Natural History of the Marbled Murrelet


The marbled murrelet is listed as threatened under the Endangered Species Act in California, Oregon, and Washington; British Columbia is also protecting it, and it seems to be abundant but possibly declining in Alaska. The marbled murrelet is threatened by the loss and modification of nesting habitat primarily due to commercial timber harvesting. It is also threatened from mortality associated with gill net fishing off the Washington coast and the effects of oil spills. It is unusual in that it is a sea bird that nests in trees, and those nests need to be near the coast. The marbled murrelet has webbed feet so it needs trees with big branches for nesting sites. For the most part the marbled murrelet needs old growth to nest, and there isn’t much old growth left close to the coast in the lower forty-eight.

The marbled murrelet is pretty easy to see out on the water, although they are shy of people, but they are difficult to observe inland. They are about the size of a robin, they nest high up in old growth stands, they are well camouflaged, especially in the breeding season, and they fly through the woods at about sixty miles per hour. In fact where and how they nested were mysteries for many years; no one seemed to know that these seabirds nested in trees.

The marbled murrelet and the spotted owl, became a flagship species and a political football during the Northwest timber wars of the early 1990’s. In unusually blunt language a federal judge (William Dwyer) told federal agencies that they had to do a much better job enforcing the Endangered Species Act. The Forest Service manages most of the federally owned timberland in the Northwest, and by the early 1990s 80 to 90 percent of the old growth had been cut over and the timber industry had its eyes on the rest of it. Suddenly there was a lot of interest in this small seabird that hardly anyone had ever recognized as using inland, old growth habitat.

In fact the marbled murrelet is more dependent on old growth than the spotted owl. Spotted owls need old growth for nesting but they can use younger woods for foraging. Murrelets need both marine habitat with lots of small fish, and good nesting habitat; that is, dense stands of big, old trees within commuting distance of the ocean.

We spoke with Carolyn Meyer about marbled murrelets and her research on their habitat requirements.

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