Enormous thanks to our 10 wonderful Watershed Council Volunteers who have helped us wrap up our 16th Annual Salmon Monitoring Season! We monitored four Island streams this year: Cooper Creek at the head of Eagle Harbor, 2 reaches on Springbrook Creek which flows into Fletcher Bay, Murden Creek which flows into Murden Cove, and Manzanita Creek which flows into Manzanita Bay (See our Salmon Monitoring Map).
Unfortunately, this was another low year for salmon returns and for sighting juvenile salmon on our streams. We recorded a total of 11 returning adult salmon, the vast majority coho, and just a handful of fingerlings (see figures).
As with the past few years, we are showing very low numbers of both returning adults and juvenile fish. These data are extremely concerning, and consistent with low area returns over the broader region. Salmon face a number of serious threats in Puget Sound, including overharvesting which can particularly hit small streams, loss of stream habitat for rearing young, and difficult conditions facing them in the open ocean due to large issues including climate change. Unfortunately, Bainbridge salmon are subject to the same risks that face the larger salmon populations throughout our region. Our data support an urgent need to do more work to protect, conserve, and restore salmon runs in Puget Sound and beyond.
We also for the first time this year witnessed the phenomenon of a few “bright” dead salmon, which are salmon that have not yet transitioned to their spawning colors that are found dead. In urbanized areas, bright salmon may be a sign of pre-spawn mortality that has been linked to urban stormwater runoff and more recently, specifically chemicals from vehicle tires. Although Bainbridge and our surrounding areas do not have the level of urbanization that we would expect to create large stormwater runoff issues in the same way that the Seattle and Tacoma areas do, we cannot rule out that stormwater runoff could be a growing issue for our area as well.
But among these difficult findings, we also had some wonderful experiences during monitoring. Our wildlife viewing included raccoons and otters, coyotes, and herons – see photo to left of a great blue heron enjoying a nice salmon lunch on Manzanita Creek!
We also had multiple sightings of a beautiful small riparian bird, the American Dipper.
Volunteers were able to alert the City to the need for additional sandbagging on the Springbrook weirs to maintain adequate flow this fall, and we are thrilled to report that the City has put this aging weir system on their Capital Improvement Projects list to pursue funds to replace and upgrade this salmon passage issue. Finally, we also identified a blockage downstream of Highway 305 on Murden Creek which looks like it will be addressed in the upcoming culvert replacement project by WSDOT in 2021. These are just the kinds of salmon passage improvements that we need to keep working on in order to improve habitat for our Island salmon, and we are hopeful that such improvements will contribute to the health of the salmon who call Bainbridge Island home.
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