encounters of
many species, particularly hard-to-detect species like eastern spadefoot.
 Eastern spadefoot are primarily fossorial (living underground), often only emerging
in very heavy rain. They return to their reclusive lifestyle in a matter of days.
Maryland Amphibian and Reptile Atlas Handbook - 31
Reptiles
Reptiles as a group can be found in a much broader range of environments and habitats. Unlike
amphibians, reptiles do not breathe through their skin and do not need stay moist. On the
contrary, many will actually spend time basking to dry the skin, warm body temperatures, and
aid in digestion and uptake of nutrients.
Habitat preferences vary among and within the three major groups of reptiles in Maryland, so
consult the list of recommended field guides and reference materials for more information.
Turtles
Most turtles in Maryland can be found using both terrestrial and aquatic habitats. Generally, all
species can be found in and around wet areas. This section will discuss tips on how to search for
terrestrial and semi-aquatic turtles. A discussion on surveying for sea turtles (family
Cheloniidae) is provided later in the handbook.
Some methods for searching for turtles are:
 Walk the perimeter of lakes, ponds, wetlands, and stream banks.
 Sometimes basking or foraging turtles will be right on the water’s edge and can be
observed diving to escape. Many will be observed directly in the water.
 Spillways of millponds are a good place to look for aquatic turtles, especially mud
and musk turtles.
 Scan for basking turtles.
 A pair of binoculars or a spotting scope is particularly helpful for viewing turtles that
may be basking on emergent objects (such as logs and rocks) in the middle of a water
body.
 Turtles inhabiting bogs and other wetlands will often bask on tufts and mats of
vegetation. Sometimes individuals will bask on roads and bike/footpaths.
 Scan for surfacing aquatic turtles. While scanning the water surface for potential
basking sites, keep an eye out for the heads or carapaces of turtles surfacing as
individuals come up to breathe.
 Search vegetation.
 Concentrate on vegetation such as grasses and reeds around the perimeters of wet
areas. These are favorite hideouts and basking sites for hatchling turtles.
 Walking the edge of fields or searching dense vegetation within upland forests are a
good place to look for box turtles.
 Tread carefully! Many times turtles can be seen moving about on land. Unlike other
herps, turtles cannot move across land very quickly and will often freeze and remain still
until the threat of danger has passed. Be careful not to overlook them when walking or
surveying for other herpetofauna!
 Keep an eye out for shells and remains. Remains of turtles are often found, particularly
near roads and railroad tracks. As long as the shell is intact and in relatively good shape,
Maryland Amphibian and Reptile Atlas Handbook - 32
a positive identification can be made. Shells and other remains still represent the presence
of a species in the survey area.
Tips on timing:
 Turtles are most active during the day.
 Sunny days tend to be more productive than cloudy or rainy days for semi-aquatic turtles.
 Aquatic turtles are most often seen basking between 10 am and 3 pm, but will not leave
the water to bask (on logs, streambanks, vegetation, etc.) on days where the air
temperature is very hot (generally 90°F) or on especially cool days.
Snakes
Snakes can occupy nearly every type of habitat, from rock outcrops to streams and wetlands to
backyards and gardens. Snakes can be readily observed basking in the sunlight or under the
refuge of cover objects. Snakes are also quite mobile and can be seen moving about the
landscape or amongst the branches of bushes and trees. A large component of locating
individuals is considering if there are plenty of cover objects and ample food sources available.
Some methods for searching for snakes are:
 Actively turn over logs, rocks, and other refugia. Like other herps, snakes can often be
found tucked away in these microhabitats. Some species will also bury into sandy areas.
 Search both aquatic/floodplain and terrestrial/upland habitats and cover objects.
 Note that the use of a snake hook or similar tool is recommended in areas where
venomous snakes may be present.
 Search vegetation and in and around rock crops particularly in early spring and fall on
sunny days.
 Look up – particularly in trees and shrubs! Don’t just look at the ground or even
eye level. Some species of snake, such as northern rough greensnake, eastern ratsnake,
and northern black racer, may travel up quite a distance. Some aquatic snakes may also
be found up high from the water’s surface in woody debris jams.
 Move and rake away small piles of sticks and woody debris. These often overlooked
habitats can trap heat and provide just the right amount of humidity. They also make
good hiding places for prey items.
 Search in and around areas of human influence. Snakes will often try to occupy areas
where prey items like rodents or insects are plentiful.
 Areas with building materials and other artificial cover objects are particularly
enticing.
 Search old buildings with stone foundations, rafters of sheds and other semi-open
buildings, and abandoned properties.
 Walk the perimeter of lakes, ponds, wetlands, and stream banks. Snakes may be
observed basking or under a cover object/vegetation. Some snakes can be observed
foraging directly in the stream channel.
 Watch your step and keep an eye out ahead. Snakes may just be moving about or
fleeing as they are approached. Snakes may also find a foot path or road a suitable
Maryland Amphibian and Reptile Atlas Handbook - 33

basking site. Watch for movement in vegetation, particularly tall grass, and especially
beneath your feet!
