Marbled Murrelet in a freefall
Forest-nesting seabird’s population down almost 30 percent in northwest states
Published: February 15, 2013
 Marbled Murrelet
Photo by U.S. Fish and Wildlife Service In 1997, five years after the U.S. Fish and Wildlife Service listed Marbled Murrelet as Threatened under the Endangered Species Act due in part to decades of population decline, an agency report predicted the species would continue to shrink at a rate of 4 to 7 percent per year.
That prediction has been borne out. According to a paper published in November 2012 in the journal The Condor, populations of the seabird south of Canada dropped 3.7 percent per year from 2001 to 2010, amounting to a decade-long freefall of 29 percent.
The period’s high count, in 2002, totaled 23,700 birds; by 2010, the total stood at 16,700.
The plunge was most severe in Puget Sound and along the coast of Washington, where numbers fell 6.5 to 7.4 percent per year, or as much as 46 percent over the 10 years.
Marbled Murrelet is a 10-inch-long seabird that spends the winter along the Pacific Coast from Alaska to California. When it’s time to breed, it shuns the ocean and flies inland to nest 40 feet high in large trees in old-growth forests.
While nesting, murrelets regularly return to the ocean to feed, offering scientists their best opportunity to count them. Researchers from the U.S. Forest Service, the U.S. Fish and Wildlife Service, the Washington Department Fish and Wildlife, and a private research firm sailed boats along predetermined transects off the coasts and tallied all the murrelets they found.
The scientists say they were not surprised that they counted fewer birds each year, since it’s still too early for conservation measures established by the 1994 Northwest Forest Plan to have helped the species.
“Murrelet populations were not expected to respond rapidly to protection of their nesting habitat on federal lands, nor to the Plan’s measures to increase the amount of old forests on its lands,” they write. “New murrelet nesting habitat — forest with large old trees — is expected to take a century or more to develop on cutover lands.” |