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When facing an emerging infectious disease of conservation concern, we often have little information on the nature of the host-parasite interaction to inform management decisions. However, it is becoming increasingly clear that the life-history strategies of host species can be predictive of individual- and population-level responses to infectious disease, even without detailed knowledge on the specifics of the host-parasite interaction. Here, we argue that a deeper integration of life-history theory into disease ecology is timely and necessary to improve our capacity to understand, predict and mitigate the impact of endemic and emerging infectious diseases in wild populations. Using wild vertebrates as an example, we show that host life-history characteristics influence host responses to parasitism at different levels of organisation, from individuals to communities. We also highlight knowledge gaps and future directions for the study of life-history and host responses to parasitism. We conclude by illustrating how this theoretical insight can inform the monitoring and control of infectious diseases in wildlife.

Sexual signals in different animals are expected to be dimorphic when both sexes signal, but cases of monomorphism are known to occur, and we lack a clear understanding about the factors that modulate the level of sexual dimorphism in signals. In this study, we evaluated the hypothesis that the lack of dimorphism in sexual signals might evolve in systems experiencing temporal changing conditions of intra-sexual competition. We used the Darwin’s frog (Rhinoderma darwinii), a species with paternal care, as a model. We compared advertisement calls and examined call distinctiveness among females, pregnant and non-pregnant males in a wild population from Chiloe island, Chile. We also recorded the vocal activity of both sexes along the reproductive season. Additionally, we compared the acoustic properties of their advertisement calls in terms of sexual distinctiveness and individual repeatability. We found that the proportion of females and pregnant males vocalizing changed over time following distinct patterns. Females produced calls with lower dominant frequency and longer note and call durations than males, and these acoustic differences were related to body size differences between sexes, but only dominant frequency contributed significantly to the distinctiveness of calls between sexes. Also, individual repeatability was high, indicating that calling can be relevant for social recognition. Overall, our results suggest that mutual selective pressures could be involved in the limited dimorphism of the advertisement calls in Darwin’s frogs, as the sex ratio of individuals vocalizing (i.e. females vs. reproductive males) is reversed along the breeding period. Whether sexually monomorphic signals are evidence of adaptive mutual choice or a by-product of genetic constraints on females remains as an open question. In species with exclusive parental care of males, it would be expected that males and females alternate their reproductive availability while performing slightly differentiated sexual signals. Using acoustic recordings and capture-recapture data of the Darwin’s frog, we found that advertisement calls of this frog tend to be monomorphic. Interestingly, the males performing parental care were calling actively and the population had a clear bias in the number of males. Males and females of this endangered frog called actively, but the vocalization rate of each sex peaked at different times along the breeding season. These findings open new questions about the mechanisms of sexual recognition under restricted signal dimorphism.

