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A decline in the numbers of threatened species is often reversed by reintroduction with the aim of repopulating or strengthening the population to reduce the risk of extinction. The success of reintroduction programs is associated with demographic and genetic monitoring of the reintroduced populations. We undertook a genetic assessment of the Critically Endangered gharial (Gavialis gangeticus) to assess the current level of genetic variation using three partial mitochondrial (mt) DNA regions: cytochrome b, cytochrome c oxidase subunit-I and the control region. We sequenced 103 samples collected across 14 nesting sites. A low level of mtDNA variation was observed in the sampled population (hd = 0.462 ± 0.048; Pi = 0.00029 ± 0.00004). Only five distinct haplotypes were observed in three segregating sites. This is the first assessment of the genetic variation in the wild gharial population to be made using mtDNA. Homogeneity in the 520 bp hypervariable control region of the crocodilian mtDNA is reported here for the first time. The low mitochondrial diversity and no genetic structure in the sampled population is indicative of a genetic bottleneck, the founder effect and probably associated with humanassisted augmentation of the population of the gharial. An extremely low level of genetic variation in the largest gharial population highlights the vulnerability of the gharial population in the wild and calls for immediate genetic assessment of other gharial populations so that a robust conservation plan focusing on connectivity and enhanced protection can be developed for the long-term persistence of the gharial in the wild.

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.

The gharial, Gavialis gangeticus (Gmelin 1789), a piscivorous reptile of Asian river systems, is increasingly threatened by diverse human pressures. Three survey expeditions were launched to monitor gharial populations, notable wildlife, and the activities and attitudes of local people in a 110km stretch of the Chambal River in the National Chambal Reserve (NCS), India. Only 15% of gharial observed in December 2009 were in the upstream 54% of the surveyed river length. This coincides with the highest density of disturbance including water pumps, fishermen, and the highest growth in fishing activity since December 2008. Although fishing is recognized as a significant threat to gharial, no strong relationship was found between numbers of gharial and fishermen. However, numbers of water pumps, indicative of the intensity of agricultural activity, had a negative relationship with gharial numbers. This relationship was strengthened by omitting the upstream (Pali to Rameshwaram) survey reach, the tourist area of the NCS, which is also potentially affected by upstream reaches. The downstream 46% of surveyed river length in December 2009 supported 85% of gharial (consistent with trends in other surveys), including 91.6% of males and 81.8% of juveniles. This reach is classified as a High Population Recorded Area of high potential conservation importance, also containing better habitat quality and lower human disturbance. A positive relationship was found between gharial numbers and sand habitat features. However, the Davar to Ghoonsai survey reach had low gharial numbers despite abundant sand features, perhaps due to a substantial length of the Ghoonsai sand bank having been converted or agriculture. This may have significant implications for gharial conservation. Copyright © 2011 John Wiley & Sons, Ltd. Copyright © 2011 John Wiley & Sons, Ltd. 21 4 June 2011 10.1002/aqc.1195 Research Article Research Articles Copyright © 2011 John Wiley & Sons, Ltd..