Managing gardens for wildlife: Features that predict mammal presence and abundance in gardens vary seasonally

Abstract

Residential gardens in urban areas offer substantial opportunities for biodiversity conservation. To realize this opportunity, a comprehensive understanding of which species prosper in gardens, which mechanisms promote their use of these green spaces and how these mechanisms can be manipulated by residents to achieve conservation outcomes, is needed. While substantial progress has been made in evaluating the mechanisms that influence the diversity, presence, and abundance of wildlife in gardens, how these mechanisms vary seasonally is largely unknown. This study investigated whether the garden features influencing the presence and/or abundance of arboreal, flying, and ground-dwelling mammals in gardens varied seasonally using acoustic, trapping, and spotlighting surveys undertaken in four consecutive seasons (2018/19) in 52 gardens in southwestern Australia. As animal behavior and resource availability varies seasonally, we predicted that garden features influencing the presence and abundance of mammals in gardens would also vary seasonally. For arboreal and ground-dwelling mammals, we found that some garden features (e.g., canopy cover and presence of dogs, respectively) were important in more than one season; however, none were important in all seasons with most only being influential in one. No garden features predicted the presence of flying mammals in more than one season. Our results suggest that sampling in a single or few seasons may fail to identify features influencing wildlife at times other than in the season of sampling, or alternatively, may overemphasize factors that do not operate across all seasons. Studies that consider the mechanisms on a seasonal basis will provide a more comprehensive list of features influencing the presence and abundance of animals in gardens. We suggest it is both those features that support wildlife in multiple or all seasons, and those that support critical life-history events in a single season that could contribute to conservation if manipulated by residents appropriately.