Climate change-induced extinctions are estimated to eliminate one in six known species by the end of the century. One major factor that will contribute to these extinctions is extreme climatic events. Here, we show the ecological impacts of recent record warm air temperatures and simultaneous peak drought conditions in California. From 2008-2016, the southern populations of a wide-ranging endemic amphibian (the California newt, Taricha torosa) showed a 20% reduction to mean body condition and significant losses to variation in body condition linked with extreme climate deviations. However, body condition in northern populations remained relatively unaffected during this period. Range-wide population estimates of change to body condition under future climate change scenarios within the next 50 years suggest that northern populations will mirror the loss of body condition recently observed in southern populations. This change is predicated on latter 21 st century climate deviations that resemble recent conditions in Southern California. Thus, the ecological consequences of climate change have already occurred across the warmer, drier regions of Southern California, and our results suggest that predicted climate vulnerable regions in the more mesic northern range likely will not provide climate refuge for numerous amphibian communities.

No abstract

Background Horses are host to a plethora of parasites. Knowledge of the seasonality of parasite egg shedding and transmission is important for constructing parasite control programs. However, studies describing these patterns are sparse, and have largely been conducted only in the United Kingdom. This study evaluated strongylid egg shedding patterns and transmission dynamics of Strongylus vulgaris in naturally infected and untreated mares and foals through one calendar year in Kentucky, USA. The study also investigated the existence of a peri-parturient rise (PPR) in strongylid egg counts in foaling mares and collected information about Strongyloides westeri and Parascaris spp. in the foals. Methods This study was conducted from January to December 2018. A herd of 18 mares, one stallion, and 14 foals born in 2018 were followed throughout the year. Sera and feces were collected biweekly from all horses, and worm burdens enumerated in 13 foals at necropsy. An S. vulgaris ELISA antibody test was run on all serum samples. Fecal egg counts were determined for all horses, and coproculture and qPCR assay were employed to test for the presence of S. vulgaris in the mature horses. Data were analyzed using the proc glimmix procedure in the SAS 9.4 software program. Results We found a general lack of seasonality in strongylid egg shedding throughout the year among the mature horses, and no PPR was demonstrated. Shedding of S. vulgaris eggs displayed a higher abundance during the spring, but findings were variable and not statistically significant. Anti-S. vulgaris antibody concentrations did not display significant fluctuations in the mature horses, but evidence of passive transfer of antibodies to the foals was demonstrated, and foals assumed their own production of antibodies starting at approximately 20 weeks of age. Overall, colts shed higher numbers of strongylid, ascarid, and S. westeri eggs than fillies. Conclusions This study demonstrated a lack of seasonality in strongylid egg shedding for the study population, which is in stark contrast to previous studies conducted elsewhere. This strongly suggests that more studies should be done investigating these patterns under different climatic conditions. Graphical Abstract

As the global number of endangered, rare, and invasive species continues to increase, legally mandated efforts to monitor species’ ranges and abundances have grown exponentially. Human population growth is affecting an increasing number of species that need to be monitored, resulting in difficulties providing necessary data on the abundances, ranges, and movement of these species (Kelly 2014). We currently lack practical monitoring techniques for remote, hard-to-access habitats and species with low population counts, which makes it difficult to make informed management decisions (Kelly et al. 2014). Biologists use a variety of comprehensive field- and labor-based monitoring techniques including mark-recapture studies, depletion surveys, and tracking surveys. Environmental DNA (eDNA) is the genetic material shed by every organism into its surrounding environment, which can then be collected from air, soil, or water and analyzed to assess the composition of species present at a site (Thomsen and Willerslev 2015). eDNA monitoring is a tool that does not require the same man-hours that other techniques require. This allows eDNA to be deployed for biomonitoring, natural resource management, and decision making in ways traditional techniques cannot (Biggs et al. 2015; Kelly et al. 2014). Past use of eDNA in programs, including CaleDNA and the Aquatic eDNA atlas project, demonstrated that eDNA is currently a viable monitoring tool for endangered, rare, cryptic, and invasive species. In 2020, the United States Department of the Interior’s National Invasive Species Council Work Plan recognized the potential of eDNA and prioritized its exploration for the first time (United States Department of the Interior, 2020). We believe developing permanent funding sources or amending AB 2470 to include funds for natural resource managers to implement eDNA monitoring programs and information databases is necessary to continue to support societal growth and biodiversity in California. An eDNA monitoring program will allow natural resource managers to better inform land development, conservation, and environmental management decision-making in California.

Extreme weather events are predicted to increase as a result of climate change, yet amphibian responses to extreme disturbance events remain understudied, especially in the Neotropics. Recently, an unprecedented windstorm within a protected Costa Rican rainforest opened large light gaps in sites where we have studied behavioral responses of diurnal strawberry poison frogs (Oophaga pumilio) to ultraviolet radiation for nearly two decades. Previous studies demonstrate that O. pumilio selects and defends perches where ultraviolet radiation (UV-B) is relatively low, likely because of the lethal and sublethal effects of UV-B. In this natural experiment, we quantified disturbance to O. pumilio habitat, surveyed for the presence of O. pumilio in both high-disturbance and low-disturbance areas of the forest, and assessed UV-B levelsand perch selection behavior in both disturbance levels. Fewer frogs were detected in high-disturbance habitat than in low-disturbance habitat. In general, frogs were found vocalizing at perches in both disturbance levels, and in both cases, in significantly lower UV-B levels relative to ambient adjacent surroundings. However, frogs at perches in high-disturbance areas were exposed to UV-B levels nearly 10 times greater than males at perches in low-disturbance areas. Thus, behavioral avoidance of UV-B may not reduce the risks associated with elevated exposure under these novel conditions, and similarly, if future climate and human-driven land-use change lead to sustained analogous environments.