Whooping crane population declines for first time in almost a decade
A flock of endangered whooping cranes has begun its spring migration to breeding grounds in Canada, but it has experienced a population decline for the first time in almost a decade.
This past winter was the worst on record in terms of bird deaths, according to Tom Stehn, whooping crane coordinator with the U.S. Fish and Wildlife Service.
"Total winter mortality is estimated at six adults and 15 chicks, a loss of 7.8% of the flock," Stehn stated. "When added to the 34 birds that left Texas in spring 2008 and failed to return in 2009, 20% of the flock was lost during the last 12 months."
Stehn attributes the winter losses to poor habitat conditions at the Aransas National Wildlife Refuge in Texas, which the birds migrate to each fall. Low rainfall totals resulted in saltier bays and also fewer blue crabs, the primary food source for the cranes.
This marks the first year that bird numbers have fallen since 2001 for one of the last remaining wild populations of whooping cranes.
However, population decreases are not unheard of for these birds and have been documented in the past.
"Although whooping crane numbers have experienced an amazing upward climb since conservation efforts began in the 1930s, over the course of their recovery we have occasionally seen short-term dips in the population," said Lee Ann Linam, biologist in the Wildlife Diversity Program at the Texas Parks and Wildlife Department.
Whooping cranes are one of the rarest bird species in North America, with only three populations known to exist.
Hopefully this flock will rebound with the help of new births after their migration.
-- Kelly Burgess
Photos: Whooping cranes at the Aransas National Wildlife Refuge. Credit: Texas Parks and Wildlife Department