(c) Glen Tepke
|
Due to the remote habitat preferences of the Kittlitz's Murrelet, even the basics of this little seabird's life cycle are shrouded in mystery. Our understanding of its breeding habits is based upon very few observations; fewer than 30 nests have ever been found in North America, and only a handful of these have been observed closely. What is known, however, is that Kittlitz's Murrelets are decreasing at a startling pace.
Kittlitz's Murrelet is 9.5 inches in length, weighs 8 ounces and has a wingspan of 17". During the breeding season, the Kittlitz's Murrelet is a handsome bird, golden in hue, with white in the tail, and dark gray wings. Like all murrelets, the Kittlitz's is oblong in flight, with a plump middle and pointed head and tail. Its pale plumage and extremely short bill separate it from the similar-looking Marbled and Long-billed Murrelets. In winter, the Kittlitz's Murrelet takes on a stark black and white appearance. The bird's cap, nape, and back become dark gray, while the under-parts, sides, throat, and face become white; the thin, dark crown and white face separate it from similar murrelet species.
Within the United States, the Kittlitz's Murrelet is found only in Alaska, where its range is restricted to mountainous coastal areas in the southern and western parts of the state. In southeastern Alaska, this murrelet is most common around Glacier Bay. To the west, it is found across the southern Alaskan coast, and on several of the Aleutian Islands. It is more sporadic in western Alaska, found on islands of the Bering Sea, on the Seward Peninsula, and as far north as Cape Sabine. Kittlitz's Murrelets also breed on the Russian side of the Bering Sea, from the Sea of Okhotsk in the south, to the Chukchi Sea in the north. After breeding, the species leaves the protected bays on coastal waters for the sea, but where it actually winters remains a mystery. Small numbers have been reported in breaks in the pack ice.
A legend for the range map to the right can be found
here.
Kittlitz's Murrelets thrive in areas where tidewater glaciers meet the ocean. They nest at high elevations within glacial areas, on rocky scree slopes close to the coast. These murrelets feed in nutrient-rich glacial outflow areas along the coast. During the breeding season, the birds feed at sea around icebergs, or closer to the coast, often choosing fjords and bays that have remained relatively icy. As the breeding season winds down, Kittlitz's Murrelets move further out to sea, but details of the species' winter preferences are largely unknown.
Kittlitz's Murrelets dive for their prey, often in groups, or in the company of other species. While fish such as capelin, sandlance, and herring are preferred, the birds have also been observed feeding on macro-zooplankton and various invertebrates. Much remains to be learned about the species' dietary habits.
Knowledge about the Kittlitz's breeding habits is based on a mere handful of accounts. Even the species' exact breeding range is uncertain. The few documented nests have mostly been in unvegetated rocky areas around glaciers, or on cliff faces over the ocean.
Birds seem to arrive on the breeding grounds already paired. A single egg is laid in a scrape on the ground, often at the base of a large rock, presumably to protect it from potential rockslides. Based upon one observation, the incubation period is at least 24 days. The egg is variable in color, always spotted or splotchy, and well camouflaged. When the downy chick emerges, it too is similar in coloration to the rocky ground around it, and difficult to find even when its location is known. Chicks fledge at several weeks of age, often unbeknownst to the parents. Adult Kittlitz's Murrelets have been observed returning to the nest to feed their chick, only to find that it has departed for the ocean. Fledglings occasionally leave the nest before they can fly well, scrambling to the sea on foot. Once there, they quickly become powerful swimmers and divers, are able to feed themselves, and seem to have no further contact with the parents.
Most Kittlitz's Murrelets depart from the bays and fjords of their breeding grounds by late July. They disperse far and wide, but sometimes remain in certain areas until they are forced out by ice. There have been very few winter sightings, and where Kittlitz's Murrelets go in winter remains an ornithological mystery. Thawing waters in April and May herald a return to their breeding grounds.
Day, R. H., D. J. Kuletz, and D. A. Nigro. 1999. Kittlitz's Murrelet (
Brachyramphus brevirostris). In The Birds of North America, No. 435 (A. Poole and F. Gill, Eds.). The Birds of North America, Inc., Philadelphia, PA.
Kaufman, Kenn.
Lives of North American Birds. Houghton Mifflin Company, New York. 1996.
Sibley, David Allen.
The Sibley Guide to BirdsNew York. 2000.. Alfred A. Knopf,
U.S. Fish and Wildlife Service. 2002.
Kittlitz's Murrelet Candidate and listing priority assignment form..
Van Vliet, Gus. 1993. "Status Concerns for the "Global" Population of Kittlitz's Murrelet: Is the "Glacier" Murrelet Receding?" Pacific Seabird Group Bulletin. Vol. 20, No. 1.
