Welfare biology work on how fires harm wild animals and what to do about it

Welfare biology work on how fires harm wild animals and what to do about it

27 Aug 2020

During the last several years Animal Ethics has been working to promote academic work about the situation of wild animals, focusing on work that has great potential for making a practical difference to their wellbeing. Last year we provided funding for Jara Gutiérrez, a biologist with a PhD in animal welfare science, to do postdoc research at the Autonomous University of Madrid on the effects of fires on animals in the wild.

Fires harm animals living in the wild in many ways, and it is important to recognize how they are affected and recognize opportunities for reducing these harms. There is a very concerning lack of research on the individual welfare of animals living in the wild, so publications like this are especially important now so that we can begin to reverse this situation.

This research can be useful to inform policies and design protocols aiming at helping animals during and after fires. We are also excited about this research because it can encourage similar future research by other scientists. We have published before about this issue here:

Animals helped in natural disasters and fires

Animals in natural disasters

Fire season in Australia: wild animal suffering and response

We are happy to announce that her work has now been completed. We are publishing a report here including a literature review of more than 400 publications by Gutiérrez about how animals are harmed by forest fires and about how they can be helped. In addition, she has submitted a paper for publication in a biology journal, which is also available as a preprint here:

Fires in nature: a review of the challenges for wild animals

We want to thank our very generous donors for enabling us to fund important projects such as this. This was possible thanks to an EA Animal Welfare Fund grant. Your support has also been vital in enabling this research and contributing to a more positive future for all animals. If you would like to see more work of this kind, please consider supporting our work.

The study can be downloaded here. Below you can see a more detailed explanation of the research project by Jara Gutiérrez at the Autonomous University of Madrid:


Challenges posed by fires to wild animals and how to help: a literature review

Executive Summary


The lives of wild animals are not idyllic. In fact, there are major causes of animal suffering in nature, such as wildfires. Both natural and human caused fires can cause great harm to animals living in the wild. Fires show a growing tendency to burn larger areas (Doerr & Santín 2016), suggesting a trend of less frequent but larger forest fires (Westerling 2016), which is expected to continue in the coming years.

When evaluating the consequences of fires, attention falls almost only to those fires that have high costs and/or sometimes tragic impacts on humans (Yell 2010). Moreover, studies assessing the negative impact of fire on animals often focus not on wild animals but on domestic species and farmed animals, mainly out of economic interests.

Current research has collected scientific evidence of sentience in numerous animals, including wild animals. Because many animals are capable of perceiving challenging situations, fires can be a threat to the welfare of animals living in the wild.

In general terms, a fire is a stressful event for animals that triggers physiological, endocrine, and behavioral responses as a result of an evolutionary adaptation to survival. Apart from the physiological damage, fire can involve discomfort, fear, and distress in animals.

The study of how wildfires affect animals – directly and indirectly, in the short and long term – can be complex. There can be substantial variations depending on the species in the involved areas and the environments they are in, as well as the characteristics of the fires. To date, more research on welfare biology and on the monitoring and evacuation of wild animals at risk during fires is crucial to improving our understanding of the ways animals are harmed and how we can help them, as well as to encouraging interventions and further research on the subject.

Objectives and Methodology

This review aims to summarize the main negative effects of fires on wild animals, and to suggest some improvements in the design of future interventions. The methodology consisted of the evaluation of the most relevant scientific articles and reviews related to the topic, with the aim of making a sufficiently broad revision based on the existing literature considering the overall physiological, psychological, and ethological challenges that wildfires cause in animals.

The project is important for several reasons: (1) it can provide a better understanding of how the lives of animals in the wild are affected by one of the threats that they face, using knowledge gathered in ecology studies; (2) it can form the basis for designing future protocols for rescuing animals or preventing harms; (3) it can help to raise concern for the situation of wild animals as individuals; and (4) it can help to develop work on welfare biology by identifying promising future lines of research related to the topic.


How animals respond to fire depends on many factors including their life history, evolutionary adaptations to fire, and individual stress coping styles, in addition to the characteristics of the fire.

The first response to fire is the decision on whether to flee or remain in the area that is being burned. This behavior depends on the species, environmental circumstances, and mobility. While some individuals attempt to flee the flames, swimming or running anxiously, others attempt to take refuge in burrows which they are reluctant to leave. Some small mammals have been seen fleeing the flames while carrying young with eyes still closed on their backs. In contrast, other individuals, usually larger mammals, remain quietly foraging just a few meters from the flames.

As they flee, animals can face increased exposure to predators, risk of mortality due to physical weakness, and collisions with vehicles. Understanding the movement and flight patterns of animals in response to fire may help in establishing key areas for rescue and supplementation actions. For example, fire edges can be primary intervention areas.

