Transect Procedure
1. Spend some initial time surveying the study site, looking for obvious bands of zonation and
selecting the general area for your first transect.
2. As a team, decide on about twelve "key species'' of plants and animals to census. Not all organisms will
be present in every zone - some will be specialists found only in the Splash zone, but will be there in obvious
abundance - some will be present in all zones, such as small scavengers.
a. Make sure you include at least one marine plant in each of the zones - they represent food
available for grazers.
3. Make your selections based on the range of distribution of each species within the intertidal, its abundance,
and ease of identification.
a. Remember that many of these animals are small, often camouflaged, and may be hiding. Get down
on your hands and knees for a closer look.
b. Be sure to examine the undersides of rocks (please replace them in their original position), ledges,
and even blades of algae when choosing which species are most dominant along your WHOLE selected
transect line.
3. Use your field guides and test each other to make sure that everyone on the team can identify these organisms
with equal accuracy.
4. Extending your tape measure (or rope) perpendicular to shore, begin at splash zone and extending
outwards towards the ocean for 100 m.
5. You will need to sample TEN quadrat areas along the transect line. Secure your tape at either end. Based
upon the length of the section, the interval to the next quadrate can be either:
a) standardized, for seasonal or yearly comparisons - divide the transect length by ten and place
quadrats evenly along the line OR
b) randomly placed, using a random number table to measure off how many inches from the edge of the
latest quadrat the NEXT quadrat should be placed along the line... OR
c) randomly placed, by throwing a small rock over your shoulder to establish where along the line you will
begin your next transect square. Wherever it lands, place the beginning of your next quadrat in the same
relative place along the transect.
5. Identify and count the individuals of each key species within the quadrat.
a)If the number of individuals of a species is too large for convenient counting (over 100), put "100+"). Mark
data in data table #1.
6. Continue down towards the ocean until you have 10 quadrats from one transect.
7. Collect as much information as you can relating to such factors as may be helpful in understanding the role of the
plant or animal in the intertidal community inc luding:
a) substrate (silt, small rocks, algae-covered boulders, etc.),
b)food preferences
c)feeding behavior
d) associations with other plants and animals,
Intertidal Lab Report criteria
Before entering the habitat, each pair of students will identify a question about the rocky
shore which they want to answer.
In order to develop a sound question they must first understand what data can be collected and
what will be collected . They must ensure that their question can be answered through this field study.
You will want to think about connections between the abiotic factors in the habitat and particular
species or adaptations (both plants and animals) when developing your question, since the focus of this
field work will be around identifying species who occupy different zones.


Once the question has been developed, you will be expected to construct a GOOD HYPOTHESIS!
o A good hypothesis is written as an “if ..then…” statement, is both measurable and
testable through this field work!
Each team of students will follow proper data collection techniques and use a transect to collect
data on an intertidal habitat. They will carefully and accurately record their data in both tables
and graphs and will thoroughly explain how their findings inform the hypothesis. (Does the
data support the hypothesis or not?)
The lab write up will have all of the components of a full report, including solid research on the
organisms which you have selected to be the focus of your investigation and the habitat.
Include details of their life-cycle, habitat interactions, food web, biotic interactions and physical and social
adaptations . You are expected to use the vocabulary of environmental science in your paper, and
demonstrate through your writing that you understand what each of the terms mean.
The format will be as follows:
1. Abstract: summary of field investigations and findings.
2. Research: Background information about the habitat and the species which are the
focus of your report.
3. Question: The one being addressed in this report.
4. Hypothesis: In proper format which addresses the question.
5. Experimental Design: What did you do, and how did you do it? Include enough detail
that someone could follow your instructions and repeat your procedure.
6. Data/Evidence: Tables, graphs, diagrams, any observations taken from the field.
7. Results and Conclusions: Carefully discuss all of your findings, explain what you have
discovered to be true how it informs your understanding and evaluate your hypothesis.
Be sure to state if your hypothesis was supported by your data or not.
8. Next Question: Include a new question which you now would like answered, now that
you have found some answers through this lab.
Your report must have all sections clearly labeled and must be organized in the order indicated
above.
It must be typed (12 font, double spaced, New Times Roman) Data tables and graphs MUST be
prepared through word or “excel”. See me if you need help with this. Your work must be neat and
complete. Proof read your work to ensure that you have said what you meant to say. Be clear and
concise!
o
o
You must include a page with proper citations for all of your research sources. (Please you
MLA format)
You are being provided with the rubric! Use it!
Abstract
This study is designed to define the biotic and abiotic characteristics found in a rocky intertidal ecosystem;
to observe interactions between select living organisms and between themselves and their environment,
and analyze which environmental and competitive factors may influence the particular pattern of density,
diversity or zonation found at your study site. The transect method and statistical analysis used for
sampling population abundance and diversity in this activity is applicable to many other coastal and
terrestrial habitats.
Objectives of Field Work and Lab Report
1. Recognize the effect common physical and chemical factors have on rocky intertidal ecosystems.
2. Become familiar with the dominant inhabitants of rocky shores.
3. Recognize some of the most obvious adaptations of marine organisms to desiccation and wave action in
rocky shores.
4. Recognize vertical zonation in rocky intertidal communities.
5. Quantify species diversity and abundance.
Introduction
Ecologists have been aware of vertical zonation in intertidal habitats since the early 1800's, and noticed
that organisms found between the high and low tide marks seemed to vary in a consistent way. For
example, periwinkles might be found in the upper splash zone, gooseneck barnacles and mussels in the
middle intertidal, and sea hares and octopus in the lowest levels. Even then, scientists were beginning to
realize the strong influence that climate, ocean conditions and coastal geology had on living organisms
and on where life became distributed along our coasts.
We will attempt to document this effect by running a transect line from high to low levels in the local
intertidal habitat, and comparing abundances of the various species along that transect. A transect will be
used because it is impossible to count every living and non-living thing in an ecosystem. Transects that
are in a defined area and permanently established can allow comparison between seasons or years over
time. The transect has to be big enough to accurately characterize the biotic and abiotic factors of the
ecosystem and is determined by the living members in the ecosystem.
We will collect population density estimates for about a dozen key intertidal species, extending from dry
rocks in the splash zone to partially covered pools in the low tide zone. Proper identification of the plant
and animal species is critical. The information obtained should be used as the basis for further discussions
dealing with the abiotic and biotic factors (and human influences) that affect the distribution and species
diversity of intertidal organisms.
Background research information links
Pathfinder Science - Real sampling projects around North America
http://pathfinderscience.net/
MBL Marine Animals Database
http://www.mbl.edu/marine_org/marine_org.php?func=browse&myID=D1
West Coast Rocky Intertidal Habitats
http://bonita.mbnms.nos.noaa.gov/sitechar/rocky.html
Rocky Intertidal Ecology (all coasts)
http://life.bio.sunysb.edu/marinebio/rockyshore.html
Marine Biology Web links
http://biology.fullerton.edu/biol319/marine_bio.html
-marinebota
NOAA's National Ocean Service - extensive links
http://oceanservice.noaa.gov/
Materials - For each team of 8-10 students














