Anticoagulant rodenticides (ARs) are indiscriminate toxicants that threaten nontarget predatory and scavenger species through secondary poisoning. Accumulating evidence suggests that AR exposure may have disruptive sublethal consequences on individuals that can affect fitness. We evaluated AR-related effects on genome-wide expression patterns in a population of bobcats in southern California. We identify differential expression of genes involved in xenobiotic metabolism, endoplasmic reticulum stress response, epithelial integrity and both adaptive and innate immune function. Further, we find that differential expression of immune-related genes may be attributable to AR-related effects on leucocyte differentiation. Collectively, our results provide an unprecedented understanding of the sublethal effects of AR exposure on a wild carnivore. These findings highlight potential detrimental effects of ARs on a wide variety of species worldwide that may consume poisoned rodents and indicate the need to investigate gene expression effects of other toxicants added to natural environments by humans.

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This study was conceived to detect skin mites in social mammals through real-time qPCR, and to estimate taxonomic Demodex and further Prostigmata mite relationships in different host species by comparing sequences from two genes: mitochondrial 16S rRNA and nuclear 18S rRNA. We determined the mite prevalence in the hair follicles of marmots (13%) and bats (17%). The high prevalence found in marmots and bats by sampling only one site on the body may indicate that mites are common inhabitants of their skin. Since we found three different mites (Neuchelacheles sp, Myobia sp and Penthaleus sp) in three bat species (Miotis yumanensis, Miotis californicus and Corynorhinus townsendii) and two different mites (both inferred to be members of the Prostigmata order) in one marmot species (Marmota flaviventris), we tentatively concluded that these skin mites 1) cannot be assigned to the same genus based only on a common host, and 2) seem to evolve according to the specific habitat and/or specific hair and sebaceous gland of the mammalian host. Moreover, two M. yumanensis bats harbored identical Neuchelacheles mites, indicating the possibility of interspecific cross-infection within a colony. However, some skin mites species are less restricted by host species than previously thought. Specifically, Demodex canis seems to be more transmissible across species than other skin mites. D. canis have been found mostly in dogs but also in cats and captive bats. In addition, we report the first case of D. canis infestation in a domestic ferret (Mustela putorius). All these mammalian hosts are related to human activities, and D. canis evolution may be a consequence of this relationship. The monophyletic Demodex clade showing closely related dog and human Demodex sequences also supports this likely hypothesis.

Although oceans provide critical ecosystem services and support the most abundant populations on earth, the extent of damage impacting oceans and the diversity of strategies to protect them is disconcertingly, and disproportionately, understudied. While conventional modes of conservation have made strides in mitigating impacts of human activities on ocean ecosystems, those strategies alone cannot completely stem the tide of mounting threats. Biotechnology and genomic research should be harnessed and developed within conservation frameworks to foster the persistence of viable ocean ecosystems. This document distills the results of a targeted survey, the Ocean Genomics Horizon Scan, which assessed opportunities to bring novel genetic rescue tools to marine conservation. From this Horizon Scan, we have identified how novel approaches from synthetic biology and genomics can alleviate major marine threats. While ethical frameworks for biotechnological interventions are necessary for effective and responsible practice, here we primarily assessed technological and social factors directly affecting technical development and deployment of biotechnology interventions for marine conservation. Genetic insight can greatly enhance established conservation methods, but the severity of many threats may demand genomic intervention. While intervention is controversial, for many marine areas the cost of inaction is too high to allow controversy to be a barrier to conserving viable ecosystems. Here, we offer a set of recommendations for engagement and program development to deploy genetic rescue safely and responsibly.

Recently emerged wildlife diseases that threaten population-or species-level persistence have forced conservation biologists to direct their attention toward disease processes, including transmission dynamics and host responses to pathogen exposure (Daszak

Human activities threaten wildlife with a variety of novel stressors such as exposure to toxicants. Anticoagulant rodenticides (ARs) are toxicants applied worldwide and through bioaccumulation, threaten species that prey on poisoned rodents or their predators. We studied a population of urban bobcats in southern California that declined rapidly from 2002-2005 due to notoedric mange. We first assessed prevalence of AR exposure using blood and liver samples across the population and found widespread exposure (>90%). Death associated with mange was strongly correlated with cumulative first-and second-generation AR exposure. These findings suggested that exposure to both first-and second-generation ARs were an underlying cause of the disease. We next aimed to understand the sublethal immunological and physiological effects of AR exposure in this natural population. We used two approaches: 1) we used a comprehensive suite of health assays (complete blood counts, blood chemistry assessment, and immunological profiling), and 2) we quantified AR-induced differential gene expression in blood for a subset of individuals. We found that sublethal AR exposure, primarily measured as exposure to diphacinone, is associated with hallmark indicators of generalized systemic inflammation that in persistence could promote immune dysfunction. Further, differential gene expression findings supported the results of immunological profiling. Further, a decrease in the expression of genes associated with epithelial maintenance simultaneous to a decrease in gene expression linked with ectoparasitic immune response may explain the link between AR exposure and mange vulnerability. Such indirect effects of sublethal exposure exemplify the challenge of protecting wild populations from common toxicants in human-dominated environments.