Whether they flee or stay in the area near the fire or in shelters, extreme environmental temperatures from fire predispose animals to acute heat stress, which causes numerous physiological alterations, such as hyperventilation (Radford et al. 2006), dehydration (which potentially damages organs), lipid metabolism disturbance, plasma cholesterol and phospholipids reduction, increases in the amount of fat excreted in the feces (O’Kelly 1987) and tissue stress (Islam et al. 2013). Heat stress effects worsen when accompanied by burns on limbs, feet, and paws produced by hot surfaces during the fire.

In addition to physiological disturbances, behavioral alterations have been reported to occur in response to heat stress, including loss of coordination, which in turn increases the risk of disorientation and falling (Radford et al. 2006), making it difficult to escape, and also an increase in the display of stress-related behaviors (Debut et al. 2005). Overall, acute heat stress generates distress and pain in the individual, and can even be fatal.

Some proposed measures to prevent acute heat stress are providing drinking fountains and carefully handling rescued animals (keeping them in the dark, without potential stressful exposure, in a well-ventilated box, offering them water, etc.).

Apart from acute heat stress, wounds, injuries, and other physiological damage are frequent for animals that are victims of natural disasters such as fires, which can lead to high mortality rates. Although there are currently no accurate estimates of the number of animals that die each year in fires, post-fire mortality to date is quantified by direct estimates, either through software (Jeffers et al. 1982; Silveira et al. 1999b), or by relying on recent reports estimating previous animal populations sizes.

In addition, intensified post-fire predatory activity has been reported (Parkins et al. 2019a), which increases the risk of prey mortality (Rickbeil et al. 2017). Injuries such as muscle weakness or respiratory failure may increase the risk of being predated, because a predator will be more likely to hunt a weakened and disoriented animal.

During fires, affected animals require specific intervention, which has numerous challenges as well. Providing food to starving individuals and medical assistance to injured or sick animals is necessary. For instance, provisional in-situ camps provided with electric generators and sufficient medical supplies could be set up to treat and give first aid to those animals. Food and water areas can also be easily arranged along the natural transects.

For those individuals that require a period of rehabilitation in captivity before reintroduction, some recommendations should be considered:

First, the veterinary evaluation should include a first diagnosis of the individual’s wounds, injuries, and previous illnesses. Factors such as the depth, extent, and locations of burns and wounds will determine the animal’s rehabilitation and survival success.

Second, specific nutritional supplementation can be provided to wild animals, as their metabolic requirement varies when they are sick or hurt.

Third, environmental enrichment through structures, visual/auditory/tactile stimulation, taste, cognitive stimulation, social housing, and exercise should be provided to wild animals during captivity, as they are essential for their recovery.

The successfully recovered individuals can be released into the wild. Released individuals can be monitored in order to assess the effectiveness of post-fire rehabilitation processes, which can be adjusted to improve future intervention efforts (Muths et al. 2014) and to closely examine fire effects (Engstrom 2010).

Future perspectives and recommendations

The gradual inclusion of non-domesticated animals in evacuation plans during fires is feasible, and crucial for the benefit of wild animal communities. Interventions must be improved, especially since the increase in human activities will potentially affect the natural environment and the quality of life of wild animals.

All potential suffering, distress, and discomfort during captures, rescue interventions, human proximity, and handling should be avoided. Efforts should be made to reduce the invasiveness of the evacuation and care procedures.

More efficient application of evacuation plans can reduce people’s confusion when it comes to assisting affected animals. Providing the public with consistent information raises awareness and allows for more efficient collaboration between the public and volunteers. For instance, multidisciplinary approaches through technological advances and media participation is essential to exchanging information and organizing interventions in a quick and efficient way.

Similarly, more research is needed on topics such as long-term welfare (post-fire), evacuation plans and training, how animals detect and respond to fire (psychologically and physiologically), understanding fire processes, and others.

Limitations of this study

To date, scientific studies on the challenges that fires present for animal welfare have not been deeply developed. Information on the effects of fire on wild animals tend to report plant community modification by fire and the consequent influence on food, cover, and habitat used by various animal species (Lyon 1978), without assessing in depth the harmful effects that fires exert on individuals.

The current review has faced a lack of quantitative studies systematically assessing the harmful effects that fires have on wild animals, including for example monitoring the affected animals. In addition, although variation in the nature of fires is one of the main problems when attempting any generalization about the effects of fire on wild animals (Lyon 1978), there is no extensive categorization of the effects depending on these characteristics of the fire.


Nowadays fires occur with greater intensity and frequency. As a result, wild animals may not be adapted to flee from the fire and survive. Individuals’ responses depend on numerous circumstances, including fire characteristics, life history traits, the type of management of the daily energy budget of the species, and individual stress coping strategies. Fires may increase the risk of injury, disease, stress, and mortality for animals living in the wild, resulting in physiological and psychological harm, experiences of suffering, discomfort and pain, and long-term detrimental consequences.

Wild animals can benefit from effective rescue, rehabilitation, and release during fires, and post-release monitoring must accurately evaluate their outcome success. The resulting information can be used to educate veterinarians, volunteers, rehabilitators, and the public in the prevention of the suffering and deaths of as many animals as possible in future fire events, which ultimately benefits animal welfare.