As two culverts are replaced to improve fish passage in Crystal Springs Creek (Westmoreland Park, Portland, Ore.), 25 citizen-scientist volunteers and watershed specialists gathered to rescue freshwater mussels and relocate them upstream, out of the project area and out of harm’s way.
Members of the Crystal Springs Partnership with guidance from the Xerces Society prepared to retrieve, measure, tag, and relocate some 2000 freshwater mussels found in the creek. At a similar relocation event in 2013, some of the same volunteers rescued mussels from a different reach of Crystal Springs Creek, and were equally surprised at the abundance of mussels in the Creek.
The existence of mussels in Crystal Springs Creek is a testament to the relatively cool, clean water. Mussels do not possess legs, wings, or other appendages. Their movement is dependent on fish, including coho salmon, prickly sculpin, and threespine stickleback, who serve as hosts, carrying larval mussels attached to their gills as the fish move through the watershed. As a result of this symbiotic relationship, we have evidence of the movement of both native fish and mussels in the watershed.
So why help these mussels cross the road? Freshwater mussels are experiencing a dramatic decline; seventy-one percent of all species of North American freshwater mussels are considered endangered, threatened, or of special concern, representing one of the most at-risk groups of animals in the United States.
Native freshwater mussels have immense ecological and cultural significance. As filter-feeders, they can substantially improve water quality, which benefits aquatic ecosystems and, ultimately, humans. Highly sensitive to environmental changes, these animals can be used to assess water quality. Freshwater mussels were historically important sources of food, tools, and other implements for many Native American tribes. Native Americans in the interior Columbia Basin have harvested these animals for at least 10,000 years.
Further support for this effort was provided by Oregon Department of Fish and Wildlife, USFWS and City of Portland Bureau of Environmental Services and Parks and Recreation staff. This project was made possible with funding from the Oregon Watershed Enhancement Board
**UPDATE: Since this collection event, further action has raised the total number of rescued mussels to 3,432!**