Five gallon buckets
Zip lock bags and grease pencils
Field guides
Collecting jars
Hydrometer (or refractometer)
Celsius thermometer
100ml plastic Graduated cylinder
1 m or 1/4 m Quadrats or hula hoops
Chemical test kits or electronic probes (pH, dissolved O2)
100m tape measure or marked nylon line
Tide Chart
Shallow plastic pans
Hand lenses
Sharp eyes and minds plus a positive attitude!
Rocky Intertidal Survey
Rocky Intertidal Transect Survey
Abstract
This study is designed to define the biotic and abiotic characteristics found in a rocky intertidal
ecosystem; to observe interactions between select living organisms and between themselves and
their environment, and analyze which environmental and competitive factors may influence the
particular pattern of density, diversity or zonation found at your study site. The transect method
and statistical analysis used for sampling population abundance and diversity in this activity is
applicable to many other coastal and terrestrial habitats.
Objectives
1. Recognize the effect common physical and chemical factors have on rocky intertidal
ecosystems.
2. Become familiar with the dominant inhabitants of rocky shores.
3. Recognize some of the most obvious adaptations of marine organisms to desiccation and wave
action in rocky shores.
4. Recognize vertical zonation in rocky intertidal communities.
5. Quantify species diversity and abundance.
Introduction
Ecologists have been aware of vertical zonation in intertidal habitats since the early 1800's, and
noticed that organisms found between the high and low tide marks seemed to vary in a consistent
way. For example, periwinkles might be found in the upper splash zone, gooseneck barnacles and
mussels in the middle intertidal, and sea hares and octopus in the lowest levels. Even then,
scientists were beginning to realize the strong influence that climate, ocean conditions and coastal
geology had on living organisms and on where life became distributed along our coasts.
We will attempt to document this effect by running a transect line from high to low levels in the
local intertidal habitat, and comparing abundances of the various species along that transect. A
transect will be used because it is impossible to count every living and non-living thing in an
ecosystem. Transects that are in a defined area and permanently established can allow
comparison between seasons or years over time. The transect has to be big enough to accurately
characterize the biotic and abiotic factors of the ecosystem and is determined by the living
members in the ecosystem.
We will collect population density estimates for about a dozen key intertidal species, extending
from dry rocks in the splash zone to partially covered pools in the low tide zone. Proper
identification of the plant and animal species is critical. The information obtained should be used
as the basis for further discussions dealing with the abiotic and biotic factors (and human
influences) that affect the distribution and species diversity of intertidal organisms.
Background research information links
Pathfinder Science - Real sampling projects around North America
http://pathfinderscience.net/
MBL Marine Animals Database
http://www.mbl.edu/marine_org/marine_org.php?func=browse&myID=D1
West Coast Rocky Intertidal Habitats
http://bonita.mbnms.nos.noaa.gov/sitechar/rocky.html
Rocky Intertidal Ecology (all coasts)
http://life.bio.sunysb.edu/marinebio/rockyshore.html
Marine Biology Web links
http://biology.fullerton.edu/biol319/marine_bio.html
-marinebota
NOAA's National Ocean Service - extensive links
http://oceanservice.noaa.gov/
Materials - For each team of 8-10 students















