How do invasive predators and their native prey respond to prescribed fire?

Area of Science:

• Ecological responses to fire
• Invasive species ecology
• Wildlife management

Background:

• Fire is a significant ecological driver, influencing predator-prey dynamics and resource availability.
• Invasive predators like feral cats (Felis catus) and European red foxes (Vulpes vulpes) are a concern in Australia, with potential for increased activity post-fire.
• Understanding wildlife responses to prescribed burns is crucial for effective land management.

Purpose of the Study:

• To investigate the impact of prescribed fire occurrence, extent, and history on the activity of invasive predators (cats, foxes) and native mammals in southeastern Australia.
• To determine how fire interacts with habitat variables (vegetation, topography, proximity to human settlements) to influence mammal activity.
• To assess the short-term effects of prescribed burns on different native mammal size classes.

Main Methods:

• Camera traps were deployed to monitor mammal activity (detection frequency) before and after a prescribed burn.
• Statistical analyses were used to test the effects of fire and its interaction with environmental variables on mammal activity.
• Mammal species were categorized by size: small (<800 g), medium (800–2000 g), and large (kangaroos).

Main Results:

• Prescribed fire showed little influence on the activity of feral cats and European red foxes.
• No significant effect of prescribed fire was observed on the activity of kangaroos or small native mammals.
• Medium-sized native mammals exhibited negative associations with prescribed fire extent, indicating a short-term detrimental impact.

Conclusions:

• The study found limited evidence that prescribed fire increases the activity of invasive cats and foxes, a potentially positive outcome for conservation.
• Prescribed fire extent appears to negatively affect medium-sized native mammals in the short term.
• Future research should utilize GPS tracking to understand fine-scale predator movements post-fire to better inform management strategies in protected areas.