Salmon study nets a big wow
June 9, 2008 · Updated 5:45 PM
The city-led effort finds that young fish arent behaving like anyone believed.
Nets cast from the islands shore have drawn a startling catch.
Besides capturing, cataloging and releasing almost 60 species of sea life, a city-led study has netted data that shows Puget Sound salmon arent behaving as many expect suggesting that government protections are falling short for the most sensitive salmon species.
Its all a big wow, said island resident and marine habitat specialist Jim Brennan. This is new information. Were seeing that salmon are not doing what we thought and that the regulations there to protect them are not really protecting them.
In a joint effort by the City of Bainbridge Island, the Suquamish Tribe and the state Department of Fish and Wildlife, a corps of volunteers logged over a thousand hours casting more than 150 nets along the islands shore between 2002 and 2004.
The beach seining project was meant to gather a simple baseline of raw data. But the recently compiled results surprised city shoreline planner and project lead Peter Namtvedt Best.
This was to just answer some basic questions because we dont really have a good idea of how many or what kinds of critters are out there, he said. But what weve heard about chinook and other salmon is not what were learning from this study.
Even salmon are flocking to Bainbridge Island for the the quiet life.
Nets drawn from the islands shore during the beach seining study found that numerous salmon from Northwest hatcheries are bucking the assumption that young salmon leave streams and make a beeline for the ocean. Many salmon are hanging out off the islands shores for much longer than expected.
Theres the book of thought that says salmon take a right and head out to the ocean, Best said. But these salmon didnt read that book. Salmon are coming down here from all over the place.
Because hatchery salmon are tagged, Best and other study participants were able to trace the origins of many chinook and coho caught in nets off Bainbridge. Typically released from river-based farms, fish were thought to spend about 18 days in Puget Sound before plunging into the Pacific.
But some of the these salmon we found had been in the sound for 165 days, Best said. And that raises some interesting questions.
Best guesses that the salmon could be seeking the more readily available food and protected environments common on off-shore habitats. It could also mean salmon are having a tougher time thriving in the ocean.
Do fish exhibit preferences and actively search for certain habitats, food resources and geographical areas or are they just milling about, flowing with the currents and opportunistically eating whatever they come across? he asked.
Marine habitat specialist Jim Brennan doesnt know the answer for sure, but said salmon are also hanging out longer in other parts of the sound, including Vashon Island and south Snohomish County.
Its a big jigsaw puzzle and this is another piece, he said. I dont know why theyre doing this, but it does mean they are subject to the affects of all that we do to the sound for a longer period of time. They are subject to our water quality, habitats, food supply a lot longer and this could affect their ability to thrive.
The young salmon off the Bainbridge coast are also rushing to the island with remarkable speed, Best said. At least one young salmon released from British Columbia hatcheries reached the islands waters in a matter of days, he said.
Brennan said studies he conducted for King County found similar results, with young salmon traveling nearly an equal distance to reach Vashon.
Were talking about small fish, the size of your finger, Best said. How is it physically possible to travel that distance in a matter of days?
Best and Brennan surmise the salmon could be hitching rides on fast currents that zip them through 80 miles of Puget Sound water in a couple days.
The results also beg the question of whether this odd travel itinerary is widespread in wild salmon.
There is the often-stated question of whether wild and hatchery behave the same, Best said. The only (hatchery) species that are tagged are coho and chinook, so its hard to know about other species, but its reasonable to think there is some behavior difference.