Five gallon buckets
Zip lock bags and grease pencils
Field guides
Collecting jars
Hydrometer (or refractometer)
Celsius thermometer
100ml plastic Graduated cylinder
1 m or 1/4 m Quadrats or hula hoops
Chemical test kits or electronic probes (pH, dissolved O2)
100m tape measure or marked nylon line
Table of random numbers (optional)
Tide Chart
Shallow plastic pans
Hand lenses
Sharp eyes and minds plus a positive attitude!
Transect Procedure
1. Spend some initial time surveying the study site, looking for obvious bands of zonation and
selecting the general area for your first transect. As a team, decide on about twelve "key species''
of plants and animals to census. Not all organisms will be present in every zone - some will be
specialists found only in the Splash zone, but will be there in obvious abundance - some will be
present in all zones, such as small scavengers. Make sure you include at least one marine plant in
each of the zones - they represent food available for grazers.
2. Make your selections based on the range of distribution of each species within the intertidal, its
abundance, and ease of identification. Remember that many of these animals are small, often
camouflaged, and may be hiding. Get down on your hands and knees for a closer look. Be sure to
examine the undersides of rocks (please replace them in their original position), ledges, and even
blades of algae when choosing which species are most dominant along your WHOLE selected
transect line.
3. Use your field guides and test each other to make sure that everyone on the team can identify
these organisms with equal accuracy.
4. Extending your tape measure (or rope) perpendicular to shore, begin at splash zone and
extending outwards towards the ocean for 100 m. You will need to sample TEN quadrat areas
along the transect line. Secure your tape at either end. Based upon the length of the section, the
interval to the next quadrate can be either:
a) standardized, for seasonal or yearly comparisons - divide the transect length by ten and place
quadrats evenly along the line OR
b) randomly placed, using a random number table to measure off how many inches from the edge
of the latest quadrat the NEXT quadrat should be placed along the line... OR
c) randomly placed, by throwing a small rock over your shoulder to establish where along the line
you will begin your next transect square. Wherever it lands, place the beginning of your next
quadrat in the same relative place along the transect.
5. Identify and count the individuals of each key species within the quadrat. If the number of
individuals of a species is too large for convenient counting (over 100), put "100+"). Mark data in
data table #1.
6. Continue down towards the ocean until you have 10 quadrats from one transect.
7. Collect as much information as you can relating to such factors as substrate (silt, small rocks,
algae-covered boulders, etc.), food preferences, feeding behavior, and associations with other
plants and animals, which may be helpful in understanding the role of the plant or animal in the
intertidal community.
PROCEDURES FOR COLLECTING ABIOTIC DATA
1. Sketch the general coastline, include prominent features such as exposed rock groups, lines of
delineation between tidal zones, man made alterations, etc.
2. Sketch a preliminary drawing of your team's study area, designating the direction & location of
your transect line and the quadrat outlines.
3. At selected points along your transect, determine environmental conditions such as water
temperature, salinity, pH, dissolved oxygen concentration, and duration of exposure to air. Record
the data on your data sheet. Once the transect and quadrates have been laid out, record the
following data for transects in each of the four zones:
4. Estimate the % of time each quadrat is submerged, through a 12 hr tidal change (low to high to
low
again) and record the results on your data sheet.
Temperature Procedure

Record water temperature from representative quadrats within each of the four tidal zones
with a centigrade thermometer and record your results on the data sheet.
Salinity Procedure



Fill a 100ml plastic graduated cylinder with a sea
water sample from representative quadrats within
each of the four tidal zones.
Gently float a hydrometer in the cylinder, to measure
the density of your sample. The diagram will help you
read the hydrometer. Record the density here.
_________________
Use the hydrometer-temperature graph to read the
salinity.
To Find Salinity:
a. Find the correct water temperature on graph.
b. Follow the temperature line over until you meet the correct
hydrometer density line.
c. From this point drop straight down and read off correct
salinity of your sample in parts per thousand (0/00).
Dissolved
Oxygen And Ph Procedures

Follow the directions on the chemical test kits to determine the dissolved oxygen content
and pH of your water sample. If you are using electronic probes, make sure they are
properly calibrated before using and take your dissolved oxygen and pH measurements in
the deepest area of the quadrat.
Survey Tips
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

