Technical Support for Species-at-Risk Surveys and Analyses in Support of Army Environmental Conservation

ERDC seeks applications for Technical Support for Species-at-Risk Surveys and Analyses in Support of Army Environmental Conservation

Background:

Many of the land bases where US Army installations reside are ecologically significant providing refuge for a large number of the nation's threatened and endangered plants and animals. The benefits of biodiversity to the public and the environment have long been recognized and the Army's role as land managers can influence the floral and faunal diversity both within the installation and on nearby lands. Proactive surveys and management of at-risk species, prior to federal listing, can provide critical information for land managers and conservation biologists to make more effective conservation and management decisions and to reduce probability of listing.

Certain taxa, such as freshwater mussels and herpetofaunal (reptile and amphibian) species, have experienced precipitous population declines across the globe and are particularly vulnerable to habitat loss and degradation. As such, land managers, such as the US Army, conducts planning level surveys to understand distribution, relative abundance, and population health of these vulnerable taxa. Work under this proposal will provide research and analytical support to assess distribution of aquatic freshwater mussel and herpetofaunal communities, with the work to take place at two southeastern US Army installations. Information garnered under this proposal is aimed at improving management and conservation of at-risk freshwater mussel and herpetofaunal species throughout their ranges.

Program Description/Objective:

The government seeks research and technical support for planning level surveys and analyses of freshwater mussel and herpetofaunal species occurrence, distribution and relative abundance. Surveys will take place at Fort Johnson, Louisiana and Fort Cavazos, Texas. It is anticipated that results from these analyses will be relevant for improved conservation and management of the focal species, throughout their respective geographic ranges. Details of primary tasks are as follows:

Task 1: Freshwater aquatic mussel community surveys and analyses

Freshwater mussels are known to be one of the most imperiled taxa (Strayer et al. 2004). As such, a large number of mussel species are either federally listed under the endangered species act (ESA) or being considered for federal listing. In particular, there are two freshwater mussel species, the Louisiana Pigtoe (Pleurobema riddelli) and the Texas heelsplitter (Potamilus amphichaenus), currently under review for federal listing that occur near Fort Johnson, Louisiana, with critical habitat that has been proposed within 20 miles of the installation. Understanding the potential occurrence and distribution of the species on Fort Johnson is critical for potential future Section 6 ESA consultation with USFWS. However, due to their cryptic behaviors and challenges associated with taxonomic identification, freshwater mussels are notoriously difficult to survey.

Work under this task will include freshwater mussel surveys throughout Fort Johnson in summer and fall 2024. A minimum of two surveys (summer and fall) will be conducted across a minimum of 8 streams on the installation. Specific survey timing and locations will be decided based on focal mussel species life history, previous survey efforts, and coordination with ERDC-CERL and Fort Johnson Conservation Branch. All survey data, including locations and numbers of individuals of all detected mussel species, will be compiled into a report. Photos and/or voucher specimens will be collected to verify species identities.

Task 2: Herpetofaunal community surveys and analyses

Globally, an estimated 36% of reptiles and 41% of amphibians (collectively herpetofauna ) are considered at risk of extinction (IUCN 2019) due to a variety of causes including habitat loss, disease, introduced species, and environmental contaminants (Gibbons et al. 2000). As such, an increasing number of herpetofauna have been listed or petitioned for listing under the Endangered Species Act (ESA). Previous herpetofaunal survey effort on Fort Cavazos, Texas documented a diverse community of reptiles and amphibians of 48 species, including several declining species and one state listed species. An updated survey is required to understand current distribution of herpetofaunal species across the installation and document any potential trends in population status. Work under this task will include a combination of visual encounter, trapping, artificial cover object, and acoustic surveys for herpetofauna on Fort Cavazos during spring and summer 2024. Survey results should be assembled into a final report summarizing and interpreting the results of these surveys, which can be extrapolated to guide species management and facilitate incorporation into the Fort Cavazos Integrated Natural Resources Management Plan.

Monthly surveys will be conducted across the general active season (April - July) for reptiles and amphibians in 2024. Survey locations will be determined in consultation with ERDC-CERL and Fort Cavazos Natural Resources branch staff, based on each species' natural history and availability of suitable habitat. A variety of methods will be employed to detect herpetofauna including timed visual encounter surveys, road cruising survey, aural (frog call) surveys, and artificial cover objects.

All survey data, including locations, numbers of individuals and detection method of all detected reptile and amphibian species, will be compiled into a final report.