Allegheny Pools Mussel Project
Freshwater mussels are considered the most imperiled fauna in North America, with approximately 70 percent of the fauna considered imperiled. During the past 100 years, over 30 species are known to have gone extinct with at least 70 others in danger of extinction. Several of those species are endemic to the Allegheny River system, where mussel beds are threatened by habitat loss and degradation.
Mussels have an important ecological value. Mussels are a vital link in the food chain as food items for many animals including muskrats, raccoons, and otters. Mussels are filter feeders and therefore improve water quality by straining out suspended particles and pollutants from the water. A single mussel can filter several gallons of water per day!
Mussels serve as good indicators of ecosystem health. Mussels typically remain in one place for most of their life and require good water quality, sediment types, and physical habitat. Biologists often use mussels as "biological monitors" to indicate past and present water and sediment quality in lakes and streams. Gradual mussel die-offs or sudden mussel kills are signs of water pollution problems and other environmental health concerns. Stable, diverse mussel populations typically indicate clean water and a healthy aquatic system.
Freshwater mussels require host fish in order to reproduce. Mussel larvae, called glochidia, are parasitic and need a host fish (or salamander) to attach onto and develop, before falling off as a juvenile mussel. This essential life stage is not known to cause any harm for the host fish, but is critical for upstream dispersal of mussels. Some mussel species require a specific fish to act as a host, so if that fish species is absent, the mussel cannot successfully reproduce.
The Allegheny River was historically the richest stream in PA for freshwater mussels, with over 50 species known to inhabit the river.
Habitat disturbance and degradation have triggered the decline and loss of mussel communities in the Allegheny River. In the lower Allegheny River, the lock and dam structures changed the river from free-flowing, well-oxygenated riffles and runs into a series of deep slower flowing pools or lakes. The resulting changes in water depth, water currents, temperature, and restructured fish and algal communities can negatively affect freshwater mussels. Slow water flow allows suspended sediments to drop out of the water column and settle onto the river bottom, which often buries entire mussel beds. Furthermore, dams are barriers to mussels and their host fish.
Sand and gravel mining has been shown to cause catastrophic long-term damage of mussel habitats in several river systems in North America. However, there are areas within these channels, such as the portions with consistent flows near islands or constrictions in the channel, which may serve as refugia for riverine freshwater mussel and fish species.
The main-stem Allegheny River still maintains healthy populations of over 30 mussel species, however habitat disturbance and degradation have triggered the decline and loss of mussel communities in the navigational pools of the Allegheny River. The lower Allegheny system is thought to still have remaining populations of two federally endangered species, the clubshell (Pleurobema clava) and the northern riffleshell (Epioblasma torulosa rangiana), as well as a candidate species, rayed bean (Villosa fabalis). These systems may also contain two species that have been proposed for federal listing, rabbitsfoot (Quadrula cylindrica) and snuffbox (Epioblasma triquetra), as well as species that Pennsylvania considers rare or threatened, such as the threeridge (Amblema plicata) and round pigtoe (Pleurobema sintoxia).
WPC recently obtained a State Wildlife Grant (SWG) to survey the freshwater mussel populations in the navigational pools in the lower Allegheny River (pools 6, 7,8), to collect data on physical stream parameters (depth, flow, substrate composition), and conduct habitat mapping at our mussel study sites. Our research will expand our knowledge of the threats to these imperiled species, as well as species habitat preferences and spatial distributions. Ultimately, this information will lead to protection efforts for remaining viable freshwater mussel populations as well as restoration efforts for species lost from portions of their historic ranges.
Project timeline
July 1, 2005 - June 30, 2006
. Map in-stream macrohabitats in the lower portion of the Allegheny River (pools 6, 7 and 8)
. Compile GIS data layers to spatially characterize the Allegheny system
. Stratify stream and river reaches and identify sampling sites based on best available habitat for species of interest
. Determine sampling strategy
. Initiate freshwater mussel surveys in the Allegheny River using the Ohio River Protocol
. Initiate physical habitat characterizations for mussel sites in the Allegheny River
. Begin analyses of mussel and physical habitat data
. Develop written and/or oral presentations on preliminary work for stakeholders
July 1, 2006 - June 30, 2007
. Complete freshwater mussel surveys in the Allegheny River
. Complete physical habitat characterizations for mussel sites in the Allegheny River
. Analyze and compare mussel data
. Produce GIS maps of habitat and mussel distribution, mussel densities, species richness, recruitment estimates and viability in the study sections of the Allegheny River
. Complete analyses and produce a final report and associated GIS maps on health and protection of freshwater mussel of the Allegheny River, with specific attention to the protocol comparison study.
Expected Results
The proposed project will improve the knowledge of regionally and globally imperiled freshwater mussels. Many freshwater mussels in the Allegheny watershed are either federally endangered and/or species of concern in Pennsylvania. Our research will provide information that will aid in monitoring and restoration efforts for imperiled freshwater mussels in the Allegheny River watershed. Associated habitat information will benefit the public as well as resource managers from various agencies. For example, regulatory agencies can use information collected to revise commercial gravel dredging permits and to help establish protective buffers for these species. The PFBC placed freshwater mussels as a top priority fauna for conservation and will be able to use the comprehensive information gained from these surveys in developing conservation plans. The data will also allow for future restoration initiatives in providing a thorough snapshot of information on contemporary mussel populations. It will also provide demographic information necessary to establish population and community profiles for mussels in the lower Allegheny River.
Donation request!
WPC has been awarded a State Wildlife Grant to assess the freshwater mussels in the lower Allegheny River. But the research can't be done without a boat. WPC is seeking the donation or loan of a boat to make the project possible.
We are currently seeking:
. An 18-foot or larger boat. A preferable model would be open-hulled and capable of carrying 5 or 6 people. Small pontoon boats would be considered. A trailer is also desirable. If you have a boat in this size though, regardless of the specification just mentioned, give us a call.
. A pickup truck that can haul the boat. It should be a V6 or V8 engine and in good operating condition.
Contact Ryan Evans, Zoologist, at 412-586-2332 if you have a donation you would be interested in contributing.
Because WPC is a nonprofit charitable organization, the donor of the boat would be eligible to take a tax deduction. WPC reserves the right to reject offers of boats, vehicles, and equipment that are not suitable for our needs.