Move quickly down the transect: the first quadrats may take the longest, as you begin to
work out a standard procedure. Make sure your other team members use the same
techniques when sampling each quadrat, to prevent bias.
Be careful of splashing water on electronic probes - they are VERY expensive!
Agree as a group how you will deal with organisms that fall part way into the quadrat.
DATA COLLECTION SHEET - ROCKY INTERTIDAL SURVEY
Transect # _________________
Date: _____________________ Location:
________________________________________
Predicted low tide (from tide chart): ___________ m (___________ ft)
Tide level at beginning of survey: ___________ m % of time submerged ________________
Beginning Time _______ Ending Time _______
General weather conditions (sun, rain, ocean conditions):_____________________________
__________________________________________________________________________
Wave Height and Action: (from daily weather report)________________________________
Splash Zone Temperature: _______ oC Salinity: ______ o/oo DO2: _______ pH: _______
High Tide Zone Temperature: _______ oC Salinity: ______ o/oo DO2: _______ pH: _______
Mid Tide Zone Temperature: _______ oC Salinity: ______ o/oo DO2: _______ pH: _______
Low Tide Zone Temperature: ________ oC Salinity: ______ o/oo DO2: _______ pH: _______
Table 1. Dominant intertidal species found in transect #___ at _________ on
_________
# of Organisms per Species
Name of Species
QUAD QUAD QUAD QUAD QUAD QUAD QUAD QUAD QUAD QUAD
1
2
3
4
5
6
7
8
9
10
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
Data/Observations
Once all the data had been collected, the team should first decide which quadrats fell within each
tidal zone (ex: Quadrats 1 +2 - Splash zone; quadrats 3 + 4 = High Tide Zone; quadrats 5, 6, 7, 8
= Mid Tide Zone; quadrats 9 + 10 = Low Tide Zone.) Add all the data from similar quadrats
together and average the data by the number of quadrats sampled (Mid Tide Zone = 45 mussels,
68 mussels, 54 mussels, 66 mussels/4 = a mean of 58 mussles/ 1/4m quadrat.)


If your team has had the chance to collect data from several transects at the study site,
you should pool (add up) the numbers of individuals at similar quadrats before calculating
the average, to increase the size of the data collected. Remember, the more data, the
better the results...
Your teacher may want to pool the data from ALL teams, the greatly increase the data
numbers and increase the accuracy of significant statements about abundance and
diversity of species at the site. You may have to wait until everyone turns in their data and
has a group discussion on the results before beginning final calculations and the creation
of a lab report.
Organize the data you have collected from each zone into clearly understandable tables, graphs,
or charts.
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

Make sure all data tables and graphs are properly labeled, with date and location included.
Make sure to list the scientific and common name for each of your dominant species.
Decide whether you're going to present your data by charting ALL DATA from station #1,
ALL DATA
from station #2, etc. or show a comparison side by side - Distribution and Abundance of
Species #1 at Stations #1, #2, #3, etc.
Calculations
Use the following equation to calculate the species diversity for combined transects within each
zone (ex. species numbers for quadrats #1-2 are combined, since both fell within the splash
zone.)
Simpson's Diversity Indices
There is statistical testing for populations that do NOT follow a normal distribution (and this
includes most populations in the wild.) These are called nonparametric statistics. Simpson's
Diversity Indices is a non-parametric statistical test commonly used by wildlife biologists to
document differences between populations and show trends in communities over time. It is
frequently used when describing differences between communities (or tidal zones.) It answers the
question: if 2 individuals are taken at RANDOM from a community, what is the probability that
they will be the SAME species????