 A cornered and otherwise threatened snake may also coil into a defensive posture and
strike, with or without the intent of actually biting.
Look for sheds and remains. Sometimes a positive ID can be made based on the shed
skin (and a little detective work). Unfortunately, there is a high occurrence of road
mortalities in snakes.
There are two species of special interest in Maryland:
 Rainbow snake – This species is listed as endangered in Maryland. It is highly aquatic
and secretive and is very difficult to detect. Feeding primarily on American eels, they
spend most of their lives hidden amongst aquatic vegetation and debris. Very rarely do
they bask, unlike other Maryland snakes. Historically, the earliest Maryland sighting is
June 13th and the latest is August 5th, and they have only been found on humid evenings
at sunset or later. However, in southeastern Virginia, they are known to be active almost
year round including diurnal activity.
 Northern pinesnake – There is some debate as to whether this species is native to
Maryland. It is considered native to New Jersey and Virginia and has been found in
Maryland and Delaware. It is extremely secretive and spends most of its time burrowed
underground in sandy, forested habitats. They may also occupy abandoned animal
burrows. This species can be quite cantankerous when threatened, hissing loudly,
vibrating its tail, and striking.
Tips on timing:
 Generally, snakes are most active from March/April to mid-June and again in late
August/early September.
 The majority can be found during the day basking or beneath cover objects, but some,
such as the copperhead, may forage at night.
 During hot summer months, snakes can be found at night warming themselves on rural
road sides.
 Like turtles, snakes hibernate from late fall through early spring. Hibernacula areas
should not be disturbed.
Lizards
Like snakes, lizards occupy a variety of habitats and may find backyard and garden habitats
acceptable. Overall, lizards tend to be found in dry, terrestrial habitats, although most skinks will
be in the vicinity of streams.
Some methods for searching for lizards are:
 Actively turn over logs, rocks, and other refugia. Logs, loose bark, rocks, old trash,
boards – any debris – may offer a good hiding place for lizards and their invertebrate
prey. As with snakes, areas with building materials and other artificial cover objects are
particularly inviting.
Maryland Amphibian and Reptile Atlas Handbook - 34




Scan for basking lizards. Some favorite basking sites are rocky outcrops, logs, trees,
fences, and old building materials. Exposed rocky areas in forested regions and open
rocky spots in the vicinity of streams may be particularly productive.
Be sneaky. Maryland lizards are streamlined and quick. It does not take much to startle
them and send them darting under a cover object or running up a tree. But, a lizard might
remain basking as a stealthy observer creeps over to snap a picture.
 It is very important to get close enough to photograph the scales on the head of skinks
for positive identification (See: Photodocumentation).
Watch your step and keep an eye out ahead in order to catch a fleeing lizard. In some
cases, a lizard will dart right across your path.
Look up! Don’t just look at the ground or even eye level. Some lizards, such as the
eastern fence lizard and broad-headed skink, are excellent climbers and may more often
be encountered off the ground.
Tips on timing:
 Generally, lizards in Maryland tend to be active anytime from early April to late
September.
 They are diurnal and most often observed basking in the sun or hiding beneath cover
objects.
 Warm, sunny days tend to be the most productive.
Road cruising
Roads can be a good place to find herps – unfortunately, they are frequently found as mortalities.
Roadways have a tendency to bisect habitats and wildlife corridors, and herpetofauna are often
struck as they move across roads on the way to suitable breeding and nesting sites. In addition to
breeding season mortalities, herps are also hit while searching for wet areas during dry months or
while attempting to bask on the warm asphalt. Some may even breed or place a nest in a roadside
ditch. Remember that road-killed animals still represent the presence of the species and can
provide valuable data.
Keep this in mind while surveying and consider the following:
 Spring is the most productive season for road cruising as amphibians migrate to
breeding sites.
 Drive slowly along back roads and little-used highways after dark.
 Concentrate on areas where roads border or bisect wetlands and breeding habitats.
This will be particularly successful at night during wet conditions – especially after or
during a warm, soaking springtime rain event.
 Stop periodically to listen for choruses of anurans or calling individuals.
 Look carefully at wet tire ruts and potholes which may provide a temporary refuge for
amphibians.
Road cruising can be a part of your survey efforts as you navigate to the site or drive in search of
certain habitats. Record the time you spend road cruising for herps.
Maryland Amphibian and Reptile Atlas Handbook - 35
Always look for road-killed animals or those trying to cross the road, even when not actively
surveying. Incidental encounters are useful data. Just be sure to note your location (county, quad,
and block or lat/long coordinates) and record your findings as soon as possible so not to forget.
If moving a herp off of the road, help it to cross in the direction it was heading. Only stop to
assist a herp or observe live or dead individuals when it is safe to do so!
Surveying for sea turtles
The most effective way to survey for sea turtles is to be out on the open water. This can be
achieved by involving and promoting awareness among various groups (e.g., commercial and
recreational fisherman through the Maryland State Waterman’s Association) that spend
considerable time in the Chesapeake Bay, as well as by posting fliers at marinas and boat ramps.
