Periodic Status Review for the Brown Pelican (2016)

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Published: October 2015

Pages: 41

Author(s): Derek W. Stinson

Executive Summary

The Brown Pelican (Pelecanus occidentalis) is currently listed as endangered by the state of Washington. The Pacific coast and Gulf of Mexico populations were delisted by the U. S. Fish and Wildlife Service under the Endangered Species Act in 2009. These populations were listed as federally endangered in 1970 in response to widespread pollutant-related reproductive failures and the population declines that directly resulted.

The Brown Pelicans present seasonally in Washington belong to the California subspecies (P. o. californicus). They nest on islands in the Gulf of California and along the coast of Baja California in Mexico north to Channel Islands National Park in southern California. California Brown Pelicans disperse north seasonally along the Pacific coast from nesting areas in search of food, with small numbers dispersing as far as southern British Columbia. Birds occur in Washington’s coastal waters, mainly from April through November with a peak in late July to early September; their numbers decline in October and November with the onset of stormy weather. The total metapopulation of California Brown Pelicans has been estimated at 70,000 breeding pairs.

Roosting and loafing sites are important for Brown Pelicans. They seek secure night roosting sites, and after feeding, they roost out of the water while they dry and preen their plumage because their feathers become water-logged. In Washington, Brown Pelicans gather in roosts on sandy islands, exposed shoals, and a few artificial structures in the Columbia River, Grays Harbor, and Willapa Bay estuaries, and rocky islands off the coast of the Olympic Peninsula. East Sand Island, Oregon, in the Columbia River estuary is currently the largest night roost for Brown Pelicans in the region, where their annual peak numbers have increased markedly from <100 during 1979-1986 to a high of >16,000 in 2009. Since that time, numbers have declined somewhat during surveys, but may reflect more dispersed roosting and a more variable peak.

California Brown Pelicans feed primarily on small schooling fishes, including Pacific Sardines, Northern Anchovies, and Pacific Mackerel. The steady increase in Brown Pelican numbers in Washington from 1987-2011, was likely due to cyclic changes in ocean conditions that affect forage fish abundance, and also, perhaps the recovery of nesting colonies in the Southern California Bight. Natural fluctuations in ocean conditions and forage fish abundance have caused dramatic changes in pelican abundance in Washington in the past, and a crash in sardine populations has led to ~4 consecutive years of extremely poor reproductive success at their southern colonies.

Although the recent breeding failures, unprecedented ocean warming, toxic algae blooms, and climate change present uncertainty about the future trend in Brown Pelican populations, robust numbers (>10,000) still occur seasonally in Washington, and they are not immediately threatened. We recommend that the Brown Pelican be removed from Washington’s list of endangered species. Because Brown Pelicans concentrate at roosts, particularly at night, they should remain as a Priority Species due to these vulnerable aggregations. Brown Pelicans are protected from ‘take’ by federal law under the Migratory Bird Treaty Act, and would remain a ‘protected wildlife’ species by state law if they are delisted. As required in WAC 232-12-297, the status of Brown Pelicans in Washington will be reviewed again in five years.

Suggested citation

Stinson, D. W. 2014. Periodic status review for the Brown Pelican. Washington Department of Fish and Wildlife, Olympia, Washington. 32 + iv pp.

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Draft documents are provided for informational purposes only. Drafts may contain factual inaccuracies and may not reflect current WDFW policy.