Landscape drivers of freshwater mussel assemblages and imperiled species status: implications for optimal allocation of conservation effort within the Delaware River Basin
September 2021 - May 2023
- U.S. Geological Survey
The Delaware River provides an ideal case study for developing a basin-wide conservation strategy for imperiled freshwater mussels in the North Atlantic-Appalachian Region. The watershed contains 12 species of Atlantic slope mussels (Blakeslee et al. 2018), including the federally endangered Dwarf Wedgemussel and the at-risk Brook Floater. Nearly 15 million people depend on its water supply, and propagation of freshwater mussels is actively being pursued by conservation groups to aid water quality improvements in the estuary. The variation in dominant stressors throughout the basin, from environmental flow issues in the upper basin to water quality issues and saltwater intrusion in the lower basin, coincide with documented shifts in mussel community composition (Blakeslee et al. 2018). These complexities require a deliberative and transparent process to identify robust and collaborative conservation strategies. Our research activities will help foster a basin-wide perspective on mussel conservation and identify collaborative strategies for implementation by federal, state, and non-governmental groups working in the Delaware. The approach to assessing threats and prioritizing actions will be transferable to other watersheds with similar mussel assemblages.
The overarching goal of this project is to develop a framework to inform decisions on the allocation of conservation effort across potential actions and watersheds to advance freshwater mussel conservation in the Delaware River Basin. This will be achieved through a structured decision-making process to identify robust conservation strategies, combined with predictive modeling of existing data to understand the local and landscape stressors affecting mussel community resilience throughout the basin. Specifically, this project seeks to:
1. Identify portfolios of freshwater mussel conservation actions based on national recommendations, locally identified objectives, and feasibility
2. Develop predictive models of the stressors and conservation efforts affecting freshwater mussel resilience and community structure
3. Integrate multi-attribute tradeoff analysis with empirical models to inform spatial application of freshwater mussel conservation actions