The National Oceanic and Atmospheric Administration (NOAA) Southeast Fisheries Science
Center (SEFSC) and the Maryland Department of Natural Resources (MDNR) maintain a sea
turtle stranding and salvage network (STSSN). This network solicits stranding reports for any
live or dead sea turtle found at sea or washed up on shore.
The STSSN report form and detailed instructions are included at the end of the appendix.
Should you encounter a stranded or dead sea turtle, please immediately contact:
Sea Turtle & Marine Mammal Stranding Biologist
Maryland Department of Natural Resources
Cooperative Oxford Laboratory
904 South Morris Street
Oxford, MD 21654-1324
**Stranding Cell Phone: 443-758-6607**
Office Phone: 410-226-5193 ext 132
Fax: 410-226-0120
Once the above contact has been made, the STSSN report form can be completed paying
particular attention to the following items:
1) Location
2) Species identification or documentation of color, length, head shape, and carapace shape
3) Carcass condition; e.g., alive, fresh dead, moderate decomposition, advanced decomposition,
skeleton
4) Obvious signs of human interaction; e.g., entangled in gear or plastic, propeller wounds, etc.
5) Surrounding environment; e.g., fishing nets in area
Maryland Amphibian and Reptile Atlas Handbook - 36
Verification Procedures
Verification of all amphibian and reptile species is encouraged for all species and required for
some (those denoted with an asterisk on the data sheet). Verification of early life stages (eggs,
larval amphibians, hatchling turtles, juvenile skinks) in the form of a photograph or vouchered
specimen is necessary to confirm species identification.
Photodocumentation
In most cases, the simplest means to verify a species will be by photograph. For certain species a
single photograph will suffice, while others will require additional photographs of specific
features. Note that herps can often be recovered after escape attempts, so fixate on the animal; if
it flees, watch where it goes.
Some general tips for photographing herpetofauna are:
 It is always beneficial to include a size reference (such as a coin) as part of the photo
voucher.
 Utilize the camera’s macro or super macro functions when taking close up pictures,
specifically when capturing features such as head scales, iris pigmentation, or small
markings on the head.
o The macro setting is generally represented by flower/tulip symbol and can often be
turned on and off similar to the flash setting.
 An umbrella, or other method of shading, can be utilized to remove the glare on egg
masses and other wet surfaces.
 Try to minimize stress to the animal to the greatest extent practicable.
 Capture photographs of the animal in the field and in the position they are found
whenever possible.
 Move slowly and methodically and exercise patience to capture the necessary shots.
 Digital photos are preferred for MARA.
 All photos should be labeled with the quad, block, date, species code
(listed in the appendix), sequential photo number, observer name
(including initials), and lat-long (optional). For example:
PriceNW_2010Apr22_FOTO_01_GDTherres_N35-0000W76-0000
The following represent some of the species or groups of species and the specific photographs
that are helpful or required for identification to species:
Salamanders
Generally, different features need to be captured for different life stages, and key features are
needed for specific species. Patterning and body shape are important diagnostic criteria for adult
salamanders. Larval salamanders should be photographed in the water to best capture gill
structure. Containers or plastic bags can facilitate taking photos of necessary features.
Maryland Amphibian and Reptile Atlas Handbook - 37
1. Larva – Whole body (dorsal & lateral views), head, gills, legs, tail. Gill structure and
head shape most important features (Figure 7). Pigment of throat for some species.
2. Adult – Body profile, dorsum, venter. Side of head and face on.
Taxa-specific (diagnostic features that must be captured):
1. Desmognathus spp. (northern dusky salamander, Allegheny mountain dusky salamander,
seal salamander) – side of head (Figure 8); body profile (capturing size of legs and body
patterning).
2. Northern spring salamander – Profile and head on shot of face (Figure 9).
3. Northern red salamander versus Eastern mud salamander – dorsal patterning and
coloration, side of body, eyes (need to be able to distinguish iris pigmentation).
4. Wehrle’s and Valley and ridge salamanders – dorsum, venter, and chin pigmentation
and patterning.
5. Ambystoma spp. larvae – gills, tail fin/membrane, dorsum, pigment on throat.
Without gill rachises, branching from the base and
appearing shrub / antler-like (Desmognathus sp.)
Gills with rachises (comb-like structures) and
fimbriae (all other species w/aquatic larvae)
Figure 7. Gill structure of Maryland salamanders with aquatic larval stage.
“Desmog line” – Pale diagonal line
extending from eye to the angle of jaw
Rear legs conspicuously
larger than front limbs
Figure 8. Key features of salamanders in the genus Desmognathus to be photographed.
Figure 9. Diagnostic feature of northern spring salamander
(Gyrinophilus porphyrticus porphyriticus)
Canthus rostralis – light line
bordered by gray or black
extending from eye to nostril;
snout squarish
Maryland Amphibian and Reptile Atlas Handbook - 38
Frogs and Toads
Body shape separates families of anurans. Coloration, dorsal patterning, and key features are
needed when identifying to species. Containers or plastic bags can facilitate taking photos of
necessary features in larvae.
