Identifying, Protecting and Managing Stopover Habitats for Wild Whooping Cranes on U.S. Army Corps of Engineers Lakes

The Whooping Crane (Grus americana) is one of North America’s most endangered species. There is only one wild, self-sustaining migratory population of Whooping Cranes, the Aransas–Wood Buffalo population (AWBP). The birds of the AWBP migrate 4,000 km twice each year between their nesting grounds in northern Canada and their wintering grounds on the Texas Gulf Coast. During migration, AWBP Whooping Cranes must land at suitable ponds or wetlands to forage, rest or roost. The Whooping Crane Recovery Plan, developed by federal wildlife agencies in Canada and the USA, calls for the protection and management of Whooping Crane stopover locations within the migration corridor. Although major stopover areas have been protected, many other smaller sites remain to be identified. However, the Recovery Plan offers no specific entity to identify, protect and manage the latter. To address these deficiencies in information and activity, Friends of the Wild Whoopers partnered with the United States Army Corps of Engineers (USACE) within the AWBP migration corridor to share information about Whooping Cranes and their habitat needs and identify potential stopover locations on USACE properties that could be protected and managed for cranes. This partnership identified 624 potential stopover sites on 34 USACE lakes, principally in North and South Dakota, Nebraska, Kansas, Oklahoma and Texas, with commitments to manage the habitats as resources allow.

William Rowan and Canada’s 5¢ Whooping Crane stamp: the proposal and a Saskatchewan photograph

This article focused on the photograph of two Whooping Cranes in Saskatchewan that William Rowan used as a basis of a stamp issued by Canada Post in 1955. Details of the proposal submitted in support of this issue are outlined.

Heterogeneity in migration strategies of Whooping Cranes

Migratory birds use numerous strategies to successfully complete twice-annual movements between breeding and wintering sites. Context for conservation and management can be provided by characterizing these strategies. Variations in strategy among and within individuals support population persistence in response to changes in land use and climate. We used location data from 58 marked Whooping Cranes (Grus americana) from 2010 to 2016 to characterize migration strategies in the U.S. Great Plains and Canadian Prairies and southern boreal region, and to explore sources of heterogeneity in their migration strategy, including space use, timing, and performance. Whooping Cranes completed ~3,900-km migrations that averaged 29 days during spring and 45 days during autumn, while making 11–12 nighttime stops. At the scale of our analysis, individual Whooping Cranes showed little consistency in stopover sites used among migration seasons (i.e. low site fidelity). In contrast, individuals expressed a measure of consistency in timing, especially migration initiation dates. Whooping Cranes migrated at different times based on age and reproductive status, where adults with young initiated autumn migration after other birds, and adults with and without young initiated spring migration before subadult birds. Time spent at stopover sites was positively associated with migration bout length and negatively associated with time spent at previous stopover sites, indicating Whooping Cranes acquired energy resources at some stopover sites that they used to fuel migration. Whooping Cranes were faithful to a defined migration corridor but showed less fidelity in their selection of nighttime stopover sites; hence, spatial targeting of conservation actions may be better informed by associations with landscape and habitat features rather than documented past use at specific locations. The preservation of variation in migration strategies existing within this species that experienced a severe population bottleneck suggests that Whooping Cranes have maintained a capacity to adjust strategies when confronted with future changes in land use and climate.