Globalized infectious diseases are causing species declines worldwide, but their source often remains elusive. We used whole-genome sequencing to solve the spatiotemporal origins of the most devastating panzootic to date, caused by the fungus Batrachochytrium dendrobatidis, a proximate driver of global amphibian declines. We traced the source of B. dendrobatidis to the Korean peninsula, where one lineage, BdASIA-1, exhibits the genetic hallmarks of an ancestral population that seeded the panzootic. We date the emergence of this pathogen to the early 20th century, coinciding with the global expansion of commercial trade in amphibians, and we show that intercontinental transmission is ongoing. Our findings point to East Asia as a geographic hotspot for B. dendrobatidis biodiversity and the original source of these lineages that now parasitize amphibians worldwide., S.J.O., T.W.J.G., L.Br., A.Lo., A.A.C., D.S.S., E.A.C., C.M., J.B., D.M.A., F.C., and M.C.F. were supported through NERC (standard grant NE/K014455/1). S.J.O. acknowledges a Microsoft Azure for Research Sponsorship (subscription ID: ab7cd695-49cf-4a83-910a-ef71603e708b). T.W.J.G., A.Lo., A.A.C., D.S.S., E.A.C., C.M., J.B., D.M.A., F.C., and M.C.F. were also supported by the EU BiodivERsA scheme (RACE, funded through NERC directed grant NE/G002193/1 and ANR08-Biodiversa-002-03) and NERC (standard grant NE/K012509/1). M.C.F., E.A.C., and C.M. acknowledge the Nouragues Travel Grant Program 2014. R.A.F. was supported by an MIT/Wellcome Trust Fellowship. T.W.J.G. was supported by the People’s Trust for Endangered Species and the Morris Animal Foundation (D12ZO002). J.M.G.S. and M.C.F. were supported by the Leverhulme Trust (RPG-2014-273) and the Morris Animal Foundation (D16ZO-022). F.B. was supported by the ERC (grant ERC 260801–Big_Idea). D.M.A. was funded by Wellcome Trust grant 099202. J.V. was supported by the Hungarian Scientific Research Fund (OTKA K77841) and Bolyai János Research Scholarship, Hungarian Academy of Sciences (BO/00579/14/8). D.J.G. was supported by the Conservation Leadership Programme (grant 0134010) with additional assistance from F. Gebresenbet, R. Kassahun, and S. P. Loader. C.S.-A. was supported by Fondecyt Nº11140902 and 1181758. T.M.D.-B. was supported by the Royal Geographical Society and the Royal Zoological Society of Scotland with assistance from M. Hirschfeld and the Budongo Conservation Field Station. B.W. was supported by the National Research Foundation of Korea (2015R1D1A1A01057282). L.F.T. was supported by FAPESP (#2016/25358-3) and CNPq (#300896/2016-6). L.Be., L.F.S., and R.J.W. were supported by the Australian Research Council (FT100100375, DP120100811). A.A.C. was supported by a Royal Society Wolfson Research Merit award. J.H., A.La., and S.M. were funded by the Swedish Research Council Formas (grant no. 2013- 1389-26445-20). C.W. was funded by the National Research Foundation, South Africa. T.Y.J. and T.S.J. acknowledge NSF grant DEB-1601259. W.E.H. was funded by the NSERC Strategic and Discovery grant programs

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. Fil: Azat, Claudio. Universidad Andrés Bello; Chile Fil: Valenzuela Sánchez, Andrés. Universidad Austral de Chile; Chile Fil: Delgado, Soledad. Organización No Gubernamental (ong) Ranita de Darwin; Chile Fil: Cunningham, Andrew A.. The Zoological Society of London; Reino Unido Fil: Alvarado-Rybak, Mario. Universidad Andrés Bello; Chile Fil: Bourke, Johara. Tierärztliche Hochschule Hannover; Alemania Fil: Briones, Raúl. Arauco; Chile Fil: Cabeza, Osvaldo. Zoológico Nacional de Chile; Chile Fil: Castro-Carrasco, Camila. Universidad de Concepción; Chile Fil: Charrier, Andres. Centro Capesuc; Chile Fil: Correa, Claudio. Universidad de Concepción; Chile Fil: Crump, Martha L.. State University of Utah; Estados Unidos Fil: Cuevas, César C.. Universidad Católica de Temuco; Chile Fil: De La Maza, Mariano. Corporación Nacional Forestal Ministerio de Agricultura; Chile Fil: Díaz Vidal, Sandra. División de Recursos Naturales y Biodiversidad; Chile Fil: Flores, Edgardo. Fundación Nahuelbuta Natural; Chile Fil: Harding, Gemma. University Of Kent; Reino Unido Fil: Lavilla, Esteban Orlando. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - Tucumán. Unidad Ejecutora Lillo; Argentina Fil: Mendez, Marco A.. Universidad de Chile; Chile Fil: Oberwemmer, Frank. Zoo Leipzig; Alemania Fil: Carlos Ortiz, Juan. Universidad de Concepción; Chile Fil: Pastore, Hernán. Administración de Parques Nacionales; Argentina. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - Patagonia Norte. Instituto de Investigaciones En Biodiversidad y Medioambiente. Subsede Junín de Los Andes-inibioma-centro de Ecología Aplicada del Neuquén (cean) | Universidad Nacional del Comahue. Centro Regional Universitario Bariloche. Instituto de Investigaciones En Biodiversidad y Medioambiente. Subsede Junín de Los Andes-inibioma-centro de Ecología Aplicada del Neuquén (cean).; Argentina Fil: Peñafiel Ricaurte, Alexandra. Universidad Andrés Bello; Chile Fil: Rojas Salinas, Leonora. División de Recursos Naturales y Biodiversidad; Chile Fil: Manuel Serrano, José. Universidad de Chile; Chile Fil: Sepúlveda, Maximiliano A.. Corporación Nacional Forestal Ministerio de Agricultura; Chile Fil: Toledo, Gisela Verónica. Fundación Huilo Huilo; Chile Fil: Úbeda, Carmen A.. Universidad Nacional del Comahue. Centro Regional Universitario Bariloche; Argentina Fil: Uribe Rivera, David E.. Organización No Gubernamental (ong) Ranita de Darwin; Chile Fil: Valdivia, Catalina. Universidad Andrés Bello; Chile Fil: Wren, Sally. University Of Otago; Nueva Zelanda Fil: Angulo, Ariadne. Iucn Ssc Amphibian Specialist Group; Canadá

