Taking a close look at a seabird colony

Southeast wild

Posted: Friday, March 17, 2000

One of the largest seabird colonies in Southeast Alaska is found on a tiny volcanic island at the mouth of Sitka Sound.

St. Lazaria Island, about 15 miles from Sitka, is a nesting site for hundreds of thousands of seabirds. Fork-tailed and Leach's storm-petrels make up the largest population on St. Lazaria, with a quarter-million breeding pairs between them.

Just six-tenths of a mile long and 400 yards wide at its widest point, it supports large populations of seabirds in part because it has few predators and abundant food awaits in the surrounding waters.

St. Lazaria is just one link in the 4.5 million acre Alaska Maritime National Wildlife Refuge made up of more than 2,400 islands, headlands, rocks, islets, spires and reefs along the Alaska coast. The refuge stretches from Cape Lisburne on the Chukchi Sea to the tip of the Aleutians and eastward to Forrester Island on the border of British Columbia.

Since 1993, wildlife biologist Leslie Slater of Homer has overseen summer-long research on St. Lazaria. Around Memorial Day Leslie, an assistant and two volunteers will board a landing craft in Sitka to gain access to the rugged outcropping around mid-tide. Until Labor Day they will operate out of a primitive administrative cabin, catch drinking water from the roof and spend their days on the ground, reaching into burrows to check eggs and chicks. They'll also circumnavigate the island by rubber skiff to count seabirds from the water.

They are collecting baseline data on nine species. The idea of the program, says Slater, is to sample the same species over a broad area to monitor health of the total marine environment, including their prey. Annual studies are conducted at nine refuge sites located about 500 miles apart.

In addition to the petrels, they are studying Pelagic Cormorant, Glaucuous-winged Gull, Pigeon Guillemot, Common Murre, Thick-billed Murre, Tufted Puffin and Rhinoceros Auklet.

In the summer of 1998 they documented the first sighting of Cassin's Auklet on St. Lazaria. Sightings the following summer as well suggest the species may be extending its range northward from Lowrie Island near the southern border of Southeast Alaska and the Queen Charlotte Islands where they are abundant.

The past seven years' research on Lazaria have not shown startling changes, Slater says. But the goal is long-term collection of data. If research like this had been in place in Prince William Sound prior to the Exxon Valdez oil spill, effects of the spill would have been more measurable, she says.

Part of their work is collection of eggs for analysis. They also walk beaches looking for oil. To date they have not documented evidence of pollution, she says. And they haven't studied St. Lazaria long enough to know how warmer ocean waters may be impacting the sea birds. Severe weather clearly affects survival of eggs and chicks, either through damaging nest sites or preventing parents from returning to the nest. This summer for the first time a refuge research vessel from Homer will travel to St. Lazaria to sample availability of prey for the birds.

Visitation on St. Lazaria is not encouraged because of its importance to seabirds, and Slater acknowledges their crew's presence also has a negative impact. To minimize damage, she and her team do not allow themselves to stray from established trails. Wherever there is soil, it will be used by birds. Storm petrel burrows may be as dense as four per square meter.

The trails they use were probably created during World War II. A concrete pad for a small shed and rusting remains of a winch testify to its use as a military outlook site.

The best way to visit St. Lazaria is offshore, by boat. June is the noisiest month, when petrels return to burrows at night with high-pitched twitters, hoots and trills. Watching them move in and out is like watching slow-moving bats, says Slater. Storm petrels locate their own burrow by use of scent.

If she were to describe the scent of Lazaria, Slater says it would be the smell of petrels - an oily, musky, sweet scent.

Their work location is both remote and close to human activity. A cell phone provides a safety link. On a clear night the 4th of July fireworks are visible from Sitka. They manage a trip into town once a month for supplies and a shower. Friends in the charter boat business deliver mail and produce. Waters around Lazaria are busy with boat traffic during July and August.

About 75 percent of Alaska's marine birds (15 to 30 million birds among 55 species) use the Alaska Maritime Refuge. Each species has a specialized nesting site (rock ledge, crevice, boulder rubble, pinnacle, or burrow) - an adaptation that allows many birds to use a small area of land. The refuge has the most diverse wildlife species of all the refuges in Alaska including thousands of sea lions, seals, walrus and sea otters.

The Juneau Audubon Society adopted the Gulf of Alaska unit of the Alaska Maritime National Wildlife Refuge several years ago and maintains an ongoing interest in its future.

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