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The successful implementation of the Convention on Biological Diversity’s post-2020Global Biodiversity Framework will rely on effective translation of targets from global tonational level and increased engagement across diverse sectors of society. Species conserva-tion targets require policy support measures that can be applied to a diversity of taxonomicgroups, that link action targets to outcome goals, and that can be applied to both global andnational data sets to account for national context, which the species threat abatement andrestoration (STAR) metric does. To test the flexibility of STAR, we applied the metric to vascular plants listed on national red lists of Brazil, Norway, and South Africa. The STARmetric uses data on species’ extinction risk, distributions, and threats, which we obtainedfrom national red lists to quantify the contribution that threat abatement and habitatrestoration activities could make to reducing species’ extinction risk. Across all 3 coun-tries, the greatest opportunity for reducing plant species’ extinction risk was from abatingthreats from agricultural activities, which could reduce species’ extinction risk by 54% inNorway, 36% in South Africa, and 29% in Brazil. Species extinction risk could be reducedby a further 21% in South Africa by abating threats from invasive species and by 21% inBrazil by abating threats from urban expansion. Even with different approaches to red-listing among countries, the STAR metric yielded informative results that identified wherethe greatest conservation gains could be made for species through threat-abatement andrestoration activities. Quantifiably linking local taxonomic coverage and data collection toglobal processes with STAR would allow national target setting to align with global targetsand enable state and nonstate actors to measure and report on their potential contributionsto species conservation. habitat restoration, national red lists, species’ extinction risk, threat reduction, threatened species, vascular plants

The skin microbiome is an important part of amphibian immune defenses and protects against pathogens such as the chytrid fungus Batrachochytrium dendrobatidis (Bd), which causes the skin disease chytridiomycosis. Alteration of the microbiome by anthropogenic factors, like pesticides, can impact this protective trait, disrupting its functionality. Chlorothalonil is a widely used fungicide that has been recognized as having an impact on amphibians, but so far, no studies have investigated its effects on amphibian microbial communities. In the present study, we used the amphibian Lithobates vibicarius from the montane forest of Costa Rica, which now appears to persist despite ongoing Bd-exposure, as an experimental model organism. We used 16S rRNA amplicon sequencing to investigate the effect of chlorothalonil on tadpoles’ skin microbiome. We found that exposure to chlorothalonil changes bacterial community composition, with more significant changes at a higher concentration. We also found that a larger number of bacteria were reduced on tadpoles’ skin when exposed to the higher concentration of chlorothalonil. We detected four presumed Bd-inhibitory bacteria being suppressed on tadpoles exposed to the fungicide. Our results suggest that exposure to a widely used fungicide could be impacting host-associated bacterial communities, potentially disrupting an amphibian protective trait against pathogens.

Mucosal defenses are crucial in animals for protection against pathogens and predators. Host defense peptides (antimicrobial peptides, AMPs) as well as skin-associated microbes are key components of mucosal immunity, particularly in amphibians. We integrate microbiology, molecular biology, network-thinking, and proteomics to understand how host and microbially derived products on amphibian skin (referred to as the mucosome) serve as pathogen defenses. We studied defense mechanisms against chytrid pathogens

RESUMEN Examinamos los factores que influyen en la selección de presas por perros callejeros en el humedal Estero Culebrón (Coquimbo, Chile) y caracterizamos sus ataques durante 20 visitas en el año 2015. Utilizamos modelos lineales generalizados considerando el tamaño del ave, su abundancia relativa, el sitio y tipo de sustrato como variables explicativas. Registramos una jauría de siete individuos que realizaron 34 ataques sobre aves, de las cuales el pelícano presentó la mayor frecuencia de predación. El tamaño del ave y el sitio se relacionaron positivamente con los ataques. La selección del pelícano como presa podría estar relacionada con su baja distancia de inicio de vuelo y su gran tamaño, lo que facilitaría el ataque de los perros y, además, este mayor tamaño podría sostener energéticamente a la jauría, especialmente cuando es numerosa. Otras condiciones como la ausencia de totora (Typha angustipholia) y la baja profundidad del agua en el sector playa, facilitarían el desarrollo de los ataques al reducir los obstáculos a la persecución. Por último, debido al peligro que representan estos animales para las personas y la fauna de los humedales, es urgente desarrollar planes de manejo que consideren su retiro y traslado a centros de rescate, así como de implementar campañas de esterilización y educación.

