At the request of agencies in Oregon and Washington hoping to protect endangered salmon, NOAA recently approved the removal of up to 60 sea lions near Bonneville Dam to reduce unnatural predation on salmon stocks as they pass through the dam’s fishway.  You can read more about the issue in a blog post I wrote a short while ago regarding this issue.   You can also read the full news story here.

From habitat projects to breeding and stocking programs, it appears that nothing short of removing dams will reverse declines in Pacific Salmon populations in the Northwest. At least that’s what most experts believe.

But removing predators could make a difference, albeit small. In addition to the many predatory birds that take advantage of the highly altered travelways of migrating salmon, sea lions stack up near fish ladders in places like Bonneville Dam on the Columbia River, eating all the salmon they can catch.

NOAA Fisheries Service recently recommended killing about 30 sea lions at the Dam, far fewer than Washington, Oregon and Idaho had hoped for, but it’s a start.

At least three runs of salmon passing through Bonneville Dam are threatened. Sea lions are not. But that pesky Marine Mammal Protection Act prevents states from doing anything about the sea lion problem without permission from the feds. And permission from the feds to do most things (as you may know) can take time.

I’m not saying that predators like sea lions are necessarily bad.  In fact, they play an important ecological role in their natural environment. But they’re chomping down on some very valuable salmon that we’re paying big money to save, under conditions far from ‘natural’ at the base of fish ladders.

Animal rights activists will no doubt pressure NOAA significantly, turning this into a huge issue likely requiring large amounts of red tape.

But on a positive note, sea lion control might actually make a difference. I for one hope that NOAA commits to this wholeheartedly and tries to make it work. Let’s do every reasonable thing within our power to give salmon a chance to recover.

The Wisconsin Department of Natural Resources is considering killing about 6,000 double crested cormorants  in Lake Michigan and on the shorelines of Green Bay, in order to reduce their predatory effect on sport fish. 

The DNR hasn’t officially announced the plan just yet, but it’s sure to receive tons of criticism from bird enthusiasts and animal rights folks, while garnering support from many anglers.  The plan would intend to cut the numbers of the once endangered birds to about half of their current level. 

Cormorants have recovered from low population levels all around the country, and are beginning to present a challenge to fishery managers in many areas.  For instance, cormorants are believed to be a significant cause of predation on Atlantic salmon in rivers in the northeastern U.S.

The issue of predator control has been a touchy one, however, which has made it difficult for fisheries managers to ‘get things done’ when they need to.  One could argue about the effectiveness about cormorant control, and I am personally unaware of the research behind this topic, but I certainly believe that experimental evaluation of these control projects is important in determining their effectiveness. 

The Wisconsin DNR cormorant program is sure to be controversial, but I certainly hope it goes through, and can be used as an additional learning tool to allow us to evaluate how effective these control efforts truly are, and if these efforts should be practiced in other situations.

Read the news story here