The closer the answer is to 1.0, the more Homogeneous the community
-Only a few species present (low diversity), but all in very large numbers (high
abundance)
The farther away the answer is from 1.0, the more Heterogeneous the community.
-Many species present (high diversity), but only a few of each species (low abundance)
We will be comparing the species diversity and abundance between the 4 intertidal zones, looking
at how homogeneous or heterogeneous the community structure within each zone seems to be.
Simpson's Diversity Indices (D), where
Analysis
Your team will be completing a collaborative formal report as a culminating task. Refer to the
"Report Format" for proper style and design. Each member of a team will turn in a separate
report, consisting of an Introduction, Materials, Procedures, and Results which are identical to each
others but including individual, unique analysis and conclusion sections.
After the class discussion and sharing of data, your team needs to meet at lunch or in the library
for a good 45 min to an hour to rough out the first draft TOGETHER. Someone with good typing
skills should agree to type up the group portion of the report and make copies for everyone and
another person with good experience in computer tables and graphs should format the data on
computer and also provide copies for the team.
Everyone works on his or her own analysis and conclusion. This is the heart and soul of any report
or survey. Once you've calculated the Diversity Index for each of the four intertidal zones, use
your final answers to help substantiate your findings. First, summarize the data from tables and
graphs in words to validate your arguments. This does not mean a parrot-like recitation of all the
data when you've already given it in a table. It means: look at the data from the experiment for
trends, refer to your actual data numbers to show a point. Don't just use qualitative terms like:
"Zone 1 had a larger amount." Better said: Zone 1 had 33% less algae. You've taken the raw data,
performed a calculation, and used it to underscore a trend.
After you've summarized the data, decide which errors are relevant - which were so large as to
invalidate the survey? How might have your observations affected your results? Analyze WHY you
got the results you did ... BE SCIENTIFIC ! THINK!!! This is your chance to show you understood
the field study. If there are ways to improve on the procedure, mention them. Your data should be
interpreted, critically evaluated, and compared to other group's results as well as previous
research. Whereas your data table and graphs present the "news," the analysis section contains
the "editorial." In the analysis, examine the amount and possible sources of variability in your
data, including experimental error. Examine your results for bias and evaluate its effect in data
interpretation. Develop arguments for and against your hypotheses and interpretations. Do not
make generalized statements that are not based on your data, known facts, or reason. Be sure to
relate your findings to other studies and cite those studies. Draw positive conclusions from your
study whenever possible.
Some ideas to consider:
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
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
The general trends of distribution of intertidal plants and animals at your study site.
What apparent physical and biological factors can you suggest for these distributional
patterns?
Discuss the relationship between species abundance and species diversity at your site.
Is there a relationship between generalist and specialists in terms of species abundance in
particular zones and climactic conditions?
Look closely at the abundance of dominant species at each zone, abiotic factors present,
the food requirements, predatory interactions and competition at work in each zone and
ANALYZE the reasons behind each species abundance and zonal preference.
The team should bring the final drafts together the day before the lab is due to distribute, add
their personal analyses and conclusions and turn in the completed reports in.
__________________________________________________________________
TEACHER TEMPLATE
TITLE: Rocky Intertidal Transect Survey
NAME, AFFILIATION: Anne Maben, AP Science Coach, Los Angeles County Office of Education
CORRELATION TO TOPIC OUTLINE IN ACORN BOOK:
E. The Biosphere: Organisms; populations and communities; exponential growth, carrying
capacity; ecosystems and change
IV. Environmental Quality: effects of pollutants on aquatic systems (optional)
Correlation to National Standards
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Science As Inquiry, CONTENT STANDARD A: Students will be performing hands-on
scientific inquiry and experimental design
Physical Science, CONTENT STANDARD B: Students will be analyzing the abiotic factors of
waves, light and heat on ecosystems through interactions of energy and matter.
Life Science, CONTENT STANDARD C: Students will be directly investigating the
interdependence of organisms, the organization in living systems and the behavior of
organisms.
Earth and Space Science, CONTENT STANDARD D: To properly analyze the abundance and
distribution of living organisms in the target ecosystem, students have to understand
energy transfer in the earth system and geochemical cycles.
Science and Technology, CONTENT STANDARD E: In using a variety of sampling
equipment and statistical analyses, students will need to understand the abilities of
particular technological designs.
Science in Personal and Social Perspectives, CONTENT STANDARD F: Students will be
documenting population growth and environmental quality in the target ecosystem, as well
as observing human impacts on the environment.
INTRODUCTION:
While this field study is coastal in nature, the same skills and concepts can be applied to most
other inland terrestrial ecosystems. Before students begin any ecosystem investigation, make sure
the students have a deep understanding of both the biotic and abiotic factors that characterize the
particular ecosystem to be studied.
Field studies should be multi-dimensional - encompassing conceptual learning, experience with
scientific equipment, statistical analyses, observational and research techniques and a great deal
of collaboration and inquiry. While field studies definitely take more time than an ordinary lab, a
well-planned and executed field study will yield tremendous "bang-for-the-buck" and help to
prepare students for case study questions on the Advanced Placement exams. Field studies help
students participate in "real" science, especially if the results are collected with established
protocols and reported to local government or environmental agencies.
Students should be well-prepared to get the most out of every experience and held accountable
for learning. Field studies are also excellent for building collaborative skills and reinforcing that
science does not occur alone - it's a team effort.
GROUP SIZE:
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
24 - 36 students (3 - 5 teams)
Each Transect team = 8 - 10 students
One chaperone for each team, plus instructor
ACTIVITY LENGTH: 2 classroom periods and 1 fieldtrip day
PREPARATION AND PREP TIME:
Students need at least



One period to review and model proper use of sampling equipment and select teams and
habitat to study.
- One half or full day field excursion (or school yard study) to collect transect data.
One period for online or library research and collaboration in teams to analyze the data.
Optional: One period to present the data in groups (or simply turn in group lab reports)
CLASS PERIOD PRIOR TO THE TRANSECT STUDY:



