Glacier Murrelet Driven towards Extinction by Global Warming?

On May 10, 2001 the Center, joined by the Coastal Coalition, Eyak Preservation Council, Lynn Canal Conservation, Inc. and the Sitka Conservation Society formally petitioned the U.S. Fish & Wildlife Service to list the Kittlitz's murrelet as an Endangered Species under the federal Endangered Species Act. The petition also requests that critical habitat be designated for the species.

Documented Population Collapse

The Kittlitz's murrelet, Brachyramphus brevirostris, is a small diving seabird in the Alcid (Auk) family which breeds only in certain sections of coastal Alaska and to a limited extent in the Russian Far East. The largest known populations occur in Southeast and Southcoastal Alaska, where dramatic population declines have been observed over the past decade or so. In Prince William Sound, data show an average 14.5% annual decline between 1989 and 1998. Recent surveys also suggest a decline of 80% in Glacier Bay between 1991 and 1999. The current worldwide population likely numbers approximately 10,000 individuals, a dramatic decline from the several hundred thousand estimated to occur in the Gulf of Alaska alone in 1972.

The Glacier Murrelet

The Kittlitz's murrelet is sometimes referred to as the "Glacier Murrelet" because in the summer it forages almost exclusively at the face of tidewater glaciers or near the outflow of glacier streams, and nests in alpine areas in bare patches among the ice and snow. This intimate association with glaciers is unique among seabirds. The Kittlitz's murrelet is related to the marbled murrelet, and overlaps considerably with this species in range. However, the Kittlitz's murrelet is differentiated from the marbled murrelet by its highly specific glacial-affected habitat requirements.

Isleib and Kessel (1973) reported a flock of 10,000 Kittlitz's murrelets in the upper half of Unakwik Inlet on 30 July, 1972. Today, the worldwide population may number less than 10,000, and recent estimates for Unakwik Inlet suggest that less than 100 birds remain there.*

Isleib and Kessel (1973) reported a flock of 10,000 Kittlitz's murrelets in the upper half of Unakwik Inlet on 30 July, 1972. Today, the worldwide population may number less than 10,000, and recent estimates for Unakwik Inlet suggest that less than 100 birds remain there.*

Relatively little is known about this rare and mysterious species. Its winter range, for example, is almost entirely unknown. The Kittlitz's murrelet nests high in rugged coastal mountains, where females lay one egg in little more than a scrape or depression in bare spots among the snow and ice. The diet of the Kittlitz's murrelet consists of forage fish and macrozooplankton.

Threatened by Global Warming and Reduced Prey Availability

The Kittlitz's murrelet's breeding and foraging habitat is disappearing. Global warming is happening even faster in Alaska than in more temperate regions. Average temperatures in the range of the Kittlitz's murrelet have risen 5 F (3 C) since the 1960s and 8 F (4.5 C) in the winter.

In addition to this overall warming trend, the Gulf of Alaska underwent a cyclical regime shift in 1976-1977 from a cold to a warm regime. The warming of ocean temperatures due to this shift has been linked to the decline of the Kittlitz's murrelet forage fish prey such as capelin, herring, and sandlance.

Threatened by Marine Oil Pollution, Vessel Traffic and other Human Activities

The Kittlitz's murrelet appears to have been substantially impacted by the 1989 T/V Exxon Valdez oil spill. There is evidence that the species suffered a larger proportionate loss of its population than any other species in the spill. There is little evidence that the Kittlitz's murrelet has since recovered from the spill in Prince William Sound. The risk of catastrophic oil spills has not been adequately reduced within the range of the Kittlitz's murrelet since the T/V Exxon Valdez oil spill. If anything, the risk of another spill has probably increased.

There is also evidence that chronic disturbance from vessel traffic in glacial fiords (in particular large cruise ships) can cause Kittlitz's murrelets to abandon feeding areas. Impacts from vessel traffic may include the scattering of the Kittlitz's murrelet's forage fish prey, and disturbance from the underwater noise generated by the vessels.

Kittlitz's murrelets are also sometimes caught in near shore gill-net fisheries, when these fisheries overlap with Kittlitz's murrelet congregations. The petition calls for increased observer coverage of the near shore gill-net fisheries in order to document the actual extent of Kittlitz's murrelet bycatch.

Documented Recruitment Failure

A near total lack of recruitment has been documented in one recent study in Prince William Sound. Recruitment failures are also suspected in Glacier Bay, one of the species' historic strongholds. The precise cause of the Kittlitz's murrelet's inability to produce chicks that survive and mature is unknown. It is likely related to one or more of the above threats.

The Kittlitz's murrelet warrants immediate listing under the Endangered Species Act.

* Meares Glacier, AK Unakwik Inlet, Chugach; Thomp/Port US Navy Photo July 31, 1957. Photograph from the American Geographic Society Collection archived at the National Snow and Ice Data Center, University of Colorado at Boulder and obtained from the Internet at
graphic Andrew Rodman ©2002
February 15, 2005
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