1. Adult Frogs – Whole body in profile (Figure 10A). Dorsum (shot from above so that
dorsolateral ridges can be distinguished; Figure 10B). Venter, specifically inside of rear
legs.
2. Adult Toads – Dorsum (including top of head and back), parotoid glands, tibial warts,
and chest. Make sure number of warts per dorsal spot can be distinguished in picture.
When possible, try to use a macro setting and photograph the cranial crest in relation to
the parotoid gland (Figure 10C).
3. Larval Frogs and Toads (tadpoles) – Profile is most important, followed by venter
(including mouth parts) and dorsum.
A. Profile shot. Should capture
patterning and distinct markings
on back, side, and tympanum
(eardrum)
B. Dorsal shot of frog.
Dorsolateral ridges and
patterning should be easily
distinguishable.
C. Dorsal shot of toad. Needs
to capture number of warts per
dark spot and placement of
cranial crest in relation to
paratoid glands. Additional close
ups may be needed on parotoid
glands and tibial warts.
Figure 10. Features to capture during photodocumentation of frogs and toads.
Family- and species-specific (diagnostic features that must be captured):
1. Chorus frogs – dorsal markings, profile.
2. True frogs (Lithobatidae) – dorsal markings, presence and degree of dorsolateral ridge.
3. Pickerel vs. leopard frogs – Profile. Must clearly see tympanum (eardrum). Dorsal
markings.
Turtles
Different species of turtles are typically separated by overall body and shell shapes, as well as
patterning on the head.
1. Adults of all species (with the exception of sea turtles): head (side and top), carapace,
and plastron.
Maryland Amphibian and Reptile Atlas Handbook - 39
2. Juveniles and hatchlings – photograph all features and use size reference (ruler or coin
preferred).
3. Sea Turtles – Head and carapace (dorsal shell) on living turtles; plastron (ventral shell) if
found washed up on the beach. Do not try to handle or disturb a live sea turtle (See:
Surveying for sea turtles for what to do when a stranded sea turtle is encountered).
Species-specific (diagnostic features that must be captured):
1. Bog turtle vs. Spotted turtle– orange patch on side of head; carapace.
2. Eastern mud turtle vs. Stinkpot – Plastron (hinges and amount of plastron covering
appendages). Lines/patterning on head, barbels on chin and throat of stinkpot.
3. Northern red-bellied turtle vs. Painted turtle vs. Red-eared slider – profile of head
and head-on to capture cusps of jaw.
Snakes
Patterning on the top, side, and venter of snakes as well as head and body shape are important for
differentiating species. Juvenile ratsnakes, racers, and watersnakes are often mistaken for other
species.
1. All Snakes (adults and juveniles) – Capture body shape and pattern (dorsal and ventral);
Side and top of head, and underside of anal opening/tail.
Species-specific (diagnostic features that must be captured):
1. Eastern ratsnake vs. northern black racer (adult and juvenile) – Body shape, venter
and dorsal coloration and pattern, side of head and top of head.
2. Northern watersnake – dorsal and ventral coloration / patterning.
3. Red cornsnake – top of head and post-ocular stripe (Figure 11).
4. Eastern milksnake – body patterning and color, dorsal blotch on the nape of the neck
(Y, U, or V shape).
5. Eastern wormsnake, Eastern smooth earthsnake, northern brownsnake – tip of tail
(eastern wormsnake ends in a sharp spine), head shape, size, and coloration; dorsal and
ventral coloration.
6. Northern red-bellied snake – top of head (with nape of neck), side of head (pre-ocular
and labial scales).
7. Northern scarlet snake – dorsal patterning, black band across head behind eyes, side of
head to show snout projection.
Top of head
Post ocular stripe
Figure 11. Key features of red cornsnake (Pantherophis guttatus) to be photographed.
Maryland Amphibian and Reptile Atlas Handbook - 40
Lizards
Take a photograph of the whole body and any ventral patterning. A profile shot of BOTH
SIDES of the head is particularly important in skinks (family Scincidae).
Species-specific (diagnostic features that must be captured):
1. Common five-lined skink vs. broad-headed skink – Both sides of head, especially the
upper lips, (Figure 12). Distinguishing features are provided in Table 3.
2. Juvenile / “Blue-tailed” skinks – same features as common five-lined and broad-headed
skinks above.
a. Note that juvenile six-lined racerunners also have blue tails. A picture of the
entire body as well as the head will allow this species to be easily distinguished
from juvenile skinks.
Figure 12. Scales that must be captured in photograph to distinguish
common five-lined skink (Plestiodon fasciatus ) from broad-headed skink
(Plestiodon laticeps).
A – Preorbital Supralabials
B - Postlabial
Table 3. Distinguishing features between common five-lined skink and broad-headed skink.
Species
Common five-lined skink
(P. fasciatus)
Broad-headed skink
(P. laticeps)
Preorbital
Supralabrial
Count
Postlabial
condition
Longitudinal scale row
count at Midbody*
4
2 Enlarged
26-30
5
Not enlarged /
modified
30-32
*Conant and Collins, 1998.