Spend time calling students up to have them "demonstrate" the proper technique for any
sampling tools used. Elicit comments and suggestions from the class and discuss WHY
techniques need to be standardized. Go over common animals and plants likely to be
found along the transects, either on the web, through a PowerPoint or with field guides.
Divide students in transect teams and have them select roles for each team member.
Go over a map of the site on the overhead and indicate where each team will be stationed.
MATERIALS/EQUIPMENT:
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
Five gallon Buckets marked with team numbers to carry equipment in. (Cleaned dissecting
buckets with handles work well...)
Zip lock bags and grease pencils to mark any voucher specimens for later identification.
Appropriate field guides for every group
Water Sampling Equipment
o Salinity sampling: Collecting jar, Hydrometer + Graduated cylinder or a
refractometer
o Chemical test kits or electronic probes (pH, dissolved O2 - optional: Phosphates,
Nitrates, heavy metals, chlorine, dissolved solids)
Transect Sampling
o 100m tape measure
o 1 m or 1/4 m Quadrats or hula hoops
 PVC piping and connecting "elbows" to make 1 meter or 1/4m square
transects that can be disassembled and assembled quickly. Drill holes in
the pipes so they won't float in the water...OR
 Hammer used railroad spikes or wooden stakes into the substrate and run
string between them to create 1 meter or 1/4m squares... OR
 Use hula hoops that you've drilled holes in...
o Shallow plastic pans for temporary observation of animals
o Hand lenses for plant and animal identification
CLASS PERIOD AFTER THE TRANSECT STUDY:



Give the students time to discuss their findings as a class and share data to pool.
Review calculations involved and report format.
Emphasis that this is a team report.
o Everyone on each team will be expected to turn in identical sections for the
beginning of each report and then add individual analyses and conclusions.
o All team members will receive the same grade for the identical portions: it's the
analysis and conclusion that's the most important piece and is where a teacher will
have a chance to assess their understanding.
o Cuts down grading considerably and raises the bar on report-writing.
SUPPLIERS:
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Surveying tape and PVC piping at any Home Depot or Lowe's
Combination thermometer/hydrometers can be bought at any tropical fish store, more
cheaply than through catalogs. (about $6.00)
Tide charts are available for a nominal fee from State Fish & Wildlife Offices, bait or dive
shops or the internet. Tide levels, wave and wind conditions are given daily in the
newspaper.
Ben Meadows Catalog - Terrestrial and Aquatic Sampling Equipment
http://www.benmeadows.com/
Aquatic Ecosystems,Inc
http://www.aquaticeco.com/index.cfm
LaMotte - Marine & Aquatic Sampling Equipment
http://www.lamotte.com/
Wards Natural Science - Science Supplies http://wardsci.com/Default.asp
SAFETY & DISPOSAL:
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Make sure students are wearing the proper footwear to prevent spills.
Make students aware of "rogue" waves that could pull them into the ocean when sampling
the low tide zone - never sample with your back to the waves nor sample alone.
Make students aware of wind chill when sampling on lakes or near oceans - always wear a
"layered" look.
Students should treat animals carefully if temporarily removing them for counting or
observation. Always replace animals where they were found, with their habitat intact.
Make sure you have a state sampling permit if you are removing any animals or plants to
the classroom or for voucher specimens. Apply for one through your District or County
Science Consultant. Usually, no collection is allowed in reserves, even if you DO have a
permit.
LINK TO STUDENT ASSIGNMENT & PROCEDURE
SPECIFIC TIPS:
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Be sure to check tide charts well in advance of your trip, so that sampling can be done in
daylight hours and the desired ecosystem will not be covered with water.
Begin your survey of the rocky shore at the SPLASH ZONE if the tide is ebbing (going out.)
Begin your survey of the rocky shore at the LOW TIDE ZONE if the tide is flowing (coming
in.)
Each team should consist of about 8-10 students: half of the team will sample and observe
the abiotic factors influencing study site and the other group will sample and observe the
living organisms. Once all the quadrats from one transect have been sampled, groups
should change jobs in order to survey the second transect. In class, all teams can pool
their data from quadrats in similar zones to obtain a more accurate analysis.
Make sure the whole class has agreed on one method to use consistently to lay the
quadrats!!!
Equipment:
Most equipment can be easily made instead of bought through expensive catalogs.
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Measuring tapes can be made from a 100m length of nylon line or tough twine can be
knotted at 1m intervals or marked with permanent ink.
"Field guides" can be researched and created by students that include drawings and info
on common organisms expected at the site. Laminate them at school to make them
waterproof.
Quadrates can be easily made and used for years by using:
o PVC piping and connecting "elbows" to make square transects that can be
disassembled and assembled quickly. Drill holes in the pipes so they won't float in
the water...OR
o Used railroad spikes or wooden stakes that can be hammered into substrates and
have tough twine run between them to create square transects... OR
o Use hula hoops that you've drilled holes in...
Buckets, water samplers, observation trays, voucher jars can be recycled from science
suppliers dissection buckets, soda bottles, yogurt, and butter containers.
POTENTIAL PROBLEMS:

