There have always been hundreds of sea lions in the Columbia River...hundreds, always...and this includes long, long before there were any dams.
They went all the way up to Celilo Falls...where just like at Bonneville, there were hundreds of sea lions and lots of salmon corked up trying to get past the falls.
The only thing that is different is that there is a remnant of fish compared to what was, and just like any other user group, the sea lions are fighting for their share of the crumbs...they're not doing anything different than they ever have, there just aren't hardly any fish left anymore...and that most certainly is not the fault of the sea lions.
Fish on...
Todd
I would not agree with your points.
California Sea Lions have never been threatened or reduced in historic populations....and then...
Sea Lions were protected by the MMPA and have increased their population by about 2 1/2 times. In the mean time the ocean has been harvested down including food fish such as herring and sardines.
Sea lions learn and adapt well. In the past 8 years since Bonneville has been reopened to Spring Chinook fishing the concentration of Sea Lions has increased big time. Same goes for the falls at Oregon City on the Willamette. 10 years ago it was rare to see sea lions near the falls. Now there are at least a dozen there every day.
And BTW, next time you hear someone tell you there is fossil evidence of sea lions as far up as Celilo, remember that was an inland sea when those fossils were formed.