Maryland Amphibian and Reptile Atlas Handbook - 41
Audio recording and sonogram preparation
As noted under the section on Filling Out the Data Sheet, documentation of the presence of
certain frog species can be obtained by listening for the calls of advertising males. Species
verification for calling frogs can be accomplished by collecting audio recordings of a breeding
chorus or individual frogs. The time and temperature in the field must be captured at the time the
recording is made.
 When you submit a tape or digital sound file as species verification, please
note the date, location, and temperature at the time of the recording.
 Verification codes (provided in the appendix) should be used when
submitting audio recordings for documentation.
An audio recording is mandatory to distinguish the two gray treefrog species, as they can only
be separated in the field by differences in call rates. Temperature is particularly important to
capture, as colder temperatures can slow the call rates sufficiently to make separation
problematic. Reliable separation between the calls of H. versicolor and H. chrysoselis should be
done when ambient temperatures are above 24°C (75°F).
County coordinators will utilize software to distinguish the calls. Instructions for analyzing
recorded frog calls are found in the appendix.
Maryland Amphibian and Reptile Atlas Handbook - 42
References
The following publications were used in the preparation of this handbook:
Conant, Roger, and Joseph Collins. 1998. A Field Guide to Reptiles and Amphibians of Eastern and Central North
America. 3rd Edition. Peterson Field Guide Series. Houghton Mifflin. 616 pp.
Cooper, J. E. 1960. Distributional Survey V of Maryland and the District of Columbia. Bulletin of the Philadelphia
Herpetological Society May-June:18-24.
Crother, B. I., 2008. Scientific and standard English names of amphibians and reptiles of North America north of
Mexico, with comments regarding confidence in our understanding. Sixth edition. Society for the Study of
Amphibians and Reptiles, Herpetological Circular. 92 pp.
Harris, H. S. 1969. Distributional Survey: Maryland and the District of Columbia. Bulletin of the Maryland
Herpetological Society 5(4): 97-161.
Harris, H. S. 1975. Distributional Survey (Amphibia/Reptilia): Maryland and the District of Columbia. Bulletin
Maryland Herpetological Society 11(3): 73-167.
Hulse, A. C., C. J. McCoy, and E. Censky. 2001. Amphibians and Reptiles of Pennsylvania and the Northeast. New
York: Comstock Publishing Associates. 419 pp.
McHugh, M. and L. J. Niles. 2002. New Jersey’s herp atlas project: herp atlas volunteer training manual. New
Jersey department of environmental protection division of fish and wildlife endangered and nongame
species program. Available online at <www.state.nj.us/dep/fgw/ensp/pdf/herpatlas_train_manual05.pdf>
Stranko, S., S. Smith, L. Erb, and D. Limpert. 2007. A Key to the Reptiles and Amphibians of Maryland. Maryland
Department of Natural Resources, ChesapeakeBay and Watershed Programs, Monitoring and Non tidal
Assessment Division.
Zweifel, Richard G. 1970. Distribution and mating call of the treefrog, Hyla chrysoscelis, at the northeastern edge of
its range. Chesapeake Science 11(2): 94-97.
Acknowledgements
We are particularly grateful to the three MARA Co-Chairs – Glenn Therres (Maryland
Department of Natural Resources), Charles Davis (Natural History Society of Maryland), and
Christopher Swarth (Jug Bay Wetlands Sanctuary) – for their dedication to the 2009 pilot study
and overall atlas effort.
We thank the Maryland Amphibian and Reptile Atlas steering committee for guidance in the
preparation and review of this document. Thank you to Glenn Therres, Nate Nazdrowicz, Wayne
Hildebrand, David Walbeck, Lynn Davidson, Christopher Swarth, and Scott A. Smith for their
careful review and invaluable contributions to the document. Special acknowledgement goes to
Wayne Hildebrand for compilation of the county species lists and frog peak activity calendar and
to Christopher Swarth, Scott Smith, and Rachel Gauza for preparation of the turtle, snake, lizard,
and salamander peak activity calendars, respectively. We are grateful to Lynn Davidson for her
dedicated work on the database and thorough data submission procedures. Thank you to Scott
Maryland Amphibian and Reptile Atlas Handbook - 43
Smith for his extensive reference and resource list, Kyle Rambo for providing sea turtle
surveying techniques, and Lance Benedict for information provided on the natural history of
rainbow snake in Maryland. Finally, we would like to highlight Jennifer St. John’s talents in
production of the MARA logo.
Illustrations in the handbook are adopted from David Kazyak in Stranko et al. (2007). General
formatting from McHugh and Niles (2002); glossary from McHugh and Niles (2002) and Hulse
et al. (2001).
Funding for the Maryland Reptile and Amphibian Atlas project is being provided, in part, by
State Wildlife Grant funds provided to the state wildlife agencies by US Congress and
administered through the Maryland Department of Natural Resources’ Wildlife and Heritage
Service.
Steering Committee Members and Affiliations
(As of January 2010)
Member
Affiliation
Glenn Therres *
Maryland Department of Natural Resources
Charles Davis *
Natural History Society of Maryland
Christopher Swarth *
Jug Bay Wetlands Sanctuary
Scott A. Smith
Maryland Department of Natural Resources
David Smith
Coastal Resources, Inc.