Forest management can be used to increase the local abundance of species of conservation concern. To achieve this goal, managers must be sure that the relationships between the targeted forest attributes and the focal species abundance are based on robust data and inference. This is a critical issue as the same forest attributes could have opposing effects on species abundance and the detectability of individuals, impairing our ability to detect useful habitat quality surrogates and to provide correct forest management recommendations. Using spatially stratified capture-recapture models (a.k.a. multinomial N-mixture models), we evaluated the effects of stand-level forest attributes on detection probability and local abundance for the endangered Southern Darwin’s frog (Rhinoderma darwinii), a forest-specialist and fully terrestrial amphibian endemic to the South American temperate forest. Our results show that an increase of stand basal area and a decrease of daily microclimatic fluctuation (i.e. an increase in structural complexity) were positively associated with the local abundance of R. darwinii. These stand-level forest attributes also explained the among-population variation in detection probability, although the relationships were opposite to those for abundance. Consequently, an analysis of raw frog counts (i.e. not adjusted for imperfect detection) did not reveal all the factors associated with local abundance. Our results provide further support to previous claims that raw counts of individuals should not be used, generally, as a proxy of abundance in species inhabiting forest ecosystems and elsewhere. More importantly, the opposite effect of forest attributes on abundance and detectability observed in our study highlights the need to use methods that quantify species-habitat relationships in a robust way and which take habitat-specific imperfect detection into account.

Dispersal is a central process in ecology and evolution. It strongly influences the dynamics of spatially structured populations and affects evolutionary processes by shaping patterns of gene flow. For these reasons, dispersal has received considerable attention from ecologists, evolutionary biologists, and conservationists. Although it has been studied extensively in taxa such as birds and mammals, much less is known about dispersal in vertebrates with complex life cycles such as pond-breeding amphibians. Over the past two decades, researchers have taken an ever-increasing interest in amphibian dispersal and initiated both basic and applied studies, using a broad range of experimental and observational approaches. This body of research reveals complex dispersal patterns, causations, and syndromes, with dramatic consequences for the demography and genetics of amphibian populations. In this review, our goals are to: redefine and clarify the concept of amphibian dispersal; review current knowledge about the effects of individual (i.e., condition-dependent dispersal) and environmental (i.e., context-dependent dispersal) factors during the three stages of dispersal (i.e., emigration, transience, and immigration); identify the demographic and genetic consequences of dispersal in spatially structured amphibian populations; and propose new research avenues to extend our understanding of amphibian dispersal., Hugo Cayuela warmly thanks the Banting Postdoctoral Fellowships program for its financial support. Further-more, Mathieu Denoël is Research Director at Fonds dela Recherche Scientifique—FNRS. During manuscript writing, Andrés Valenzuela-Sánchez was supported bya FONDECYT de postdoctorado No. 3180107. Any useof trade, firm, and product names is for descriptive purposes only and does not imply endorsement by the U.S.Government. Íñigo Martínez-Solano acknowledges funding by FEDER/Ministerio de Ciencia, Innovación y Universidades—Agencia Estatal de Investigación, Spain,grant CGL2017-83131-P.

