Pelicans return to N.D.'s Chase Lake

updated 8:28 a.m. ET June 20, 2005

CHASE LAKE NATIONAL WILDLIFE REFUGE, N.D. - From an airplane a half-mile above white pelican nesting grounds here, the giant birds are hard to miss.  Measuring 6 feet from bill to tail and weighing up to 20 pounds each, the birds look like moving patches of snow on the islands of Chase Lake. 

Wildlife officials estimate 18,850 breeding adults have returned to this 4,385-acre refuge in central North Dakota, which had been known for a century as the home of the largest nesting colony of white pelicans in North America. But this time last year, the nesting grounds were empty, leaving an ornithological mystery that biologists say may never be solved.

Nearly 28,000 birds took off last summer.  The rookery was littered with eggs and chicks that did not survive.

Pelicans began returning in early April, and biologists hope they will stay put through September, caring for their hatchlings and feasting on small fish and foot-long salamanders from nearby prairie potholes.

"The good news is the pelicans have returned and no birds have left that we're aware of," said Ken Torkelson, a spokesman for the U.S. Fish and Wildlife Service in Bismarck.  "We'd happier if 30,000 birds returned, but on a disappointment scale, this ranks very low."

The white pelican is one of the largest birds in North America, with a wingspan of nearly 10 feet.  It lives about 25 years.

Biologists have been doing aerial surveys of the nesting grounds since 1972, using photographs scanned into a computer program to count the exact number of breeding birds.  This year's breeding population is the lowest since 1997, when 18,364 birds were counted.

The birds abandoned the nesting ground before a survey could be taken last year.  In 2000, biologists recorded 35,466 pelicans, a record.

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