Rachel Gauza
Montgomery County Department of Environmental Protection
David Walbeck
Maryland Department of the Environment
Wayne Hildebrand
North American Amphibian Monitoring Program
Lynn Davidson
Maryland Department of Natural Resources
Linda Weir
United States Geological Survey, Patuxent Wildlife Research Center
Kyle Rambo
Patuxent Naval Air Station, Environmental Department
Nate Nazdrowicz
University of Delaware
Jim White
Delaware Nature Society
Don Forester
Towson University
Joel Snodgrass
Towson University
Matt Evans
Smithsonian Institution, National Zoological Park
Lance Benedict
Chuck Saunders
* - Co-Chair
Maryland Amphibian and Reptile Atlas Handbook - 44
Glossary
Anal plate: scale (single or divided) that is just anterior to the vent (cloaca) of a snake and some lizards.
It marks the beginning of the tail.
Anterior: towards the head or front.
Aquatic: organism that lives in the water.
Arboreal: organism that prefers to climb in vegetation such as trees, shrubs and vines.
Band: a marking that encircles the body, is perpendicular to the length of the body.
Bar: a roughly rectangular marking, generally runs across the body.
Barbels: small fleshy projections, usually located on the chin or throat of an animal.
Canthus rostralis: a ridge that runs along the side of the head from the corner of the eye to the nares
that is lighter in color than the rest of the head.
Carapace: upper part of a turtle shell.
Caudal autotomy: the ability of an animal to shed its tail; common to many species of salamanders and
lizards.
Cloaca: the chamber or cavity just inside the vent at the end of the digestive tract where the intestinal,
genital, and urinary tracts open. It opens to the exterior through the anus.
Costal groove: thin vertical groove on side of salamander’s body in the area between the front legs and
back legs.
Cranial crest: bony ridge located on the head of most toads.
Diurnal: active during the day.
Dorsal: referring to the back. (“Dorsum” refers to the entire upper surface of an animal.)
Dorsolateral: a region on the back, but more towards the sides than the middle of the back.
Dorsolateral ridges: fold of raised skin along each side of the bank in some frogs.
Fimbriae: hair-like extensions on the surfaces of gills that facilitate gas exchange.
Flagellum: narrow projection at the terminal end of the tail in some tadpoles that is capable of moving
independently from the rest of the tail.
Flank: side of the body, running from the front legs to the hind legs.
Fossorial: referring to an underground existence or underground activity. Adapted for digging or
burrowing and usually living underground.
Gill slit: an external opening at the side of the neck through which water flows out of the gill chamber.
Ground color: more of the body is this color than any other color. Patterns are superimposed on this
background color.
Gular: on or pertaining to the throat.
Hemipenes: the copulatory organs of males. Snakes and lizards have two hemipenes and turtles have
one hemipinis.
Maryland Amphibian and Reptile Atlas Handbook - 45
Hibernation: a state of inactivity brought about by reduced environmental temperatures.
Hybrid: offspring of a cross between two different species.
Intergrade: referring to the organism resulting from a cross between members of different subspecies or
species.
Iris: colored portion of the eye.
Iridophores: cells that contain light pigments and produce brassy, silvery, golden, or whitish coloration on
the body.
Keeled scale: scale with protruding, lengthwise ridge.
Keeled tail: tail with a narrow, knife-edge on top.
Labial: referring to the lips, as in labial scales.
Larva / Larval: the gilled immature stage of frogs, toads, and some salamanders.
Lateral: referring to the side.
Lentic: standing water (i.e., lakes, ponds, bogs, swamps, wetlands).
Leucistism: reduced pigmentation in all pigment, not just melanin (as in albinism). An individual with this
physical characteristic / phenotype would be called “Leucistic.”
Longitudinal: a marking that runs in the same direction as a line would run from the head to the tail
Loreal pit: A depression between the eye and the nares (in the loreal scale) of rattlesnakes and
copperheads that contains heat-sensitive receptors.
Lotic: running / flowing water (i.e., springs, streams, rivers).
Medial: pertaining to the middle of the body or toward the middle.
Melanism: an increased amount of dark pigmentation resulting from the presence of melanin. Individuals
displaying this trait are known as “Melanistic” and may appear black in coloration, which may obscure any
pattern that would otherwise be apparent.
Melanophore: cells that contain dark pigment / melanin.
Metamorph: young immature adult amphibians that have recently transformed from the larval stage.
Metamorphosis: a series of changes that occur when a larva transforms to an adult.
Middorsal: along the middle / center of the back.
Midline: an imaginary line running lengthwise down the middle of the body.
Mole salamander: salamanders in the family Ambystomatidae. Members of this body are stout-bodied
with short, round heads and conspicuous costal grooves. Mole salamanders in Maryland are obligate
species of seasonal pools, meaning these habitats are critical for optimal reproductive success.
Nasolabial groove: thin line that runs down from nostril to lip in some salamander species.
Neonate: a recently born or hatched individual.
