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Accurate estimates of vital rates like survival and reproduction are the foundation for endangered species management and recovery planning. Where new data are collected, analyses and conservation actions can be updated according to the best available knowledge. In this short communication, we update vital rate estimates for the Hawaiian Common Gallinule (Gallinula galeata sandvicensis), an endangered subspecies endemic to the Hawaiian Islands of Kaua'i and O'ahu, using newly available field data. These new data more than double the sample size used for initial vital rate estimates from a 2018 publication, and include the first ever published estimates of brood survival for this subspecies. The latter is considered a major knowledge gap for population modeling and conservation planning for this taxon. We estimated the mean probability of brood survival for the first month post-hatch at 0.90 for both islands combined, 0.82 on Kaua'i and 0.98 on O'ahu. For both populations combined, we observed a smaller mean clutch size (4.76 vs. 5.10), similar mean nest success (0.64 vs. 0.66), similar brood size (2.55 vs. 2.51), lower brood size per successful nest (3.77 vs. 3.86), and similar hatch rate (0.53 vs. 0.52) to the original study published in 2018. Received 13 May 2023. Accepted 28 December 2023. Key words: brood survival, chick survival, citizen science, nest success, Rallidae, wildlife management. Las estimaciones precisas de tasas vitales como supervivencia y reproducion son la base para la gestion de especies amenazadas y la planificacion de su recuperation. Cuando se recopilan nuevos datos, los analisis y acciones de conservation se deben actualizar de acuerdo con el mejor conocimiento disponible. En este articulo, actualizamos las estimaciones de las tasas vitales para Gallinula galeata sandvicensis, una subespecie en peligro y endemica de las islas hawaianas de Kaua'i y O'ahu, utilizando datos de campo recientemente disponi-bles. Estos nuevos datos aumentan la cantidad de datos de muestra utilizado para las estimaciones iniciales de las tasas vitales en el manuscrito original publicado en 2018. Ademas, describe las pri-meras estimaciones publicadas de la supervivencia de los polluelos durante el primer mes posterior a la eclosion para esta subespecie. El promedio de los datos de supervivencia fue 0.90 para ambas islas combinadas, 0.82 en Kaua'i y 0.98 en O'ahu. Para ambas poblaciones combinadas, se observe>> un promedio de nidada mas pequeno (4.76 contra 5.10), una tasa de exito de anidacion media similar (0.64 contra 0.66), tamano de cria similar (2.55 contra 2.51), menor tamano de cria por nido exitoso (3.77 contra 3.86), y una tasa de eclosion similar (0.53 contra 0.52) que el estudio original publicado en 2018, con un tamano de muestra 2 veces mayor del estudio original. Palabras clave: ciencia ciudadana. exito de anidacion, manejo de fauna silvestre. Rallidae, sobrevivencia de polluelos, sobrevivencia de puesta., Effective management planning for endangered species depends in part on accurate vital rate estimates (Beissinger and Westphal 1998, Reed et al. 2002). Vital rates include metrics of reproduction and survival [...]

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Summary: Knowledge of species-specific spatial ecology is critical for applying appropriate management strategies to maximise conservation outcomes. We used radio-telemetry to describe spatial behaviour of the critically endangered, island-endemic Mariana Crow Corvus kubaryi. To determine whether management strategies should reflect life stage, we measured the home ranges and daily movements of 22 Mariana Crows. Fledgling mobility was low during the first 31 days post-fledging and effects of age (fledgling or sub-adult) and time (months post-fledging or post-dispersal) were often driven entirely by this period. After controlling for reduced fledgling mobility, cumulative home range size increased over time for both age classes and was, on average, more than twice the area for sub-adults than fledglings. Sub-adults also tended to make longer daily movements than fledglings. Non-cumulative, monthly home range areas did not increase over time but the average overlap in home range area between consecutive months was only 63%, suggesting large shifts in space use each month. These results highlight the dynamic nature of Mariana Crow home ranges and suggest that large-scale management efforts are critical for protecting both breeding and non-breeding individuals. The application of the traditional home range concept to Mariana Crows and other wide-ranging passerine birds may result in sub-optimal management strategies. Instead, we recommend that the spatial and temporal scale of conservation efforts be informed by species-specific spatial behaviour across all relevant life stages. [ABSTRACT FROM AUTHOR]