What drives the abundance of marsupial carnivores in production forest landscapes?

Abstract

Production forest landscapes provide important habitat for wildlife but expose them to disturbances from forestry practices. Understanding how threatened carnivores use production forests can inform management practices to improve their conservation. While there have been many studies of eutherian carnivores in production forests, the use of these landscapes by marsupial carnivores is poorly understood. Using a network of remote cameras, we investigated the use of forestry landscape features by two endangered marsupial carnivores, Tasmanian devils (Sarcophilus harrisii) and eastern quolls (Dasyurus viverrinus). Devil and quoll abundance increased with the extent of timber plantations within production forest landscapes. Overall, devils were positively associated with higher tree density and eastern quolls with indicators of open habitat such as less understorey, fewer trees and more grassland. Within plantations, devil abundance increased with the volume of windrows (piles of woody debris from harvesting arranged in rows), as did eastern quoll abundance in pine plantations. Eastern quoll abundance was higher in pine plantations established on pasture than those established on cleared native forest land, and in eucalypt plantations, higher with windrows comprised of plantation debris. Neither species showed a strong response to logging-related features in native forest such as time since harvest, though eastern quolls were positively associated with log cover. Our results demonstrate that plantations provide valuable habitat for marsupial carnivores and that they can persist in harvested native forests. Windrows likely benefit devils and eastern quolls by providing denning, shelter and foraging opportunities, and should be managed as important habitat features for carnivores. These findings can be used by forest managers to guide decisions and help maintain threatened carnivore populations in human-modified landscapes.