Niche: the functional role of an organism in its ecological community, including activities and relationships
with both living and non-living components.
Nocturnal: active mostly at night.
Maryland Amphibian and Reptile Atlas Handbook - 46
Parotoid gland: gland found on the shoulder, neck or behind the eye of toads; the gland usually forms a
large swelling.
Phenology: the study of periodic plant and animal life cycle events and the relationship to weather and
climate.
Plastron: bottom part of a turtle shell.
Posterior: towards the rear.
Post ocular: behind the eye.
Postlabial scales: the scales immediately in front of the ear openings and in line with the upper labial
(lip) scales in lizards.
Rachis: the central portion of a gill that supports the gill fimbriae.
Reticulation: a net-like pattern, sometimes like a pattern of interwoven circles.
Ring: a marking that encircles the body.
Scute: horny plate that forms a distinct segment of a turtle shell.
Speckles: very small spots or flecks.
Spiracle: the external / excurrent opening for exit of water from the gill chamber in tadpoles.
Stripe: a marking that runs lengthwise along the body; may run part or all of the length of the body.
Subcaudal scales: the scales that form the ventral surface of (beneath) the tail of a snake.
Subocular scale: scales located below the eye.
Supralabial scale: any scale bordering the lateral margins of the upper lip of snakes and lizards.
Tympanum: eardrum. It is external and often conspicuous in many frog species.
Terrestrial: organism that mostly lives on land, not in the water.
Vent: excretory opening at base of belly; the cloacal opening.
Ventral: Underside / belly.
Maryland Amphibian and Reptile Atlas Handbook - 47
Suggested Reference Materials
Field Guides:
Behler, John L., and F. Wayne King. 1979. The Audubon Society Field Guide to North American Reptiles
and Amphibians. Knopf. 718 pp. This is a photographic field guide approach.
Conant, Roger, and Joseph Collins. 1998. A Field Guide to Reptiles and Amphibians of Eastern and
Central North America. 3rd Edition. Peterson Field Guide Series. Houghton Mifflin. 616 pp.
Gibbs, J.P., A.R. Breisch, P.K. Ducey, G. Johnson, J.L. Behler, and R.C. Bothner. 2007. The
amphibians and reptiles of New York state, identification, natural history, and conservation.
Oxford Univ. Press, NewYork, NY, 422 pp.
Green, N. B. and T. K. Pauley. 1987. Amphibians and Reptiles in West Virginia. Univ. of Pittsburgh
Press, Pittsburgh, 241 pp.
Hulse, A.C., C.J. McCoy, and E.J. Censky. 2001. Amphibians and reptiles of Pennsylvania and the
northeast. Cornell Univ. Press, Ithaca, NY. 419 pp.
Martof et al. 1980. Amphibians and Reptiles of the Carolinas and Virginia. The University of North
Carolina Press, Chapel Hill, 264 pp.
Mitchell, J. C. 1994. The reptiles of Virginia. Smithsonian Inst. Press, Washington, 352 pp.
Schwartz, V., and D.M. Golden. 2002. Field guide to reptiles and amphibians of New Jersey. NJ Div.
Fish. Wildl., Vineland, NJ., 85 pp.
Shaffer, L. L. 1991. Pennsylvania Amphibians and Reptiles. Pennsylvania Fish Commission, 161 pp.
Tyning, Thomas F. 1991. A Guide to Amphibians and Reptiles. Little, Brown and Co. 400 pp. Part of the
Stokes Nature Guide Series, includes detailed life history information.
White, James F and Amy W. White. 2007. Amphibians and Reptiles of Delmarva. 2nd Edition. Cornell
Maritime Press, Inc. 296pp.
Other Reference Books:
Altig, R. 1970. A key to the tadpoles of the continental United States and Canada. Herpetologica
26(2):180-207.
Behler, J. L. and F. W. King. 1979. The Audubon Society field guide to North American reptiles and
amphibians. Alfred A. Knopf, Inc., NY, NY, 743 pp.
Bishop, Sherman C. 1994. Handbook of Salamanders. Comstock Publishing Co., Cornell University
Press, Ithaca, NY. 555 pp.
Brown, LJ and R. E. Jung. 2005. An introduction to Mid-Atlantic Seasonal Pools. EPA/903/B-05/001. US
Environmental Protection Agency, Mid-Atlantic Integrated Assessment, Ft. Meade, Maryland
Carr, Archie. 1995. Handbook of Turtles: The Turtles of the United States, Canada, and Baja California.
Cornell University Press, Ithaca, NY. 542 pp.
Maryland Amphibian and Reptile Atlas Handbook - 48
DeGraaf, R. M. and D. D. Rudis. 1981. Forest habitat for reptiles and amphibians. USDA Forest Serv.
Techn. Rep., 239 pp.
Dickerson, M. C. 1969. The frog book, North American toads and frogs. Dover Publ., Inc. NY, NY, 253
pp.
Elliott, L., C. Gerhardt, and C. Davidson. 2009. The frogs and toads of North America, a comprehensive
guide to their identification, behavior, and calls. Houghton Mifflin Harcourt, New York, NY., 343
pp + CD.
