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Peninsular bighorn sheep (Ovis canadensis nelsoni) are found exclusively in Southern California and Baja Mexico. They are federally endangered due to multiple threats, including introduced infectious disease. From 1981 - 2017, we conducted surveillance for 16 pathogens and estimated population sizes, adult survival, and lamb survival. We used mixed effects regression models to assess disease patterns at the individual and population levels. Pathogen infection/exposure prevalence varied both spatially and temporally. Our findings indicate that the primary predictor of individual pathogen infection/exposure was the region in which an animal was captured, implying that transmission is driven by local ecological or behavioral factors. Higher Mycoplasma ovipneumoniae seropositivity was associated with lower lamb survival, consistent with lambs having high rates of pneumonia-associated mortality, which may be slowing population recovery. There was no association between M. ovipneumoniae and adult survival. Adult survival was positively associated with population size and parainfluenza-3 virus seroprevalence in the same year, and orf virus seroprevalence in the previous year. Peninsular bighorn sheep are recovering from small population sizes in a habitat of environmental extremes, compounded by infectious disease. Our research can help inform future pathogen surveillance and population monitoring for the long-term conservation of this population.

The ability to rapidly detect and respond to wildlife morbidity and mortality events is critical for reducing threats to wildlife populations. Surveillance systems that use pre-diagnostic clinical data can contribute to the early detection of wildlife morbidities caused by a multitude of threats, including disease and anthropogenic disturbances. Here, we demonstrate proof of concept for use of a wildlife disease surveillance system, the 'Wildlife Morbidity and Mortality Event Alert System', that integrates pre-diagnostic clinical data in near real-time from a network of wildlife rehabilitation organizations, for early and enhanced detection of unusual wildlife morbidity and mortality events. The system classifies clinical pre-diagnostic data into relevant clinical classifications based on a natural language processing algorithm, generating alerts when more than the expected number of cases is recorded across the rehabilitation network. We demonstrated the effectiveness and efficiency of the system in alerting to events associated with both common and emerging diseases. Tapping into this readily available unconventional general surveillance data stream offers added value to existing wildlife disease surveillance programmes through a relatively efficient, low-cost strategy for the early detection of threats.

The effects of season, location, species, and sex on body weight and a comprehensive array of blood chemistry and hematology analytes were compared for free-ranging western (Aechmophorus occidentalis) and Clark's (Aechmophorus clarkii) grebes. Birds (n = 56) were collected from Puget Sound, WA, and Monterey Bay and San Francisco Bay, CA, from February 2007 to March 2011. The data supported generalization of observed ranges for most analytes across Aechmophorus grebe metapopulations wintering on the Pacific coast. Notable seasonal and location effects were observed for packed cell volume (winter 6% greater than fall; winter California [CA] 5% greater than Washington [WA]), total white blood cell count (CA 3.57 × 103 cells/µL greater than WA), heterophils (WA 10% greater than CA), lymphocytes (winter 19% greater than fall), heterophil to lymphocyte ratio (fall 5.7 greater than winter), basophils (CA greater than WA), plasma protein (WA about 10 g/L [1.0 g/dL] greater than CA), plasma protein to fibrinogen ratio (winter about 15 greater than fall), potassium (CA 2 mmol/L greater than WA), and liver enzymes (alanine aminotransferase, aspartate aminotransferase, lactate dehydrogenase: WA greater than CA). Within California, season had a greater effect on body mass than sex (mean winter weights about 200 g greater than fall), whereas within a season, males weighed only about 80 g more than females, on average. These data give biologists and veterinarians quantitative reference values to better assess health at the individual and metapopulation level.

Oil spills are environmental disasters and their long-term impact is not just a concern for the environment and economy, but also for first responders' health and wellbeing. Wildlife, such as aquatic birds and certain marine mammals, are highly susceptible to physiological effects of oiling, and oiled wildlife responders are crucial to provide measures for their survival. The purpose of this research was to explore the experiences of oiled wildlife responders and what factors and conditions have helped or inhibited the responders to care-affected wildlife. This study collected responses (n = 50) from a survey of responders who attended either the New Zealand MV Rena or US Refugio pipeline oil spills. Study participants were mostly older (>40), highly educated females. We found there were significant differences in compassion satisfaction, resilience, burnout and overall satisfaction based on age, gender and role. While most responders have only attended limited numbers of oil spill incidents, they reported positive experiences and found it rewarding. Findings from responders indicated that to lessen stress and compassion fatigue during an incident, provision of training and support from professional organizations equips responders with knowledge and skills that can support their personal resilience to respond to disaster events.

