A new study published in the journal Ecology Letters suggests that wildfires positively affect biodiversity in animal species. While research has shown that ecosystems where fire is a natural occurrence tend to have greater species richness due to various factors, including fire-related adaptations, but less research has been conducted on animal biodiversity and fire. The study’s lead author, wildfire specialist Max Moritz from UC Cooperative Extension, investigated the connection between fire and animal biodiversity by examining global datasets on various factors such as plant biomass, fire observations, and species richness patterns. The researchers found that fire is associated with increased diversity for birds and mammals, and in mammals, fire’s influence was even stronger than that of productivity.

While it might be natural to assume that plant biomass regularly consumed by fire would, in turn, lead to lower animal biodiversity, the study suggests that, in the longer term, there may be evolutionary effects that unleash adaptations and the formation of new species. Fire selects for species that can adapt to and quickly recover from a burn, and fire often creates environmentally complex habitats that meet different species’ requirements. For example, animals with strategies to survive fires or reproduce faster might do better in a fire-prone environment, as could those that use different habitats that emerge in the wake of a blaze.

Despite the connection between fire and species richness, the authors carefully point out that it does not mean fire is good for all ecosystems. In places where fire is not a natural occurrence, its presence “is more of a modern threat than an important process to maintain,” they said. Nevertheless, these findings indicate that fire plays an underappreciated role in generating animal species richness and biodiversity conservation. Furthermore, the study adds nuance to the Latitudinal Biodiversity Gradient, a global pattern of terrestrial biodiversity in which the world’s most biodiverse areas are nearest the equator, with levels of biodiversity generally decreasing toward the poles.

The study’s correlative nature means more granular examinations are required. However, the researchers believe that fire’s resource availability might create favorable environments for some organisms to flourish alongside or over others. “We know that fire creates much heterogeneity and opens up all these niches,” Moritz said, and this could create environments that meet different species’ requirements. The study’s findings suggest that while many see wildfires as purely destructive forces, disasters that blaze through a landscape, charring everything in their paths, they are also generative forces, spurring biodiversity in their wakes.

References

• Fernandez, S. (2023, April 13). Naturally fire-prone ecosystems tend to have more species of birds and mammals, a new study reveals. The Current; UC Santa Barbara. https://www.news.ucsb.edu/2023/020895/wildfires-and-animal-biodiversity
• Moritz, M. A., Batllori, E., & Bolker, B. M. (2023). The role of fire in terrestrial vertebrate richness patterns. Ecology Letters, 26(4), 563–574. https://doi.org/10.1111/ele.14177