Kittlitz's Murrelet a Candidate for Endangered Listing

WASHINGTON, DC, May 5, 2004 (ENS) - The U.S. Fish and Wildlife Service has named an Alaskan seabird known as the Kittlitz’s murrelet as a candidate for protection under the Endangered Species Act. The Service periodically publishes an updated Candidate Notice of Review to solicit new information on the status of candidate species and the threats to their survival.

The Kittlitz’s murrelet was designated as a candidate species because its numbers have declined sharply and it may warrant listing as threatened or endangered under the Endangered Species Act. Candidate species are not subject to the regulatory protections of the Endangered Species Act, and human activities that may affect candidate species are not restricted, the Service said.

Candidate status signals that there are conservation concerns about a species, and the Service encourages agencies, organizations and individuals to participate in research and conservation activities that may preclude the need to list the species. The Service will prepare a proposal to list the Kittlitz’s murrelet when funding becomes available.

(Photo courtesy )

The Service says that Kittlitz‘s murrelets in Prince William Sound have declined by 84 percent since 1989, and could disappear from the region in 30 years. In 1989, the Exxon Valdez ran aground in the Sound spilling some 11 million gallons of oil.

Recent declines in the Glacier Bay population center would, if continued, wipe out that population of birds in about 40 years, the Service said.

Data from the Malaspina Forelands suggests that its local population of Kittlitz’s murrelets declined by at least 38 percent, and perhaps by as much as 75 percent, between 1992 and 2002.

In the Kenai Fjords area, it is estimated that the murrelet population has declined by as much as 83 percent since 1976.

Because Kittlitz’s murrelets tend to forage in glacially-fed waters during the breeding season, scientists are speculating that the decline in Kittlitz’s murrelets is related to the retreat of tidewater glaciers.

Most glaciers in Alaska, including many of those surrounding Glacier Bay and Prince William Sound, have been receding since the turn of the century. Exactly how glacier retreat might affect murrelets is unknown.

Studies in other regions have recorded low biological productivity in fjords with receding glaciers, as a result of increased sedimentation and lowered salinity. These factors could result in fewer forage fish for the murrelets, while the sedimentation might reduce the birds’ ability to see and catch prey.

"These are all untested hypotheses, of course, and we must continue to obtain basic information about Kittlitz’s murrelet habitat, foraging behavior, and food requirements to increase our understanding of these birds and improve our ability to determine the reasons for their population decline," the Service said.

In addition to the global climate impacts on fjord habitats, Kittlitz’s murrelets may have also been affected by changes in their available prey species, due to changes in the marine environment. Lack of food has led to poor reproduction for this murrelet.

It is also possible that the breeding birds are disturbed by marine vessel traffic, or by helicopter flights over their mountain-scree nesting areas. Primary breeding areas for Kittlitz’s murrelets - the Kenai Fjords, Prince William Sound, and Glacier Bay - are all experiencing increases in tour operations. The preferred habitats of Kittlitz’s, near tidewater glaciers, are also prime destinations for tour and cruise ships, increasing the potential for disturbance.

At least two sources of human-caused mortality for Kittlitz’s murrelets have been identified, although their impacts on the total population are not known.

These include gillnet fisheries and oil spills. Being small-bodied, near-shore divers, these birds sometimes get caught in gillnets and drown. The same traits make them susceptible to oil spills - both catastrophic spills such as the 1989 Prince William Sound disaster and smaller but more frequent spills resulting from small vessel sinkings.