The only known breeding population of whooping cranes nests in and around Wood Buffalo National Park in the southern Northwest Territories and northern Alberta. This population winters along the coast of Texas near Corpus Christi on the Aransas National Wildlife Refuge, Matagorda Island, Isla San Jose, and portions of the Lamar Peninsula and Welder Point, which is on the east side of San Antonio Bay known as Welder Point. Many of the ponds have border growths of bulrushes and cattails, which occasionally cover entire bays and arms of the larger lakes.
Whooping cranes are omnivorous feeders.
In December and January the tidal flats and sloughs drain and the birds move into shallow bays and channels to forage. In these areas whooping cranes feed primarily on clams of at least six species. Potential hazards to whooping cranes increase as human use of crane habitat increases. Barges carrying chemicals occupy the Gulf Intracoastal Waterway through the whooping cranes' wintering habitat every day. A spill or leak of these chemicals could contaminate the cranes' food supply, or poison or injure the cranes directly.