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Recognizing the imperative to evaluate species recovery and conservation impact, in 2012 the International Union for Conservation of Nature (IUCN) called for development of a "Green List of Species" (now the IUCN Green Status of Species). A draft Green Status framework for assessing species' progress toward recovery, published in 2018, proposed 2 separate but interlinked components: a standardized method (i.e., measurement against benchmarks of species' viability, functionality, and preimpact distribution) to determine current species recovery status (herein species recovery score) and application of that method to estimate past and potential future impacts of conservation based on 4 metrics (conservation legacy, conservation dependence, conservation gain, and recovery potential). We tested the framework with 181 species representing diverse taxa, life histories, biomes, and IUCN Red List categories (extinction risk). Based on the observed distribution of species' recovery scores, we propose the following species recovery categories: fully recovered, slightly depleted, moderately depleted, largely depleted, critically depleted, extinct in the wild, and indeterminate. Fifty-nine percent of tested species were considered largely or critically depleted. Although there was a negative relationship between extinction risk and species recovery score, variation was considerable. Some species in lower risk categories were assessed as farther from recovery than those at higher risk. This emphasizes that species recovery is conceptually different from extinction risk and reinforces the utility of the IUCN Green Status of Species to more fully understand species conservation status. Although extinction risk did not predict conservation legacy, conservation dependence, or conservation gain, it was positively correlated with recovery potential. Only 1.7% of tested species were categorized as zero across all 4 of these conservation impact metrics, indicating that conservation has, or will, play a role in improving or maintaining species status for the vast majority of these species. Based on our results, we devised an updated assessment framework that introduces the option of using a dynamic baseline to assess future impacts of conservation over the short term to avoid misleading results which were generated in a small number of cases, and redefines short term as 10 years to better align with conservation planning. These changes are reflected in the IUCN Green Status of Species Standard.Reconociendo que era imperativo evaluar la recuperación de especies y el impacto de la conservación, la Unión Internacional para la Conservación de la Naturaleza (UICN) convocó en 2012 al desarrollo de una “Lista Verde de Especies” (ahora el Estatus Verde de las Especies de la UICN). Un marco de referencia preliminar de una Lista Verde de Especies para evaluar el progreso de las especies hacia la recuperación, publicado en 2018, proponía 2 componentes separados pero interconectados: un método estandarizado (i.e., medición en relación con puntos de referencia de la viabilidad de especies, funcionalidad y distribución antes del impacto) para determinar el estatus de recuperación actual (puntuación de recuperación de la especie) y la aplicación de ese método para estimar impactos en el pasado y potenciales de conservación basados en 4 medidas (legado de conservación, dependencia de conservación, ganancia de conservación y potencial de recuperación). Probamos el marco de referencia con 181 especies representantes de diversos taxa, historias de vida, biomas, y categorías (riesgo de extinción) en la Lista Roja de la IUCN. Con base en la distribución observada de la puntuación de recuperación de las especies, proponemos las siguientes categorías de recuperación de la especie: totalmente recuperada, ligeramente mermada, moderadamente mermada, mayormente mermada, gravemente mermada, extinta en estado silvestre, e inderterminada. Cincuenta y nueve por ciento de las especies se consideraron mayormente o gravemente mermada. Aunque hubo una relación negativa entre el riesgo de extinción y la puntuación de recuperación de la especie, la variación fue considerable. Algunas especies en las categorías de riesgo bajas fueron evaluadas como más lejos de recuperarse que aquellas con alto riesgo. Esto enfatiza que la recuperación de especies es diferente conceptualmente al riesgo de extinción y refuerza la utilidad del Estado Verde de las Especies de la UICN para comprender integralmente el estatus de conservación de especies. Aunque el riesgo de extinción no predijo el legado de conservación, la dependencia de conservación o la ganancia de conservación, se correlacionó positivamente con la potencial de recuperación. Solo 1.7% de las especies probadas fue categorizado como cero en los 4 indicadores de impacto de la conservación, lo que indica que la conservación ha jugado, o jugará, un papel en la mejoría o mantenimiento del estatus de la especie la gran mayoría de ellas. Con base en nuestros resultados, diseñamos una versión actualizada del marco de referencia para la evaluación que introduce la opción de utilizar una línea de base dinámica para evaluar los impactos futuros de la conservación en el corto plazo y redefine corto plazo como 10 años.

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.