ROCKPORT, Texas (March 23, 2009)--Wildlife managers are worried that some of the whooping cranes wintering at Aransas National Wildlife Refuge may be too weak and malnourished to successfully make their return to Canada this season.

The drought has had an effect on the flock of whooping cranes that spends each winter on the Texas Gulf Coast.

The birds have had trouble finding food because low water levels have decreased the number of blue crabs.

U.S. Fish and Wildlife Service whooping crane coordinator Tom Stehn says these are the worst conditions he's seen and describes thin birds with disheveled plumage.

Wildlife manager Dan Alonso says they've tried to help supplement the cranes' diet by setting up 13 deer feeders with corn at the refuge.