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Alaskan birds in jeopardyDecember 3, 2007Courtesy of Far North Science 
Kittlitz's murrelet The little-known Kittlitz's murrelet - a species so elusive that scientists didn't record its croaking call for the first time until a few years ago - has crashed by more than 80 percent since the 1970s throughout its icy range rimming the Gulf of Alaska. The birds, genetic cousins to puffins and murres, spend summers diving for food in the meltwater rivers that flush from glacial faces, while nesting in the mountains on the ground. Almost nothing is known about their ecology and life cycle - only a few dozen nesting sites have ever been documented and no one really knows much about where the birds spend winters. Yet the shrinkage of glaciers, and the rapid increase in freshwater at glacial faces, appears to have decimated the bird's food sources or made it much more difficult to snatch eats. Example: Something like 63,000 murrelets were thought to summer in Prince William Sound in the 1970s. By 2000, the number had dropped to an estimated 1,000. Listen to the Kittlitz's murrelet Watchlist technical report (PDF) It's possible that the world population of the murrelets is now as low as 7,000, according to 2004 estimates. "The fate of the Kittlitz's murrelet likely hinges on the fate of Alaska's glaciers, and therefore may be among the world's first avian species to succumb to effects of rising global temperatures," wrote federal biologists John Piatt and Kathy Kuletz in a 2004 scientific paper. They called it "Alaska's avian 'poster child' for global climate change." The WatchList 2007 - a new study by Audubon and the America Bird Conservancy - worked over avian research, data from the Christmas Bird Count and the annual Breeding Bird Surveys, to pinpoint 178 species in the continental states and 39 species in Hawaii that need conservation aid fast. A release by Audubon called the report "a call to action to save species fighting for survival amid a convergence of environmental challenges, including habitat loss, invasive species and global warming." These 217 species aren't the only avian critters in trouble. Audubon has also been tracking a disturbing decline in 20 common species, via four decades of data compiled during Christmas Bird Counts and Breeding Bird Surveys: Since 1967 the average population for the common birds in steepest decline has fallen 68 percent, from 17.6 million to 5.35 million. Some species have nose-dived as much as 80 percent and all 20 birds included in the Common Birds in Decline report have lost at least 50 percent of their population - in just four decades. A story about the Alaskan species on the watchlist by Anchorage Daily News's Erika Bolstad puts the threats in perspective:
Kittlitz's murrelet The Audubon watch list, last updated in 2002, is a compilation of the most imperiled bird species in the United States. Twelve Alaska birds make the most critical "red" list, compiled by Audubon and the American Bird Conservancy. Another 36 are on the yellow list, a category that designates them as needing what Audubon terms "urgent conservation action." The national watch list includes well-known species on the endangered species list, such as the spotted owl, the California condor and the whooping crane. But it also includes lesser-known coastal birds that are threatened with extinction, such as the Kittlitz's murrelet, which has seen its situation worsen since the 2002 list was released. The data are compiled from state, federal and academic studies as well as Audubon's annual Christmas bird count. "To save Kittlitz's murrelet, we need to halt global warming," said Greg Butcher, director of bird conservation for the National Audubon Society, told Erika Bolstad of the Anchorage Daily News in this story. "That's the only way we're going to have total success." Here's an excerpt from a story I wrote about the species in 2004: "The fate of the Kittlitz's murrelet likely hinges on the fate of Alaska's glaciers, and therefore may be among the world's first avian species to succumb to effects of rising global temperatures," Piatt and Kuletz, wrote in the abstract to a report to the 2004 Alaska Bird Conference. No one knows yet how retreating glaciers harm the birds, Kuletz added in another report. The birds can be found off remnant glaciers in the Aleutians, and small populations still exist at the tip of the Seward Peninsula and along the coast of eastern Russia. But studies from other areas have found a clue. The vast amount of fresh water and silt flushing from a receding glacier can reduce the amount of food in a fjord, Kuletz said. For a hungry murrelet, this might be very bad news. Not only are there fewer fish, but they're also harder to see. These ideas must be investigated further, she concluded. Little is known about the bird's life cycle. Its territory overlaps with the marbled murrelet, which nests atop old-growth trees. But the glacier murrelet is much harder to study, said Piatt, a research biologist with the U.S. Geological Survey in Anchorage. It nests in bare rocky slopes high in the mountains up to 40 miles from the ocean. With grayish coloring, it is hard to see on land or sea. Kittlitz's murrelet in winter Source: USGS "Their ecology is so obscure, and they don't give up their secrets easily," Piatt said. "There's only been 23 nests found. Ever. All of those were found accidently by people hiking. So we know almost nothing about their breeding biology." Until a few years ago, no one had even recorded their strange croaking call, Piatt said. Additional studies will focus on population trends in the Aleutians and Glacier Bay and other areas, while trying to find out more about what they eat and the effect of glacial retreat.
The birds summer in Harriman and College fjords as well as Blackstone Bay, 20 to 50 miles by boat outside of Whittier, Piatt said. "On the small scale, people should be sensitive to these birds," Piatt said. 
Most of Far North Science is written and edited by Doug O'Harra, a writer and journalist based in Anchorage, Alaska. |
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