Emerging fungal diseases represent a threat to food security, animal and human health worldwide. Amphibian chytridiomycosis, caused by the fungus Batrachochytrium dendrobatidis (Bd), has been associated with catastrophic and well-documented amphibian population declines and extinctions. For the first time, Bd was cultured from native and non-native wild amphibians in Chile. Phylogenomic analyses revealed that Chilean isolates AVS2, AVS4 and AVS7 group within the global panzootic lineage of Bd (BdGPL) in a single highly supported clade that includes a genotype previously isolated from the United Kingdom. Our results extend the known distribution of BdGPL in South America and suggest a single and relatively recent introduction of BdGPL into the country, providing additional support to the role of anthropogenic activity in the global spread of this panzootic lineage.

Amphibian chytridiomycosis, due to infection with the fungus Batrachochytrium dendrobatidis (Bd), has been associated with the alarming decline and extinction crisis of amphibians worldwide. It is essential for conservation management to identify regions with high or low suitability for Bd. We use a species distribution model to estimate the environmental suitability of Bd in the Chilean Winter Rainfall - Valdivian Forest biodiversity hotspot. Fourteen environmental variables were used as predictors in the statistical modelling (Maxent, generalized linear models, random forest) which also included 56 independent Bd+ localities. High risk-areas (i.e., suitability above a defined threshold) were validated through prospective field surveys conducted in 2017. As results from Maxent, which only uses presence data, were the only results retained, refugia (i.e., suitability below a defined threshold) were validated with the Bd absences (N = 12) used in the GLM and RF modelling. Our results showed that: (i) suitability for Bd increased with human footprint and with shorter distances to urban centres and water bodies and decreased with elevation; (ii) climate was not a major factor shaping the current distribution of Bd; and (iii) the model predicted high-risk and refugia areas fairly well. Surveys of 24 new localities in high-risk areas confirmed that 23 were Bd+, hence these areas warrant consideration for long-term Bd surveillance, population monitoring and disease mitigation. In addition, five localities with apparent Bd absence were found in the predicted high-risk areas. Our models showed that refugia can exist near high risk areas and Bd+ sites. Four localities with apparent Bd absence were located within the refugia predicted by the model. Preventing Bd transmission to such refugia is of paramount importance for persistence of Bd susceptible amphibian populations. The identification and validation through prospective field surveys of high-risk areas and refugia is imperative to develop strategies to prevent further arrival and establishment of Bd. Also, by identifying amphibian species or populations of conservation concern in such areas, will help to guide specific actions to reduce the biodiversity loss caused by chytridiomycosis.

International audience; Dispersal is a key process in ecology and evolution. Both theoretical and empirical evidence in actively dispersing organisms support the general notion that the use of nearly straight dispersal paths is a highly ef␣cient way to maximize dispersal success in heterogenous landscapes. In homogeneous landscapes, in contrast, the bene␣ts of a straighter dispersal path could be outweighed by an increase in risk costs, favouring the evolution of tortuous dispersal paths resulting in a relatively slow dispersal. Empirical support for this theoretical prediction, however, has remained elusive. To explore this theoretical pre- diction, we studied the movement behaviour of the southern Darwin's frog, Rhinoderma darwinii, a fully terrestrial amphibian inhabiting a highly homogeneous environment (i.e. South American temperate forest). Using spatial captureerecapture data collected over a 4-year period in wild populations, in combination with statistical and simulation modelling, we found evidence of a slow natal dispersal lasting one year or more. In contrast, adults exhibited high site ␣delity, having a median annual displacement of 3.64 m. A correlated random walk model produced synthetic distributions of juvenile annual displacement that were nearly identical to the empirical data, suggesting that a plausible explanation of juvenile dispersal is the use of routine movements (with high path tortuosity) over short temporal scales (

Parasitic chytrid fungi have emerged as a significant threat to amphibian species worldwide, necessitating the development of techniques to isolate these pathogens into sterile culture for research purposes. However, early methods of isolating chytrids from their hosts relied on killing amphibians. We modified a pre-existing protocol for isolating chytrids from infected animals to use toe clips and biopsies from toe webbing rather than euthanizing hosts, and distributed the protocol to interested researchers worldwide as part of the BiodivERsA project RACE – here called the RML protocol. In tandem, we developed a lethal procedure for isolating chytrids from tadpole mouthparts. Reviewing a database of use a decade after their inception, we find that these methods have been widely applied across at least 5 continents, 23 countries and in 62 amphibian species, and have been successfully used to isolate chytrids in remote field locations. Isolation of chytrids by the non-lethal RML protocol occured in 18% of attempts with 207 fungal isolates and three species of chytrid being recovered. Isolation of chytrids from tadpoles occured in 43% of attempts with 334 fungal isolates of one species (Batrachochytrium dendrobatidis) being recovered. Together, these methods have resulted in a significant reduction and refinement of our use of threatened amphibian species and have improved our ability to work with this important group of emerging fungal pathogens.

