 A Pelican's Progress
The brown pelican, notable for its spectacular dives, has been removed from the endangered species list in all but four states.
By Elizabeth Daerr
The National Wildlife Refuge System, which includes nearly 93 million acres, owes its establishment to a single species-the brown pelican. Alarmed by the birds' slaughter for both their feathers and their appetite for fish, birding organizations urged President Theodore Roosevelt in 1903 to set aside Pelican Island, a three-acre parcel off central Florida, to provide nesting habitat.
Habitat protection combined with the passage of the Migratory Bird Treaty and public education helped the birds' populations increase. But by the 1960s, pelicans faced another challenge: environmental contaminants. Pelicans feed primarily on fish, and many adults died as a result of the buildup of toxins ingested along with the fish. In addition, the pesticide DDT, ingested with their food, caused birds to lay thin-shelled eggs that were broken or crushed during incubation.
By 1970, the brown pelican was added to the endangered species list from the coasts of the Chesapeake Bay south to Florida and west to Texas and California. That decade, the use of DDT was banned, and the discharge of the pesticide's effluent into ocean waters was curtailed. As a result, brown pelican breeding began to improve. Today, the birds have been removed from endangered status in all states but Mississippi, Louisiana, Texas, and California.
The birds have a remarkable wingspan, reaching six and a half feet across and are known for their spectacular dives—from as high as 60 feet—to scoop fish into their expandable pouch.
Various plumage characteristics distinguish a bird's stage of development. The head and neck of immature birds are mostly brown. The young birds fledge in 12 to 14 weeks, and by the time they leave the nest, they are heavier than their parents. The extra fat reserves allow them to survive while they learn to find food on their own. Adult birds have a white neck and head with a yellow crown in the winter and a dark brown hind neck and white head with a russet crest in the summer.
Although the brown pelican has made a remarkable comeback over the last 30 years, human interaction still kills many birds, according to Riley Hoggard, a natural resource specialist at Gulf Islands National Seashore in Florida and Mississippi. They can get tangled in disgarded monofilament fishing line or choke on a cleaned fish carcass that goes down tailfirst, he said, and occasionally the birds are hooked by an angler's cast. Although Hoggard helps injured birds, he said the problem will be hard to resolve on a long-term basis because the birds are attracted to the fishing piers and the possibility of an easy meal. Unfortunately, the more the birds are around fishermen, the greater the chance of injury, Hoggard said.
Frank Gress, a research ecologist with the University of California at Davis, has studied brown pelicans for nearly three decades at Channel Islands National Park and said that the breeding grounds in southern California are doing well.
In 1971, West Anacapa Island was set aside as a research natural area, and waters surrounding the colony were closed to boat traffic during the breeding season. The island supports the largest rookery on the West Coast, with an average of 4,000 to 5,000 breeding pairs each year. Gress said that the productivity of the colonies varies with food availability. The birds feed primarily on anchovies and sardines. Monofilament and fishing tackle entanglements are also a major problem with brown pelicans on the West Coast.
The Channel Island population is stable, and Gress suggests that the birds' endangered status be reviewed, but the U.S. Fish and Wildlife Service has been unable to pursue the project because of backlogs with other species. | |
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