Every year, vast numbers of salmon return from the open ocean to spawn. Their remarkable journey takes them up roaring rivers, past man-made dams, and through the claws of waiting predators until, finally, they reach their ancestral spawning grounds where they mate and die. These annual runs are essential both for the health of local ecosystems and for commercial fisheries, but plummeting salmon populations have cast their future in doubt and have lead to a multi-billion dollar recovery effort. One controversial aspect of that effort, however, has pitted animal-rights advocates against officials: the culling of hungry sea lions who gather to feed on migrating salmon.

 

The Columbia River in America's Pacific Northwest has historically been home to one of the largest runs of coho, steelhead and rare chinook salmon in the world. Over the past century, fourteen dams have been built on the river, slowing the currents and creating significant obstacles for migrating fish. The declining health of the oceans and decades of overfishing have also decimated the population, leading to smaller runs and periodic moratoria on harvests.

 

This year, however, improved ocean conditions are expected to yield one of the largest runs in recent history. As the salmon swarm upstream they collect at the base of the dams, waiting for the opportunity to climb fish ladders, modified stretches of river which allow them to circumvent the dams or other obstacles. But salmon aren't the only ones gathering. Sea lions, which depend on fish as a staple of their diet, have learned that these dams represent a smorgasbord and are taking advantage of the sudden bounty.

 

The sea lions, which can weigh 600 pounds or more, are eating too many fish, officials say, leading to a policy of capture and culling for those individuals which cannot be discouraged by hazing with rubber bullets and loud noises. Sixty-three animals are currently being tracked as "repeat offenders," the most incorrigible of which face a bleak future.

 

Animal rights advocates claim this policy is flawed and that sea lions are being killed for simply doing what nature intended them to do. Dams, commercial fisheries and mismanagement of the river's watershed lead to far more salmon deaths than sea lions do, they say.

 

Wildlife officials counter that every effort must be made to save the spawning salmon and promise to keep the number of sea lions killed to an absolute minimum. In 2009, eleven animals were killed and four others were transported to zoos. Attempts will again be made this year to relocate some offenders to zoos or aquariums across the country.

 

The question of ecosystem management and restoration is a problematic one, especially in areas where economies depend heavily upon natural resources. Hopefully, future generations will find ways to restore the natural paths of the rivers, to restore the health of the watersheds upon which the fish depend, and to alleviate the need for artificial management of the populations — both predator and prey.