A long-term experiment reveals strategies for the ecological restoration of reptiles in scattered tree landscapes

Abstract

Long-term faunal responses to restoration eforts can be very diferent from those in the short term, but are often not quantifed systematically to identify ways that maximise restoration outcomes. We report on a 9-year landscape-scale ecological experiment that tests the long-term responses of reptile populations to coarse woody debris (CWD) addition, reduced native macropod grazing, and prescribed fre. We found that reptile species richness was increased 9 years after CWD addition, as was the abundance of several common reptile species. Further, the more CWD was added to the system, the more benefts were aforded to reptiles. The positive efect of CWD depended on the surrounding vegetation structure and was greater in sites with low tree and shrub cover. Further, lower levels of macropod grazing appeared to lessen the efects of CWD addition in the long term. Our results show that restoration projects in open woodlands and scattered tree ecosystems should consider the addition of CWD as a fundamental element of their management actions. To maximise benefts of CWD addition for reptiles, we recommend a strategy of placing CWD in areas with low tree and shrub cover rather than areas with high tree and shrub cover. The addition of CWD in such areas would provide crucial shelter and foraging substrates for reptiles in a comparatively hostile portion of the landscape. Our study helps to establish guidelines for achieving long-lasting efects of ecosystem restoration for vertebrates and demonstrates the benefts of monitoring vertebrates over the long term.