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Lack of time: Students can take too long to count organisms and the tide can come in
and cover quadrats before they are finished. Be sure the students are well-prepped in
using equipment and have done simulations in class before they arrive on site. A wellprepped class can coordinate data collection in an amazing rapid fashion and have plenty
of time to spend actually observing behavioral changes due to water level fluctuation or
species interactions.
Lack of focus: Students that feel unprepared in the techniques of sampling and don't
know how to effectively collaborate with others on a task may simply mill around and feel
adrift. Make sure everyone has a specifically assigned task and monitor each team closely
throughout the survey.
Hunger & Thirst: Normal teenagers burn up over 3000 calories on strenuous field trip!
Ask each student to bring as much as 2 lbs of food + plenty of water/per student for a
day-long trip - and low in processed sugar.
Accidents and sickness: always have a chaperone drive their own car to a study site, so
they can act as the "pace car" and attend to an ill student if necessary, without having to
abort the entire trip
POST-SURVEY ANALYSIS & TYPICAL DISCUSSION QUESTIONS:
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Discuss why it is important to record weather conditions at the study site.
What were some of the structural adaptations to incoming waves that you observed in
your quadrat species?
o Were there any behavioral adaptations to the waves that you noticed?
What kind of problems do invertebrates and seaweeds have to deal with when exposed to
air, besides drying out?
o Were there any adaptations to exposure to air that you could observe?
How do you account for the differences in temperature, salinity, the number of species,
and the abundance of organisms in each of the tide pools that were sampled?
Did you observe any particular patterns in the distribution of different species of organisms
as you moved from the low tide level to the highest level, one that is covered only by very
high tides?
Give some possible differences in what you would have observed if the weather conditions
were different from today's.
How did the distribution of species in your transects compare with the distribution of the
same species in transects made by the other groups in different sections of the same
intertidal zone? Were there any species that were found in only some of the transects?
Come up with some hypotheses to explain any differences in zonal distribution and/or
presence or absence of organisms on the different sections of the study site.
OTHER POSSIBLE ASSESSMENTS:
Field studies lend themselves to rich discussions, during a post-trip sharing of data and
experience.
Typical individual assessments include:

