For Beleaguered Salmon, Every Day Is A Tern-Down Day

Caspian terns are feasting on young salmon as the fish ride the Columbia River on their way to the ocean. You might ask, “What’s the big deal? Some birds eat fish.”

But this is a big deal. The Caspian terns are disrupting an immense recovery and planning effort focused on rescuing some salmon runs from extinction and ensuring the continued abundance of others. The terns represent one of many tests our regional effort will have to overcome in order to achieve success.

These are not just any birds and they aren’t eating just any fish. The salmon are the product of an intense regional salmon recovery program valued at as much as $435 million annually for the Columbia-Snake river basin.

While this program produces significant numbers of hatchery fish, it has been unable to arrest the decline in wild salmon. It is the wild fish that have fallen to precarious levels. Some of the wild fish coming from the Snake River and its tributaries have been on the endangered species list since 1992, while others coming from the upper, middle and lower Columbia were listed for protection just this year. Only 300 wild adult fall chinook and two sockeye salmon made it past Lower Granite Dam in 1998, the uppermost Snake River dam with fish passage.

The tern problem was discovered last year when a large number of tiny electronic tags the size of a grain of rice started showing up in bird droppings on Rice Island, a small pile of sand and rock near Astoria, Ore., in the lower Columbia River. These PIT tags had been inserted in young salmon to track their journey down the river and through the dams. Red flags were raised by the unusual number of PIT tags that were found and the scientific estimates that Rice Island terns were consuming 6 to 25 percent of all salmon coming down the river.

There are certain facts that any plan to remedy this situation must take into account. The island is in an ideal place for salmon-eating birds because it is located where freshwater and saltwater meet. At this point in the river, salmon are more likely to linger and surface - which is fine if you are a hungry tern.

The birds were also not unwanted on the island, initially managed as tern habitat by the U.S. Fish and Wildlife Service and the Army Corps of Engineers. The colony thrived, growing to 20,000 birds, the largest tern colony in North America.

Also, the island itself is the creation of the Corps of Engineers, which built it with the byproduct from dredging the Columbia River for shipping.

Finally, while the terns are not an endangered species, they are accorded some protection by the International Migratory Bird Treaty Act.

Initial efforts to resolve the tern problem have highlighted some inherent difficulties. Winter wheat planted on the island to deter nesting failed to grow adequately. Makeshift fencing discouraged nesting but caused the terns to crowd onto a one-acre plot set aside for a small, fail-safe population. Where there were only supposed to be 2,000 terns, there are now more than three times that number and only about 1,100 terns ventured over to an island targeted for their relocation. One of the few things that did work as planned was the tern decoys. Some terns, in fact, were observed offering food to decoys as part of a mating ritual. Unfortunately, the food was often young salmon - which even the relocated terns continue to favor.

As the Northwest struggles to prevent salmon extinction, we have an opportunity to demonstrate our resolve by solving the tern problem. We must reduce the impact of terns to a level that predated the creation of Rice Island.

Terns on Rice Island are important, not because they are the only problem facing salmon - far from it - but because they are disrupting a multimillion-dollar investment in salmon recovery that has other issues to face, many of them more contentious.

This is not to diminish the complexity of the tern problem, however. To be effective, our response must emphasize the fundamentals of effective planning - clear goals, good science, public involvement, effective implementation, careful evaluation, adaptive management, and most of all, clear accountability.

As this year’s attempt appears to fall short, we must redouble our efforts, incorporating what we have learned about tern behavior and moving decisively to solve this problem.