Pelican Deaths

Fish and Wildlife Service is investigating the deaths of thousands of young white pelicans at a wildlife refuge in central North Dakota, a year after thousands of adult birds abruptly left the same location.

The white pelican, one of the largest birds in North America, breeds only once a year, and males and females take turns caring for their young. The birds have a wingspan of nearly 10 feet and live about 25 years.

The pelicans normally stay at the Chase Lake refuge through September, raising their young and feasting on crawfish, small fish and foot-long salamanders from small ponds known as prairie potholes.

At least 8,000 chicks may have died over the past two months, said Ken Torkelson, a spokesman for the Chase Lake National Wildlife Refuge.

"The difference is, last year the adults left first," he said. "This year, the young have died and the adults have no reason to stick around."

Officials had hoped the refuge would return to normal after nearly 30,000 adult pelicans took off last year, leaving their young behind. Officials still can't determine what caused last year's exodus.

Severe storms or a disease outbreak may have caused the mass die-off, said Marsha Sovada, a biologist at the U.S. Geological Survey's Northern Prairie Wildlife Research Center in Jamestown.

Excerpts taken from MSNBC.