Forest type modulates mammalian responses to megafires.

Area of Science:

• Ecology
• Wildlife Biology
• Conservation Science

Background:

• Wildfires are natural evolutionary forces shaping ecosystems.
• Human activities are increasing the frequency and intensity of megafires.
• Understanding megafire impacts on biodiversity is crucial for conservation.

Purpose of the Study:

• To investigate how forest type influences terrestrial mammal responses to a megafire.
• To assess changes in mammalian richness, abundance, and assemblage composition post-megafire.
• To differentiate mammal responses based on burned area proportion within monospecific and polyspecific forests.

Main Methods:

• Comparative analysis of mammal communities before and after a megafire in the Brazilian Pantanal.
• Assessment of species richness, relative abundance, and assemblage composition.
• Partitioning of effects based on forest type (monospecific vs. polyspecific) and burned area proportion.

Main Results:

• Mammalian richness was higher one year after the megafire, likely due to habitat modification attracting herbivores and open-area species.
• Assemblage composition differed between burned and unburned sites, but overall richness and abundance showed no significant change.
• Monospecific forests experienced pronounced declines in mammal species richness and relative abundance compared to polyspecific forests.
• 86% of species showed negative effects on relative abundance, with a strong negative impact on the overall assemblage.

Conclusions:

• Forest type significantly modulates terrestrial mammal responses to megafires.
• Recurrent megafires may lead to regional shifts in beta diversity, favoring open-area tolerant species.
• Conservation strategies must consider forest structure when mitigating megafire impacts on mammal communities.