Chapter 13 - Winter Habitat Ecology, Use, and Availability for the Aransas-Wood Buffalo Population of Whooping Cranes

Abstract

Whooping Cranes in the Aransas-Wood Buffalo Population (AWBP) depend upon healthy coastal ecosystems along the central Texas Coast throughout their wintering period. They use large, continuous expanses of undeveloped coastal marshes, unvegetated flats, and coastal ponds within their defended territories, as well as adjacent seagrass beds, coastal prairies, and freshwater marshes for essential alternate food and freshwater needs. Historically, Whooping Cranes encompassed a broader extent of wintering areas along the northwestern Gulf of Mexico; however, the last remaining 15 wild cranes were only located along a single peninsula within the Aransas National Wildlife Refuge in 1941. As this remnant population has increased to >330 individuals, their wintering range has expanded beyond protected refuge boundaries into two adjacent coastal bay systems. We use published, long-term spatial data sets to quantify the amount of various habitats that used by AWBP Whooping Cranes in the winter, and to identify potential areas Whooping Cranes may use as they continue their range expansion. The results are further used to determine if sufficient habitats are currently, and will be, available to support various population targets identified in the current recovery plan. Finally, we explore the cumulative impacts of anthropogenic stressors on habitat quality potentially affecting habitat availability and extent needed in the AWBP Whooping Crane’s wintering range.