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bioRxiv · 10.1101/2023.03.05.531208

Movements and habitat selection of a marsupial carnivore in a modified landscape

Abstract

Landscape modification is a major threat to carnivores worldwide, but modified landscapes can also provide important habitat for these species, as protected areas alone are insufficient. Understanding how carnivores use modified landscapes, such as production forests, can inform management strategies to improve the value of these landscapes to carnivores. Little is known about habitat selection by marsupial carnivores in production forests, where they occupy a similar ecological niche to their more well-studied eutherian counterparts. We used GPS tracking, Hidden Markov Models, and Manlys selection ratios to identify the habitat selected in 3 behavioral states by the largest marsupial carnivore, the Tasmanian devil (Sarcophilus harrisii), in a timber plantation-dominated landscape. Behavioral states were approximated as: state 1, resting or feeding at a carcass; state 2, foraging; and state 3, travel. Devils did not show preferences for any of native forest, native grassland, and plantation in any behavioral state. Within plantations, devils preferred a plantation age of 4-7 years (selection ratio [wi] = 1.52). Devils preferred roads (state 1: wi = 2.71, state 2: wi = 2.48, state 3: wi = 2.97) and plantation edges (state 1: wi = 2.38, state 2: wi = 2.24, state 3: wi = 2.78) in all behavioral states, and moved faster on roads and edges than away from them. Together, our results indicate devils use road and edges for foraging (scavenging and hunting) and travel. No measured habitat variables influenced devil home range size. To support devils in plantation landscapes, we recommend maintaining a heterogeneous landscape of different plantation ages and native remnants and reducing the risk of vehicle collisions by minimizing forestry traffic at night. Tasmanian devils share similar adaptable traits to generalist eutherian carnivore species in their use of modified landscapes. Plantations can provide valuable habitat for this and other threatened predator species.

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BibTeXRIS

Jones, E. M., Koch, A. J., Pay, J. M., Mann, D. F., Jones, M. E., Hamede, R. K.. 2023-03-05. Movements and habitat selection of a marsupial carnivore in a modified landscape. https://doi.org/10.1101/2023.03.05.531208

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