AN INNOVATIVE TRACKING system used in the Northwest came to some surprising discoveries while tracking juvenile salmon migrating downstream to the Pacific Ocean. Scientists learned that just as many salmon or more survived going over eight dams on the Northwest's Snake and Columbia Rivers as others did going down a major river in British Columbia without any dams at all.
The study was published in the online edition of the Public Library of Science Biology and it arrives just when salmon advocates are in a battle in federal court with the Bush administration and dam advocates over whether the Columbia Basin dam system can be made safe enough for salmon to satisfy regulations under the Endangered Species Act.
What the study suggests is that there's a chance salmon can survive going over dams as easily as traveling down rivers that do not have dams.
The tracking system used is called the Pacific Ocean Shelf Tracking, where fish were implanted with an acoustic transmitter about the size of an almond.
It sends out a signal tracked by many receivers in the rivers and ocean. Also, salmon were monitored with Passive Integrated Transponder tags to see their survival rate over dams. This testing, however, was limited to juvenile salmon.
This discovery should act as a springboard to conduct studies in California, where a complete collapse of the salmon population nearly shut down salmon fishing
NOAA Fisheries, the federal agency in charge of restoring threatened and endangered salmon, has asked POST developer David Welch to monitor salmon in the Sacramento River. We hope he takes the offer.
While the study was limited to juvenile salmon, an expansion of POST examination of state rivers and dams could be the start of improving dwindling salmon runs and help the fishing industry in the future.