Waste reduction decreases rat activity from peri-urban environment

Area of Science:

• Ecology
• Invasive Species Biology
• Urban Wildlife Management

Background:

• Invasive species, particularly Rattus species (Rattus rattus and Rattus norvegicus), pose significant ecological challenges globally due to their competitive exclusion and broad diets.
• Understanding the foraging behaviors of urban-adjacent rodent populations is crucial for effective management strategies.
• Human food supplementation is a suspected driver of invasive rat populations in peri-urban environments.

Purpose of the Study:

• To investigate the dependency of invasive Rattus species on human food resources in peri-urban areas.
• To quantify changes in invasive rat and native small mammal activity in response to reduced human food supplementation during the COVID-19 lockdown.
• To evaluate waste management as a potential non-invasive population control method for invasive rodents.

Main Methods:

• Utilized linear regression modeling to analyze rodent activity data.
• Employed camera traps to monitor invasive rat activity before and during the COVID-19 lockdown.
• Compared activity levels of invasive Rattus species and native small mammals near human food waste sources.

Main Results:

• A statistically significant decrease (p < 0.001) in invasive Rattus activity was observed following the reduction of human refuse during the lockdown.
• Native small mammal activity levels remained unchanged (p = 0.1) despite the decrease in human food supplementation.
• The study documented invasive rat activity patterns in relation to human waste availability.

Conclusions:

• Invasive Rattus populations exhibit a strong dependency on human food supplementation in peri-urban ecosystems.
• Effective waste management practices can serve as a viable, less-invasive method for controlling invasive rat populations.
• Findings support the use of ecological management strategies over conventional rodenticides for conservation purposes.