Saving Wild Animals, Before And After Rehabilitation
Wild animals are often victims of human activities like vehicle collisions, domestic animal attacks, and environmental disasters such as oil spills and wildfires. Wild animal rehabilitators around the world rescue, care for, and release millions of animals every year. This work is extremely important, not only for the animals saved but for the populations and ecosystems to which they contribute. Despite best efforts, many animals do not survive rehabilitation or die soon after release.
Many rehabilitation centers use protocols based on trial and error, shared knowledge, and authority guidelines. However, scientific evidence is essential to inform rehabilitation practices so that we can identify effective ways to maximize the chances of survival at all stages. This should be an ongoing process of evaluation and method refinement.
Along these lines, a recent scientific review was conducted to identify factors associated with survival during rehabilitation and after release. The authors reviewed 112 articles about mammals and birds from Australia, Europe, North America, and Africa. They gathered data on the reasons for rescue, the percentage of animals that survived rehabilitation, the short-term (<6 months) and long-term (>6 months) survival after release, and the causes of death.
By comparing these measures to the characteristics of the animals, study location, and environment of release, the authors determined the most important factors affecting survival and discussed strategies to address them.
Most animals were rescued following injury or harm from human activity, reported in 48% of studies. This was followed by non-specific or unknown causes (42.2%) and environmental causes (9.8%). Of the reasons for entering rehabilitation related to human activity, the top five most common are as follows:
Most deaths during rehabilitation were related to the reason for admission. The average unassisted death rate (not due to euthanasia) for both birds and mammals was around 18% and varied by location. While unassisted deaths among mammals were largely linked to their position in the food web, the probability of unassisted deaths among birds varied by location: It was highest in North America (27%) followed by Europe (20%), Africa (15%) and Oceania (10%). These deaths may indicate poor triage, treatment, or husbandry. Alternatively, they could reflect a difference in decision-making around euthanasia, where the decision to euthanize might be delayed in North America compared to other locations.
When wild animals are released from rehabilitation, many continue to face life-threatening risks. Most deaths after release were due to attacks by other animals (24%) including domesticated animals, wild predators, and competitors. This was followed by vehicle collisions (13%) and hunting (12%). As a category, human activity was responsible for 41% of deaths, followed by non-specific or unknown causes (30%) and environmental causes (29%).
The study location had a significant effect on bird survival. Studies in Africa reported the highest likelihood of survival (65%) in the first six months after release, followed by North America (55%), Oceania (50%), and Europe (49%). The survival likelihood after the first six months was also highest in Africa (72%), followed by Oceania (65%), Europe (31%), and North America (6%).
There are several steps that wild animal advocates can take to mitigate threats during and after rehabilitation. The first is focusing on treatment and training. Adequate equipment, facilities, trained personnel, and response protocols can improve survival rates. Birds admitted by animal collection officers or veterinarians had a better chance of survival than those brought in by the public. It’s important to push for veterinary checks and assessments before animals are released back into the wild. Proper training and education will also improve response times and ensure that appropriate treatments are being given.
Animals kept in captivity for too long have poorer chances of survival as they become too comfortable around humans, in turn showing a loss of wild behaviors and a reduced fear of predators. Minimizing human contact and time kept in rehabilitation facilities can help prevent these effects. Training animals to hunt, forage, and practice wild behaviors is critical. This includes providing flight tunnels for birds and training predators to hunt before release.
When releasing animals back into the wild, choosing a safe and appropriate environment is vital. Given that predator attacks are the main cause of death after release, rehabilitators should work with local environmental agencies to learn about predator numbers and identify safe release environments. It is also important to consider selecting habitats familiar to the animal that meet their survival needs. Animal advocates should review policies that encourage rehabilitators to release animals near where they were originally rescued, especially if the location is rife with human activity or environmental destruction. In general, habitat selection should be highly dependent on the species in question.
In a world where escalating climate change, urban expansion, and human activity are causing devastation to wild animals, we must form robust, science-based protocols that improve rehabilitation methods and minimize animal suffering. As animal advocates, it’s also important to raise awareness of how we can reduce threats causing harm in the first place. Humans are responsible for most harm caused to wild animals. We must also be responsible for helping them survive.