Ernst, C.H. and E.M. Ernst. 2003. Snakes of the United States and Canada. Smithsonian Inst. Press,
Washington, D.C. 668 pp.
Ernst, C. H. and J. E. Lovich. 2009. Turtles of the United States and Canada. 2nd Ed., Johns Hopkins
Univ. Press, Baltimore, 827 pp.
Harris, H. S., Jr. 1975. Distributional survey (Amphibia/Reptilia): Maryland and the District of Columbia.
Bulletin of the MD Herpetological Society 11(3):73-170.
Heyer, W. R., M. A. Donnelly, R. W. McDiarmid, L. C. Hayek and M. S. Foster. Measuring and monitoring
biological diversity, standard methods for amphibians. Smithsonian Inst. Press, Washington, 364
pp.
Hulse,. AC, CJ McCoy, and E. Censky. 2001. Amphibians and Reptiles of Pennsylvania and the
Northeast. Ithaca, NY: Cornell University Press. 419 pp.
Kelly, H. A., A. W. Davis and H. C. Robertson. 1936. Snakes of Maryland. Nat. Hist. Soc. Md. 103 pp.
Lannoo, M. 2005. Amphibian declines, the conservation status of United States species. Univ. Calif.
Press, Los Angeles, CA. 1094 pp.
Mansueti, R. 1941. A descriptive catalogue of the amphibians and reptiles in and around Baltimore City,
Maryland, within a radius of twenty miles. Proc. Nat. Hist. Soc. Md. No. 7, 53 pp.
McCauley, R. H. 1945. The reptiles and amphibians of Maryland and the District of Columbia. Private
printing, Hagerstown, Md., 194 pp.
McClellan, W. H., R. Mansueti and F. Groves. 1943. The lizards of central and southern Maryland. Proc.
Nat. Hist. Soc. Md. No. 8, 42 pp.
Mitchell,. JC, AR Breisch, and K. A. Buhlmann. 2006. Habitat Management Guidelines for Amphibians
and Reptiles of the Northeastern United States. Partners in Amphibian and Reptile Conservation,
Technical Publication HMG-3, Montgomery Alabama. 108 pp.
Petranka, James W. 1998. Salamanders of the United States and Canada. Smithsonian University Press,
Washington, D.C. 587 pp
Scott, N. J. 1982. Herpetological communities. USDA Fish & Wildl. Serv., Wildl. Res. Rep. 13, 239 pp.
Schwartz, F. J. 1967. Maryland turtles. Univ. Md. Nat. Res. Inst., Educ. Ser. No. 79, 38 pp.
Smith, H. M. 1946. Handbook of lizards of the United States and Canada. Comstock Publishing Assoc.,
Ithaca, NY, 557 pp.
Maryland Amphibian and Reptile Atlas Handbook - 49
Szaro, R. C., K. E. Severson and D. R. Patton. 1988. Management of amphibians, reptiles, and small
mammals in North America. USDA Forest Serv. Gen. Techn. Rep. RM-166, 458 pp.
Tyning, T. F. 1990. Stokes Nature Guides series, A guide to amphibians and reptiles. Little, Brown and
Company, Boston, 400 pp.
Wright, Albert Hazen, and Anna Allen Wright. 1995. Handbook of Frogs and Toads of the United States
and Canada. Comstock Publishing Co., Cornell University Press, Ithaca, NY. 640 pp.
Wright, Albert Hazen,and Anna Allen Wright. 1957. Handbook of Snakes of the United States and
Canada. Vol I. and Vol. II. Comstock Publishing Co., Cornell University Press, Ithaca, NY. 1105
pp
Recordings:
Elliot, Lang, 1992. The Calls of Frogs and Toads. Nature Sounds Studio, Inc.
http://www.pwrc.usgs.gov/frogquiz/ (requires RealOne player; features frog call lookup & quiz)
http://www.nwf.org/frogwatchUSA/frogs_state.cfm (go to MD – shows list of 19 species w/spp. accounts,
images, descriptions of calls, and sound clips)
http://www.montgomerycountymd.gov/content/dep/herps/frogs.asp
http://www.wlf.state.la.us/experience/lawildlife/reptileandamphibian/LAMP/calls
http://animaldiversity.ummz.umich.edu/site/topics/frogCalls.html
http://www.naturenorth.com/spring/sound/shfr2snd.html (Additional plug-in may be required)
http://www.naturesound.com/frogs/frogs.html (requires Real Player)
http://allaboutfrogs.org/weird/general/songs.html
Internet Resources:
Altig Ronald, RW McDiarmid, K. A. Nichols, P. C. Ustach. Tadpoles of the United States and Canada: A
Tutorial and Key. Available online: http://www.pwrc.usgs.gov/tadpole/
Montgomery County DEP Amphibians and Reptiles Web Page:
http://www.montgomerycountymd.gov/deptmpl.asp?url=/content/dep/herps/list.asp
Towson University Herpetology: http://wwwnew.towson.edu/herpetology/Amphibians.htm
Maryland Amphibian and Reptile Atlas Handbook - 50