Compensatory recruitment is a key demographic mechanism that has allowed the coexistence of populations of susceptible amphibians with Batrachochytrium dendrobatidis (Bd), a fungus causing one of the most devastating emerging infectious disease ever recorded among vertebrates. However, the underlying processes (e.g. density‐dependent increase in survival at early life stages, change in reproductive traits) as well as the level of interpopulation variation in this response are poorly known. We explore potential mechanisms of compensatory recruitment in response to Bd infection by taking advantage of an amphibian system where male reproductive traits are easy to quantify in free‐living populations. The Southern Darwin's frog Rhinoderma darwinii is a vocal sac‐brooding species that exhibits a high susceptibility to lethal Bd infection. Using a 7‐year capture–recapture study at four populations with contrasting Bd infection status (one high prevalence, one low prevalence and two Bd‐free populations), we evaluated whether Bd‐positive populations exhibited a higher adult recruitment and a higher male reproductive effort than Bd‐negative populations. We also estimated population growth rates to explore whether recruitment compensated for the negative impacts of Bd on the survival of adults. In addition, we evaluated a potential demographic signal of compensatory recruitment (i.e. positive relationship between the proportion of juveniles and Bd prevalence) in response to Bd infection using raw count data from 13 R. darwinii populations. The high Bd prevalence population exhibited the highest male reproductive effort and the highest recruitment among the four monitored populations. This led to a growing population during the study period despite high mortality of adult hosts. In contrast, males from the population with low Bd prevalence had a low reproductive effort and this population, which had the lowest adult recruitment, was declining during the study period despite adults having a higher survival in comparison to the high Bd prevalence population. We also found a demographic signal of compensatory recruitment in response to Bd infection in our broader analysis of 13 R. darwinii populations. Our study underlines the importance of interpopulation variation in life‐history strategies on the fate of host populations after infectious disease emergence. Our results also suggest that an increase in reproductive effort can be one of the processes underlying compensatory recruitment in populations of Bd‐susceptible amphibians.

Darwin's frogs Rhinoderma darwinii and Rhinoderma rufum are the only known species of amphibians in which males brood their offspring in their vocal sacs. We propose these frogs as flagship species for the conservation of the Austral temperate forests of Chile and Argentina. This recommendation forms part of the vision of the Binational Conservation Strategy for Darwin's Frogs, which was launched in 2018. The strategy is a conservation initiative led by the IUCN SSC Amphibian Specialist Group, which in 2017 convened 30 governmental, non-profit and private organizations from Chile, Argentina and elsewhere. Darwin's frogs are iconic examples of the global amphibian conservation crisis: R. rufum is categorized as Critically Endangered (Possibly Extinct) on the IUCN Red List, and R. darwinii as Endangered. Here we articulate the conservation planning process that led to the development of the conservation strategy for these species and present its main findings and recommendations. Using an evidence-based approach, the Binational Conservation Strategy for Darwin's Frogs contains a comprehensive status review of Rhinoderma spp., including critical threat analyses, and proposes 39 prioritized conservation actions. Its goal is that by 2028, key information gaps on Rhinoderma spp. will be filled, the main threats to these species will be reduced, and financial, legal and societal support will have been achieved. The strategy is a multi-disciplinary, transnational endeavour aimed at ensuring the long-term viability of these unique frogs and their particular habitat.

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Se sintetiza el conocimiento sobre el impacto de las plantaciones de Eucalyptus Sp. sobre algunos suelos de Uruguay (Acrisoles, Luvisoles, Argisoles, Inceptisoles), generados en trabajos del Dpto. de Suelos y Aguas de la FA-UDELAR. En 12 casos estudiados los suelos forestados presentaron menor pH, más aluminio intercambiable y menor saturación en bases que los que permanecen bajo las pasturas previas. En siete casos estudiados, el carbono orgánico mostró una tendencia a la disminución en la parte superior del horizonte A. En otros horizontes no surgen resultados claros, aunque en algunos sitios se observó una tendencia hacia el aumento de carbono orgánico en la base del A o inicio del B en los suelos forestados, comparados con los que permanecen bajo la pastura original. Si bien estos cambios de distribución vertical podrían no determinar cambios en el contenido de carbono del perfil, la presencia del mantillo (horizonte O) en los suelos forestados permitiría concluir que en las plantaciones forestales ocurre un aumento en la cantidad total de carbono orgánico del suelo. En un monitoreo de cinco años, el contenido de agua del suelo forestado fue siempre menor que bajo pastura: en verano, por la mayor evapotranspiración, y en invierno por la menor capacidad de retención de agua. Dos ensayos mostraron que el estado de degradación del suelo por su uso previo impactó significativamente en la productividad. Si se logra buen control químico de la vegetación preexistente y de las malezas, el laboreo de los suelos respecto al no-laboreo, no arroja diferencias para la plantación de eucaliptos, independientemente del uso previo.