Mamey sapote is a fruit rich in specific keto-carotenoids, namely sapotexanthin and cryptocapsin. Their chemical structure suggests their provitamin A activity, although their absorption and conversion to vitamin A remained to be demonstrated in humans. Besides structure-related factors, the fruit matrix might also hamper absorption and conversion efficiency. Therefore, we monitored carotenoid and vitamin A levels in triacylglycerol-rich lipoprotein (TRL) fractions in plasma of human participants after consumption of fresh sapote and a carotenoid-rich “matrix-free” formulation derived thereof. A randomized 2-way cross-over study was conducted to compare the post-prandial bioavailability of 0.8 mg sapotexanthin and 1.2–1.5 mg cryptocapsin from the above-mentioned test meals. Seven blood samples were drawn over 9.5 h after test meal consumption. Carotenoids and retinoids were quantitated in TRL fractions using HPLC-DAD. Sapotexanthin was absorbed by all participants from all meals, being ca. 36% more bioavailable from the “matrix-free” formulation (AUCmedian = 73.4 nmol∙h/L) than from the fresh fruit (AUCmedian = 54.0 nmol∙h/L; p ≤ 0.001). Cryptocapsin was only absorbed by 4 of 13 participants. The appearance of retinyl esters was observed in all participants independent of the test meal. Although the fruit matrix hampered carotenoid in vivo-bioavailability from sapote, the fruit clearly represents a valuable source of vitamin A for humans. German Academic Exchange Service/[]/DAAD/Alemania UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Agroalimentarias::Centro Nacional de Ciencia y Tecnología de Alimentos (CITA) UCR::Vicerrectoría de Docencia::Ciencias Agroalimentarias::Facultad de Ciencias Agroalimentarias::Escuela de Tecnología de Alimentos UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Agroalimentarias::Centro de Investigación en Nutrición Animal (CINA) UCR::Vicerrectoría de Docencia::Salud::Facultad de Medicina::Escuela de Medicina

In this study, the effect of four anaesthetic protocols that included the combination of xylazine (X) and ketamine (K) with acepromazine (A) and opioids (methadone (Me), morphine (Mo) or tramadol (T)) was evaluated in laboratory rats of both sexes. Ultrasonic vocalization (USV) was used as an indicator of pain during the recovery period. The objective was to evaluate the physiological parameters and the analgesic effect of each protocol to determine which protocol was the safest and fulfil the requirements of a balanced anaesthesia. The better protocols were the XKA protocol for both sexes and the XKMe protocol for females because the combinations achieve surgical plane of anaesthesia in rats. However, pain assessment during the formalin test revealed that rats anaesthetized with XKA produced more numbers of USV, suggesting that it is not a good protocol for the control of immediate postoperative pain. All protocols produced depression in body temperature and respiratory and heart rates, and had important effects, such as micturition and maintenance of open eyes. Only rats anaesthetized with XKA protocol did not present piloerection. These results demonstrated that good monitoring and care during anaesthesia must be included to prevent complications that compromise the life of the animal and to ensure a good recovery. The inclusion of analgesia in anaesthesia protocols must be used routinely, ensuring minimal presence of pain and thus more reliable results in the experimental procedures.

Amphibians are globally threatened by emerging infectious diseases, and ranaviruses are among the most concerning pathogens to threaten species in the wild. We sampled for ranaviruses in wild amphibians at 8 sites in Costa Rica, spanning broad climatic zones and taxonomic associations. Seven of these sites are inhabited by highly threatened amphibian species that persist at low global population sizes after population declines due to amphibian chytridiomycosis. One of the surveyed sites is occupied by an introduced amphibian species, which is relatively rare in Central America but may be an important pathway for long-distance transport of ranaviruses. We detected ranavirus using quantitative polymerase chain reaction in 16.3% of the 243 individuals and among 5 of our 8 sites, but not at the site with the introduced species. Infection prevalence varied among species and sites, but not with mean annual temperature or mean annual precipitation. Infection intensity did not vary with species, site, temperature, or precipitation. Our results show that ranavirus infection is spatially widespread in Costa Rica, affecting a broad range of host species, and occurs across climatic zones—though we encountered no mortality or morbidity in our sampled species. Ranaviruses are known to cause intermittent mass mortality in amphibian populations, and the threatened species sampled here are likely vulnerable to population impacts from emerging ranaviruses. Therefore, we believe the potential impacts of ranaviruses on amphibian populations in tropical regions have likely been underestimated, and that they should be viewed as a potential major stressor to threatened amphibians in tropical regions.

Recent research in humans, livestock, and wildlife using high-throughput next-generation sequencing (NGS) has identified that resident microbiota play an essential role in disease resistance, host health, and adaptation to biotic and abiotic stressors. Since amphibians are currently facing population declines and extinctions attributable to anthropogenic pressures and emerging diseases, an understanding of the effects of microbiome dysbiosis and mitigation is a prerequisite for amphibian conservation and disease management. Interest is now growing with regard to understanding the influence of unfavorable environmental conditions on the amphibian microbiome and the effects of dysbiosis on the susceptibility to pathogenic infections. Here, we summarize information on the amphibian microbiome, specifically concerning intrinsic and extrinsic factors that shape the skin and gut microbiome. We explore diverse types of unfavorable environmental perturbations and the ways in which they can impact the microbiota of an individual so that we can better comprehend the consequences of stressors and dysbiosis on pathogen emergence and health. We discuss the role of the microbiome in amphibian conservation and identify gaps of knowledge that need to be filled if we are to achieve a meta-organism conservation approach. NGS studies should be complemented with other high-throughput “-omic” approaches to target microbiome functionality. Understanding the microbiome might be the missing piece in the overall strategy that will help maintain the health of amphibians in a world with highly affected environments and that will prevent/mitigate emerging infectious diseases.

