By Catherine Machalaba of IUCN Member EcoHealth Alliance and Programme Officer with the Wildlife Health Specialist Group of IUCN’s Species Survival Commission.

Wildlife health is an important and growing, yet often overlooked, component of the conservation of wild species.

Just like humans and domestic animals, wildlife are susceptible to intra- and inter-species diseases that can cause morbidity (the number of individuals in poor health in a given time period) and mortality. In natural robust or resilient populations, this is just part and parcel of life, and in some species important in natural population control or for contributing to population genetic health.

Regrettably this situation is becoming increasingly rare with human-induced global change including loss of populations and even species. Many of the drivers of biodiversity loss, such as habitat loss and degradation and overexploitation of species, may put wildlife at increased risk of disease spread through various stressors and from new contact with other populations, other species or environmental pollutants.

Several recent wildlife health concerns have been widely documented and have required extensive efforts for disease prevention and control. Over 100 wild species are known to be susceptible to rabies virus, and it has caused significant die-offs of endangered African Wild Dogs (Lycaon pictus) and Ethiopian Wolf (Canis simensis).

Infections with the chytrid fungus Batrachochytrium dendrobatidis (Bd) and ranaviruses have resulted in large-scale Amphibian declines, with some species extinctions seen from Bd; global wildlife trade has been shown to be a main factor in the global spread of the fungus.

Influenzas have been implicated in die-offs of species ranging from Waterfowl to Harbor Seals (Phoca vitulina). Toxicity from environmental contaminants can cause acute or long-term illness in wildlife, as seen with the pesticide DDT’s role in critical Bald Eagle (Haliaeetus leucocephalus) declines and the veterinary drug diclofenac in Vulture (Gyps spp.) declines.

While wildlife health is a growing concern for the conservation community, there is still limited scientific knowledge around the overall health risks for wild species, and species die-offs often go undiagnosed. Baseline and ongoing monitoring of the health of wild species can provide important and beneficial information to promote the conservation of species. Early detection of disease threats allows for rapid interventions, such as vaccination campaigns, to prevent spread in a population, and detection in one species can serve as sentinels for potential spread to other species.

Samples routinely collected for conservation efforts can often be tested for common diseases or banked for future testing, and health assessments can be integrated into existing capture programs (e.g. for tracking device placement). Once we know more about wildlife health and disease risks, we can work with wildlife managers, land use planners, and a wide array of other stakeholders to prevent or minimize risks to wildlife.

Strengthening infrastructure for wildlife health will allow us to more proactively prevent disease-related species declines. The members of the IUCN Wildlife Health Specialist Group are actively working to promote the health of wild populations, and we encourage the entire conservation community to join us in this effort.

Contact us at: WHSG@EcoHealthAlliance.org, follow us on Twitter @IUCNWildHealth or Facebook IUCN SSC Wildlife Health Specialist Group