Sublethal effects of oil spills may dampen seabird rehabilitation success due to lingering negative impacts of contamination and stress on reproduction and long-term survival. These effects can be difficult to measure while birds are in care as well as once birds are released. Expression of sexually selected traits that are sensitive to condition can provide information on physiological status of birds. We evaluated plumage molt and gular pouch skin color of California brown pelicans (Pelecanus occidentalis californicus) following oil contamination and rehabilitation to test for differences between previously oiled and rehabilitated (post-spill) and presumably uncontaminated pelicans. Post-spill pelicans released with either color leg bands alone, or bands plus harness-mounted satellite GPS tags, were relocated and visually assessed in the field at non-breeding communal roosts and compared to surrounding unmarked pelicans in the general population. Non-oiled pelicans bearing GPS tags were also included in the study. Post-spill pelicans lagged the general population in molt of ornamental yellow crown feathers but hind neck transition into white plumage was not significantly different. Both post-spill and non-oiled pelicans wearing GPS tags had lower gular redness scores than the unmarked, non-oiled population. Pre-breeding gular pouch redness of post-spill pelicans was more strongly influenced by wearing of a GPS tag than a history of oil contamination and rehabilitation. Gular pouch redness of post-spill pelicans in the first 18 months after release was positively correlated with long term survivorship. If gular pouch color is a condition-dependent sexual signal and overall health influences plumage molt progression, our results indicate that many post-spill pelicans marked with bands alone were in relatively good condition going into the next breeding season, but those released with electronic tags experienced additional stress due to wearing the equipment, introducing a confounding variable to the post-release study.

Sub-lethal effects of oil spills may dampen seabird rehabilitation success due to lingering negative impacts of contamination and stress on reproduction and long-term survival. These effects can be difficult to measure while birds are in care as well as once released. Expression of sexually selected traits sensitive to condition can provide information on physiological status of birds. We evaluated plumage molt and gular pouch skin color of California brown pelicans (Pelecanus occidentalis californicus) following oil contamination and rehabilitation for differences between oiled and rehabilitated (post-spill) and presumably uncontaminated birds. Post-spill pelicans released with color leg bands alone, or bands plus harness-mounted satellite GPS tags, were relocated and visually assessed in the field at non-breeding communal roosts and compared to surrounding unmarked pelicans in the general population. Non-oiled pelicans bearing GPS tags were also included. Post-spill pelicans lagged the general population in molt of ornamental yellow crown feathers, but hind neck transition into white plumage did not significantly differ. Post-spill and non-oiled pelicans wearing GPS tags had lower gular redness scores than unmarked, non-oiled birds. Pre-breeding gular pouch redness of post-spill pelicans was more strongly influenced by wearing of a GPS tag than prior oil contamination and rehabilitation. Gular pouch redness of post-spill pelicans in the first 18 m after release was positively correlated with long-term survivorship. If gular pouch color is a condition-dependent sexual signal, and overall health influences molt progression, our results indicate that many post-spill pelicans marked with bands alone were in relatively good condition entering breeding season, but those released with electronic tags experienced additional stress from the equipment, introducing a confounding variable to the post-release study. [ABSTRACT FROM AUTHOR]

There is ongoing public debate about the best course of action to take when wildlife are affected by oil spills. Critics of wildlife rehabilitation suggest that the cleaning and release of oiled animals is a waste of resources focused on individual animals (not populations); thus, the most responsible course of action is to immediately euthanize affected animals. These critics claim that survival of rehabilitated animals is poor, and that the funds spent on rehabilitation would benefit wildlife more if spent on other conservation efforts. In this opinion piece, with a focus on birds, we review reasons for engaging in a coordinated response to oiled wildlife that includes cleaning and rehabilitation. The reasons for responding to oiled wildlife in any capacity include ethical, human safety, and legal aspects. Our rationale for proposing that responders attempt to rehabilitate wildlife, rather than planning on immediate euthanasia, includes financial, scientific, and additional ethical reasons. Financially, costs for wildlife rehabilitation are typically a very small portion of overall oil-spill response costs, and are typically independent of postspill enforcement and funds used to restore injured natural resources. Scientifically, we review recent studies that have shown that animals cleaned and rehabilitated after oil spills can often survive as well as nonoiled control animals. Ethically, some people would consider individual animals to have intrinsic value and that we, as consumers of petroleum products, have an obligation to reduce suffering and mitigate injuries associated with such accidents. For these reasons, we suggest that, although humane euthanasia should always be considered as an option for animals unlikely to return to normal function after rehabilitation, response to oil spills should include a coordinated effort to attempt wildlife rehabilitation. [ABSTRACT FROM AUTHOR]