United States Department of the Interior
NATIONAL PARK SERVICE
George Washington Memorial Parkway
700 George Washington Memorial Parkway
McLean, Virginia, 22101
Chesapeake Watershed Cooperative Ecosystem Study Unit (CW CESU)
And the George Washington Memorial Parkway
Letter of Research Interest (LOI)
Title: Anthropogenic soil disturbance affects and Baseline Inventory of Acari (Mites) for the George Washington Memorial Parkway, McLean Virginia
The GWMP is unique in having documented and preserved many areas of intense human activity and soil disturbance coinciding with nearby pristine natural resources. By sampling inside and outside known soil disturbances, this project seeks to determine if and/or to what degree anthropogenic soil disturbance affect soil fauna diversity and density.
Soil systems throughout the world represent important reservoirs of biodiversity with overall levels of diversity several magnitudes higher than above ground (Heywood 1995).
However, soil systems, in particular the micro-invertebrates, are grossly understudied with the total described fauna of Acari and representing less than 5% of expected true diversity in these groups (Wall et al. 2001). This is an amazing statement since Acari (mites) currently represent one of the best examples of an ancient, mega-diverse Metazoan lineage, comprising ca. 5% of all described species (Wilson & Peter 1988). Although only ~60,000 species have been described, total mite diversity has been estimated up to 10 million species (Walter and
Proctor 1999).
Nature of Work Required
This project will be an intensive survey of the predatory mite fauna in the George Washington
Memorial Parkway system. Taxonomic focus of the survey will include four major superfamilies (and associated families) of mites commonly found in these systems: Bdelloidea
(Bdellidae and Cunaxidae), Erythraeoidea (Erythraeidae and Smarididae), Ascoidea (Ascidae,
Podocinidae, and Ameroseiidae) and Dermanyssoidea (Laelapidae). This is a total of eight mite families that represent most of the predatory mite diversity found in soil and litter habitats. These are chosen because they are the dominant predators in these systems.
There are two main components of this inventory work: extensive field collections and curation. Both are equally time consuming and important to successful completion of the study. Field collections will obtain a vast number of specimens that will be returned to the lab for the curation aspect of the project. Curation includes specimen preparation, identification, imaging, and logging of all taxonomic information into a spreadsheet.
M
ETHODS
The Principle Investigator, collaborators, graduate students, and NPS volunteers will intensively sample soil and litter habitats for predatory mites at four sites of known soil disturbance from distinct historic periods. Since presence of many of these mites may depend on time of year as well as time of day, sampling efforts will extend from March to October and will include traps that will collect nocturnally active species. Sampling methods will

involve litter and soil processing in Berlese funnels, pitfall traps for actively moving species, and visual inspection of rocks, plants, and fallen tree. Each of these methods is described below. The PI and graduate students will make four visits to the DC area (April, June, August, and October) to take samples for the inventory. Local collaborators or NPS volunteers will take samples in March, May, July, and September. Each of the PI’s trips will last seven days.
Berlese funnel extractions. Soil and litter samples are collected into one gallon Ziploc bags (this amounts to scraping litter from a 30cm x 30cm area) and returned to the lab for processing. In each habitat, samples will be taken every 5m along 50m transects in order to allow statistical comparison of all habitats sampled. Transects will be paired at each site with one falling within, and the other falling outside the zone of known soil disturbance. Project will take samples from two sampling sites during each month and sample from four transects at each of these parks. The additional ten samples at each park will involve spot collecting from areas within the forest that exhibit unique qualities for sustaining high levels of diversity, but which don’t fall within any transects.
Pitfall traps . Many of the fast moving predatory species are more commonly collected in pitfall traps because of their propensity to spend time in more open areas of the forest floor
(eg. Rocks, bare spots among litter), which are not typically sampled for litter. The pitfall trap consists of a plastic cup (usually 12-16oz) buried so the rim is level with the surrounding litter.
Hand collection: While out collecting soil and litter samples, the PI and collaborators will examine the undersides of rocks, logs, beneath loose bark on dead trees, and on low lying foliage for the presence of predatory mites. Specimens found inside and outside zones of soil disturbance will be live captured and used for digital imaging and then slide mounted and identified to species.
S TUDY A REA
The mite survey will be collect samples from paired sites in four sites of the George
Washington Memorial Parkway both within and outside of documented soil disturbances dating from the early 1800’s to present. Efforts within each of these study areas will focus on litter and soil samples from the various microhabitats contained within each area.
Project Timeframe
Deadline for responding to this letter of interest is February 15, 2012.
Products
At the end of the project, the PI and collaborators will produce a comprehensive species list in the form of an Excel spreadsheet with complete taxonomic and collection information. This spreadsheet will include information on all taxa collected, including specimens from nontarget groups that have been identified to some taxonomic level by the researchers. A synoptic collection of identified specimens will be provided to the George Washington Memorial
Parkway and will include representatives of all taxa highlighted in the accompanying Excel spreadsheet. The PI will retain a subset of identified taxa from the collections for use as both research specimens as well as a teaching collection for current and future graduate students.
Collection of mite species new to science is the nature of working with mites, and any soil and litter dwelling micro-arthropod groups. New species found within the focal groups will be described in peer-reviewed journals following all protocols for new species description laid out by the International Code of Zoological Nomenclature

( http://www.iczn.org/iczn/index.jsp
). Type specimens will be deposited using a National Park
Service loan agreement. Paratypes will be included in the synoptic collection provided to the
Parkway. Additionally, the proposed sampling is sure to collect numerous non-focal mite groups like Oribatida and other arthropod groups. These would include commonly collected groups like Collembola, Archaeognatha, Diplura, Protura, Psocoptera and numerous families of Coleoptera and Hymenoptera. The PI will make these available using a National Park
Service loan agreement to any specialists wishing to identify them for research in exchange for proper identifications. Such identifications will be forwarded onto the GWMP.
Other scientific information such as species checklists, ecological comparisons of diversity between different habitat types, and overall levels of diversity for the parks will appear in peer-reviewed journal articles.
PI will prepare educational information for GWMP visitors and NPS staff. This material will include a Powerpoint presentation on the soil and litter dwelling mite fauna of the Parkway, numerous digital photos of living mite specimens (when possible), digital photos of each slide mounted specimen taken under the microscope, and lastly all ultra-high magnification digital images taken with the Low Temperature Scanning Electron Microscope (LTSEM). This combination of image will provide a fantastic visual experience for GWMP visitors and NPS staff unaware of the amazing and complex diversity found in the soil and litter of the
Parkway.
Funds Available
Project funds available are $15,000 to $20,000 that includes the CESU overhead rate of 17.5 percent. The project will be funded by the National Park Service.
Contact
Responses of interest should be directed before the closing date to Erik Oberg
( erik_oberg@nps.gov
) or Walter Zachritz (walter_zachritz@nps.gov). Additional questions can be answered by contacting Erik Oberg, Biologist, , George Washington Memorial
Parkway, National Park Service, (703) 289-2542, or Walter Zachritz the NPS CW CESU
Coordinator at 301-689-7108.