Streamers could save birds from hooks

Fluttering streamers could save seabirds from fatal encounters with many longline

The short-tailed albatross. Rob Shallenberger

Seabirds that are sometimes snagged by hooks could be saved by streamers trailing from a fishing boat. Melvin

fishing boats, according to a big study.

The streamers could also save part of the U.S. fishing fleet from the financial

consequences of accidentally killing endangered species, says Ed Melvin of the

federally funded Washington Sea Grant Program in Seattle. Short-tailed albatrosses

are so rare that if the entire fishing fleet in the Bering Sea and the Gulf of

Alaska catches as few as two on longline hooks in 2 years, the Endangered Species

Act will kick in and require more protection for the birds.

The study focused on demersal longline fishing boats, which trail lines of baited

hooks to the depths of such species as cod and halibut. Birds crowd around to

snatch waste but sometimes lunge for the hooks. U.S. regulators already require

some kind of warning object above the hooks. Before tightening regulations,

however, they sought data on what really works.

After 2 years of testing bird-protection devices, Melvin and his colleagues report

that streamers dancing from two strings suspended behind the boat can keep

seabirds away from the hooks as they sink off the boat’s stern. The project’s

formal report is still in review, but Melvin offered a preview at the American

Ornithologists’ Union meeting in Seattle last week. In on-water tests, the

streamer system cut the accidental deaths of seabirds by 94 percent, he said.

Thorn Smith of the North Pacific Longline Association in Seattle praises the study

for including the fishing industry, as well as regulatory agencies. Wide input

proved “absolutely essential,” says coinvestigator Julia K. Parrish of the

University of Washington in Seattle. Usually, “that step . . . is sadly lacking in

conservation,” she says.

Smith urged the researchers to seek more realistic results by doing their tests on

commercial fishing vessels during normal operations rather than vessels chartered

specifically for research. Also, the 2-year study gauged the devices’

effectiveness over a period that reflects the natural variability in seabird

numbers.

The testers sighted the endangered short-tailed albatross a few times, but never

saw one hooked. Most of the world’s remaining 1,500 of these birds breed on the

active volcano of Japan’s Torishima island, but they forage widely. “When a bird

gets that endangered, every one counts,” explains endangered species biologist

Greg Balogh of the U.S. Fish and Wildlife Service in Anchorage.

The streamer setup “is one of the cheapest alternatives we have,” he says. Parrish

estimates that perhaps $150 would outfit a boat. Regulations may eventually

require them on U.S. vessels. Parrish says she dreams that some philanthropist

will one day buy devices for boats around the world.

Susan Milius is the life sciences writer, covering organismal biology and evolution, and has a special passion for plants, fungi and invertebrates. She studied biology and English literature.

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