Tern terror

  • Caspian terns fill sky over Rice Island

    Masako Watanabe/The Daily Astorian
  OREGON

Near the mouth of the Columbia River in Oregon, Alfred Hitchcock's movie, The Birds, has come to life. Over 10,000 pairs of Caspian terns nest on Rice Island, and while the birds aren't attacking people, they are eating millions of young salmon (HCN, 10/26/98: Are birds to blame for vanishing salmon?).


A biological assessment of endangered salmon recommends that the Army Corps of Engineers relocate the birds. So starting April 1, two people will inhabit the colony's home on Rice Island, to scare the skittish terns away and steal their eggs. The Corps hopes that by playing mating calls on a nearby island, they can lure the birds there, where they'll be farther from juvenile salmon moving through the water.


Researchers worry that this solution could yield more problems.


"It's not clear where all these birds are going to go," says wildlife biologist Daniel Roby. "It's not clear that there's enough habitat or enough food to support all these terns if they were to nest on an alternative site. Until there are other colonies established, I think the conservation community is going to be very leery and anxious about eliminating the Rice Island colony."


Critics say that compared to other factors causing the decline of salmon, such as dams or climate change, terns are a minor problem.


"We don't want to divert energy, time and resources away from looking at the bigger issue of what kills salmon on these rivers, which are the dams," says LeeAnne Tryon of Save Our Wild Salmon.


Ironically, the Corps created Rice Island entirely from materials it had dredged from shipping channels on the Columbia River. Every year, it adds more sand to the manmade island - creating the perfect habitat for Caspian terns.