Comparative Conservation Strategy Efficacy for Grus japonensis and Grus americana: A Post-Policy Implementation Assessment

Abstract

Abstract Southeastern Texas/northern Alberta and northeastern Japan are homes to populations of two extremely similar species of cranes with similar conservation histories. The whooping crane of North America, specifically the Aransas–Wood Buffalo (AWB) migratory flock, and the red-crowned crane of Hokkaido were both pushed to the brink of extinction with surviving populations numbering 21 and 33 individuals, respectively, in 1952. Both species have been subjects of focused rehabilitation efforts led by national governments. While both governments relied on a variety of conservation methods throughout their programs’ histories, the U.S. Fish & Wildlife Service (FWS) focuses mainly on habitat management, while in Japan the Ministry of the Environment (MoE) and its predecessors lean most heavily on a direct population management strategy via a long-standing winter artificial feeding program. The recovery histories of these two similar species provide a unique opportunity for comparing and contrasting the relative efficacy of two primary endangered species management approaches: habitat management versus direct population management through artificial feeding. An initial review of these two case studies reveals indications that artificial feeding in periods of lean food availability resulted in much faster overall population recovery in Japan, with the red-crowned crane population expanding at a rate approximately 11% to 26% faster than the AWB whooping crane population over a 68-year period reviewed in this study. Today Japan’s red-crowned crane population is more than triple the size of North America’s AWB whooping crane population: 1,900 red-crowned cranes by 2020 according to the Red-Crowned Crane Conservancy (RCCC), versus 506 AWB whooping cranes as of 2019 per FWS. These results suggest Japanese conservationists may have uncovered a method for ensuring faster population recovery in an endangered species: sustained long-term artificial feeding during times of least forage availability. Further lessons can be drawn from how these two species respond to changes currently underway in both programs. Much remains unknown. Additional research is necessary to eliminate other variables that could explain these population growth outcomes. But an early post-policy implementation assessment points to the artificial feeding campaign in Japan as the reason for the differences in historical population recovery.