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a free-response question on a test, describing a similar study site to analyze and sample
data to work with
written critiques of the day in their journals
team presentations of their data and analysis, along with accompanying digital photos
projected on TV's or an LCD projector often stir additional discussion of the results.
Rubric for Field Studies:
At the Field Study Site
Good
Satisfactory
Needs
Improvement
Brought all
needed
materials and
Preparedness
was eager &
ready to
work.
Brought
most
needed
materials
and was
ready to
work.
Brought most
needed
materials but
took a while to
settle down and
get to work.
Forgot needed
materials and
took a long time
to settle down
and work.
Almost
always
listened to,
shared with,
and
Working with supported
the efforts of
Others
others. Tried
to keep
people
working well
together.
Usually
listened to,
shared
with, and
supported
the efforts
of others.
Did not
cause
"waves" in
the group.
Sometimes
listened to,
shared with, and
supported the
efforts of
others, but at
times, was uncollaborative.
Rarely listened
to, shared with,
and supported
the efforts of
others. Was not a
good team
player.
Focus on the
task
Focused on
the task
Consistently
and what
stayed
needed to
focused on
be done
the task and
most of the
what needed
time. Other
to be done.
group
Very selfmembers
directed.
could count
on you.
Focused on the
task and what
needed to be
done some of
the time. Other
group members
sometimes had
to nag or
remind you to
stay on-task.
Rarely focused on
the task and what
needed to be
done. Let others
do the work.
Problemsolving
Actively
looked for
and
suggested
new solutions
to problems.
Did not suggest
or refine
solutions, but
was willing to
try out solutions
suggested by
others.
Did not try to
solve problems or
help others solve
problems. Was
uninvolved.
Category
Excellent
Refined
solutions
suggested
by others.
During Class Discussion and Group Write-up
Routinely
provided useful
ideas when
collaborating
and in
Contributions
discussion. A
definite leader
who
contributed a
lot of effort!
Usually
provided useful
ideas when
collaborating
and in
discussion. A
strong group
member who
tried hard!
Sometimes
provided
useful ideas
when
collaborating
and in
discussion. A
group member
who did only
what is
Rarely
provided
useful ideas
when
collaborating
and in
discussion.
Often refused
to participate
and preferred
required.
to work alone.
Experimental
design left
some
unanswered
questions.
Most variables
were
controlled,
sufficient # of
samples/
replicates were
made.
Experimental
design left
unanswered
questions. An
attempt was
made to
control
variables and
minimal
observations
and # of
samples/
replicates were
made.
Experimental
design was
poorly
executed and
did not gather
useful data or
observations.
Only a small
amount of
data/
replicates
were made.
Scientific
Concepts
Report
illustrates an
accurate and
thorough
understanding
of scientific
concepts
underlying the
study.
Report
illustrates an
accurate
understanding
of most
scientific
concepts
underlying the
study.
Report
illustrates a
limited
understanding
of scientific
concepts
underlying the
study.
Report
illustrates
inaccurate
understanding
of scientific
concepts
underlying
the study.
Data
Professional
looking and
accurate
representation
of the data in
tables and/or
graphs.
Accurate
representation
Accurate
of the data in
representation
written form,
of the data in
but graphs or
tables and/or
tables were
graphs.
poorly labeled
and titled.
Data were not
shown OR
were
inaccurate.
Calculations
All calculations
were shown
and analyzed
with
appropriate
and
understandable
statistics.
Some
calculations
were shown
and analyzed
with
appropriate
and
understandable
statistics.
Some
calculations
were shown.
They were not
analyzed with
inappropriate
statistics that
don't further
understanding.
No
calculations
are shown OR
results are
inaccurate or
mislabeled
and not
statisticallyanalyzed.
Background
Sources
Several
reputable
background
sources were
used and cited
correctly.
Material was
translated into
student's own
words.
A few
reputable
background
sources were
used and cited
correctly.
Material was
translated into
student's own
words.
A few
background
sources was
used but were
cited
incorrectly.
Material was
translated into
student's own
words.
Material was
directly
copied from
other sources
and/or
background
sources were
cited
incorrectly.
Conclusion
Conclusion
included
whether the
findings
supported the
hypothesis,
possible
sources of
error, and
what was
learned from
Conclusion
included
whether the
findings
supported the
hypothesis and
what was
learned from
the
experiment.
Conclusion
included what
was learned
from the
experiment.
No conclusion
was included
in the report
OR showed
little effort
and reflection.
Experimental
design was
wellconstructed.
Variables were
Experimental controlled,
extensive
Design
observations
and # of
samples/
replicates were
made.
the
experiment.
VARIATIONS AND EXTENSIONS:
Let students choose their study site. Practical coastal study sites might include:
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A sandy beach (quadrats could be samples in apparently homogeneous areas along a
transect that is parallel to the beach or through seemingly heterogeneous communities
along a transect that is perpendicular to the shoreline at interface between waves & sand,
dunes, subtidal directly offshore, backshore area, etc.)
An estuary (homogeneous transect within the same zone or a sloping heterogeneous
transect along different regions of an estuary marsh area, tidal mud flat, mouth of river
source or opening to ocean, mid channel, etc.)
A tidepool (homogenous transects within the same tide level)
Pier pilings in a protected bay or ocean (10 homogeneous quadrats on similar pilings, all
nearby in the same area; or 10 heterogeneous quadrats - starting close to shore and
continuing on successive pilings to the end of the pier)
Terrestrial study sites that might be chosen could include:

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Riparian habitat along a river bank or pond, with perpendicular transects running from the
water back across several areas.
Meadow, field or prairie transects, looking for homogeneity. Standard measure transects
can be laid along random compass headings and vegetation and insect life identified along
a 1/2 meter strip on either side of the tape.
Forests can be measured for species dominance and abundance using the point-quarter
method of sampling, which involves additional statistical analysis.
Let students select sampling methods

Students should have the choice of selecting the most efficient and statistically sound
method of sampling species distribution, depending on whether their study site
o should vary greatly within a short distance, primarily in a vertical fashion;
o is relatively homogeneous in composition and varies little either vertically or
laterally, except for wide swings in tide levels;
o in a slow but steady fashion, with increasing distance from a water covered region.
References/Resources (texts & web links)
Virtual Intertidal Fieldtrip by Bishops College
http://redbaron.bishops.ntc.nf.ca/wells/fieldtrp/field.htm
Virtual Owl Limpet Tidepool Study
http://edweb.sdsu.edu/triton/tidepoolunit/OwlLimp/OwlLimp.html
Audubon Field Guide to California (Amazon.com) - contains habitat, climate, geology, all common
terrestrial AND aquatic plants, animals, fungi and plankton, along with National Park and State
Reserve information.
Other similar regional Audubon Guides
Field and Lab Methods for General Ecology - Brower, Zar, & Von Ende (Amazon.com)
Sampling Design & Statistical Methods for Environmental Biologists - Green - QH 541.15
Ecological Experiments: purpose, design & execution (1989) - Hairston - QH 541.24
Statistical Methods in Biology (1995) - Norman Bailey - QH 323.5
Techniques for Wildlife Investigations - (1992) - Skalski and Robson - QL752 S52
Marine Biology (2000) - Castro & Huber - ISBN: 0534530826
Oceanography (1999) - Tom Garrison - ISBN: 0070121974
Coastal Marine Zooplankton: Practical Manual for Students (1996) - Todd -ISBN: 0521555337
Sea Challengers Natural History Books
http://www.seachallengers.com/