We report the rediscovery of a declared extinct frog,Craugastor escoces, at the edge of a protected forest in the Juan Castro Blanco National Park, Alajuela, Costa Rica. This species, which is endemic to Costa Rica, had not been observed since 1986. The rediscovery of this species comes after 30 years without being seen and 12 years of being declared extinct. The site where we found the species is located in the west of the central mountain region of Costa Rica, which is >15 km away from its known distribution. Our finding adds another species to the list of the few rediscovered frogs declared extinct. Knowing thatC. escocescan still be found triggers the need for conservation strategies to help the species survive.

Amphibian populations are globally threatened by emerging infectious diseases, and 2 pathogens in particular are recognized as major threats: the amphibian chytrid fungus Batra- chochytrium dendrobatidis (Bd) and ranaviruses. Here, we evaluated the prevalence of infection by Bd and ranavirus in an assemblage of frogs from a lowland wet forest in Costa Rica. We found an overall prevalence of 21.3% for Bd and 16.6% for ranavirus, and detected both pathogens widely among our 20 sampled species. We found a positive association between ranavirus and Bd infection in one of our 4 most commonly sampled species. We also found a positive but non-significant asso- ciation be tween infection by ranavirus and infection by Bd among species overall. Our study is among the first detailed evaluations of ranavirus prevalence in the American tropics, and to our knowledge is the first to detect a positive association between Bd and ranavirus in any species. Considerable research attention has focused on the ecology of Bd in tropical regions, yet we argue that greater research focus is necessary to understand the ecology and conservation impact of ranaviruses on amphibian populations already decimated by the emergence of Bd.

Most animals metamorphose, changing morphology, physiology, behavior and ecological interactions. Size- and habitat-dependent mortality risk is thought to affect the evolution and plastic expression of metamorphic timing, and high predation during the morphological transition is posited as a critical selective force shaping complex life cycles. Nonetheless, empirical data on how risk changes across metamorphosis and stage-specific habitats, or how that varies with size, are rare. We examined predator–prey interactions of red-eyed treefrogs, Agalychnis callidryas, with an aquatic predator (giant water bug, Belostoma) and a semi-terrestrial predator (fishing spider, Thaumasia) across metamorphosis. We manipulated tadpole density to generate variation in metamorph size and conducted predation trials at multiple developmental stages. We quantified how frog behavior (activity) changes across metamorphic development, habitats, and predator presence or absence. In aquatic trials with water bugs, frog mortality increased with forelimb emergence, as hypothesized. In semi-terrestrial trials, contrary to predictions, predation by spiders increased, not decreased, with tail resorption. In neither case did frog size affect mortality. Frogs reduced activity upon forelimb emergence in the water, and further with emergence into air, then increased activity with tail resorption. Longer-tailed metamorphs were captured more often in spider attacks, but attacked less, as most attacks followed prey movements. Metamorphs behaviorally compensated for poor escape performance more effectively on land than in water, thus emergence timing may critically affect mortality. The developmental timing of the ecological transition between environments that select for different larval and juvenile phenotypes is an important, neglected variable in studies of complex life cycles.

Use of food and spatial resources by two frogs of the genus Dendropsophus (Anura: Hylidae) from La Selva, Costa Rica. Differences in the use of resources by similar species have been related to a reduction in the interspecific competition that allows coexistence. Also, other factors, such as high availability of resources in the environment, vegetation structure, environmental heterogeneity, reproductive modes, and predation, can influence the use of resources and favor coexistence. We studied the use of space and food resources by males of two species of hylid frogs, Dendropsophus ebraccatus and D. phlebodes, in two swamps in the Neotropical lowland forest at La Selva Biological Station, Costa Rica. We determined space and food use by characterizing calling sites and the diet of the frogs by stomach flushing. Males call from different substrates, and use different sizes of leaves and perch heights. Both species seem to be feeding generalists. Their diets are similar and indicate a moderate trophic niche overlap based on the type of prey consumed. Many males of both species had empty stomachs, suggesting that food resources are not an important factor affecting the coexistence of these species. Our study also indicates a lack of competitive interactions for space and food resources, and suggests that the abundant and structurally diverse vegetation provides many different vocalization sites for the male frogs and fosters coexistence of these species during the breeding season at La Selva.