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This paper reviews the population trends and threats for the 15 species of cranes, and comments on conservation priorities for the family as a whole. Cranes occur on five continents, with greatest diversity in East Asia (nine species) and Sub-Saharan Africa (six species). Eleven crane species are threatened with extinction according to the IUCN Red List, including one species Critically En- dangered, three species Endangered, and seven species Vulnerable. Of the four species of Least Con- cern, population sizes for the Demoiselle (Anthropoides virgo) and Brolga (Grus rubicunda) are not well known but these species are declining in some areas. The Sandhill (G. canadensis) and Eurasian Cranes (G. grus) are the most abundant cranes and have rapidly increased in part due to their flexible selection of foraging habitats and use of agriculture lands and waste grain as a food source. Status for six species — Grey Crowned (Balearica regulorum), Blue (Anthropoides paradise), Black-necked (G. nigricollis), Red-crowned (G. japonensis), Sandhill, and Siberian (G. leucogeranus) — are summarized in more detail to illustrate the diversity of population shifts and threats within the crane family. A crane threat matrix lists the major threats, rates each threat for each species, and scores each threat for the crane family as a whole. Four of the five greatest threats are to the ecosystems that cranes depend upon, while only one of the top threats (human disturbance) relates to human action directly impact- ing on cranes. Four major threats are discussed: dams and water diversions, agriculture development, crane trade, and climate change. Conservation efforts should be strongly science-based, reduce direct threats to the birds, safeguard or restore habitat, and strengthen awareness among decision makers and local communities for how to safeguard cranes and wetlands. Especially for the most severely threatened species, significantly stronger efforts will be needed to incorporate our understanding of the needs of cranes and the ecosystems they inhabit into decisions about agriculture, water manage- ment, energy development and other human activities.

We sought to refine genetic management of the endangered Whooping Crane (Grus americana) population by developing comprehensive genetic pedigrees for the captive population. Improvements to the studbook were accomplished by addition of pedigree information derived from leg-banding data on wild ju- venile andfounder similarity coefficients calculatedfrom microsatellite DNA profiles to the original studbook pedigree. Incorporation of pedigrees derived from data on leg-banding of wild juveniles did not greatly alter the previous relatedness structure of the captive population, but incorporation of microsatellite similarity co- efficients produced a substantially different view of the population structure. Microsatellite data provided new information on shared founder genotypes and provided a new DNA-based studbook pedigree that will assist in genetic management of the Whooping Crane population.

Population viability analysis (PVA) is widely used in conservation biology to compare management strategies and predict probabilities of extinction for endangered species. However, it remains unclear whether the available range of generic PVA programs produce similar predictions when applied to common data sets. A comparative analysis was carried out using six commonly applied PVA packages (GAPPS, INMAT, RAMAS Age, RAMAS Metapop, RAMAS Stage and VORTEX), based on the extensive population data available for the endangered whooping crane, Grus americana. Significant differences were found between the projections of the PVA packages. In particular, the introduction of stochastic variation in breeding structure led to large differences between some packages. Surprisingly, two versions of VORTEX produced very different predictions due to a subtle difference in the way monogamous breeding was modelled. The pattern of similarities and differences among the projections of the packages differ depending on the species examined. In contrast to the predictions of comprehensive (realistic) models, simplified (standardized) models were found to be relatively congruent, which probably reflects similarities in the fundamental biological processes being modelled by the PVA packages. The implications for conservation are clear; caution must be exercised when interpreting the projections of a model built using any one PVA package since, due to seemingly subtle differences in what biological assumptions and threatening processes are included in the models, the predictions among PVA packages (or versions of the same program) are not necessarily concordant.