Amphibians are hosts for a wide variety of micro- and macro-parasites. Chigger mites from the Hannemania genus are known to infect a wide variety of amphibian species across the Americas. In Chile, three species (H. pattoni, H. gonzaleacunae and H. ortizi) have been described infecting native anurans; however, neither impacts nor the microscopic lesions associated with these parasites have been described. Here, we document 70% prevalence of chigger mite infection in Eupsophus roseus and absence of infection in Rhinoderma darwinii in the Nahuelbuta Range, Chile. Additionally, we describe the macroscopic and microscopic lesions produced by H. ortizi in one of these species, documenting previously undescribed lesions (granulomatous myositis) within the host's musculature. These findings highlight that further research to better understand the impacts of chigger mite infection on amphibians is urgently required in Chile and elsewhere.

Indexación: Web of Science; Scopus. Climate change is a major threat to biodiversity; the development of models that reliably predict its effects on species distributions is a priority for conservation biogeography. Two of the main issues for accurate temporal predictions from Species Distribution Models (SDM) are model extrapolation and unrealistic dispersal scenarios. We assessed the consequences of these issues on the accuracy of climate-driven SDM predictions for the dispersal-limited Darwin's frog Rhinoderma darwinii in South America. We calibrated models using historical data (1950-1975) and projected them across 40 yr to predict distribution under current climatic conditions, assessing predictive accuracy through the area under the ROC curve (AUC) and True Skill Statistics (TSS), contrasting binary model predictions against temporal-independent validation data set (i.e., current presences/absences). To assess the effects of incorporating dispersal processes we compared the predictive accuracy of dispersal constrained models with no dispersal limited SDMs; and to assess the effects of model extrapolation on the predictive accuracy of SDMs, we compared this between extrapolated and no extrapolated areas. The incorporation of dispersal processes enhanced predictive accuracy, mainly due to a decrease in the false presence rate of model predictions, which is consistent with discrimination of suitable but inaccessible habitat. This also had consequences on range size changes over time, which is the most used proxy for extinction risk from climate change. The area of current climatic conditions that was absent in the baseline conditions (i.e., extrapolated areas) represents 39% of the study area, leading to a significant decrease in predictive accuracy of model predictions for those areas. Our results highlight (1) incorporating dispersal processes can improve predictive accuracy of temporal transference of SDMs and reduce uncertainties of extinction risk assessments from global change; (2) as geographical areas subjected to novel climates are expected to arise, they must be reported as they show less accurate predictions under future climate scenarios. Consequently, environmental extrapolation and dispersal processes should be explicitly incorporated to report and reduce uncertainties in temporal predictions of SDMs, respectively. Doing so, we expect to improve the reliability of the information we provide for conservation decision makers under future climate change scenarios. http://onlinelibrary.wiley.com/doi/10.1002/eap.1556/abstract;jsessionid=1E2084FF99600D0EEC9FA358A3DBC2A3.f02t01

The decline of wildlife populations due to emerging infectious disease often shows a common pattern: the parasite invades a naive host population, producing epidemic disease and a population decline, sometimes with extirpation. Some susceptible host populations can survive the epidemic phase and persist with endemic parasitic infection. Understanding host–parasite dynamics leading to persistence of the system is imperative to adequately inform conservation practice. Here we combine field data, statistical and mathematical modelling to explore the dynamics of the apparently stable Rhinoderma darwinii – Batrachochytrium dendrobatidis (Bd) system. Our results indicate that Bd-induced population extirpation may occur even in the absence of epidemics and where parasite prevalence is relatively low. These empirical findings are consistent with previous theoretical predictions showing that highly pathogenic parasites are able to regulate host populations even at extremely low prevalence, highlighting that disease threats should be investigated as a cause of population declines even in the absence of an overt increase in mortality.