Derek B. Spitz, Darren A. Clark, Michael J. Wisdom, Mary M. Rowland, Bruce K. Johnson, Ryan A. Long, Taal Levi

Recurrent environmental changes often prompt animals to alter their behavior leading to predictable patterns across a range of temporal scales. The nested nature of circadian and seasonal behavior complicate tests for effects of rarer disturbance events like fire. Fire can dramatically alter plant community structure, with important knock-on effects at higher trophic levels, but the strength and timing of fire's effects on herbivores remain unclear. We combined prescribed fire treatments with fine-scale location data to quantify herbivore responses to fire across three temporal scales. Between 2001 and 2003, 26 stands of fir (Abies spp.) and Douglas-fir (Pseudotsuga menziesii) were thinned and burned; 27 similar stands were left untreated as experimental controls. Analyzing female elk (Cervus canadensis) locations across 21 years (1996-2016), we found crepuscular, seasonal and successional shifts in behavioral responses to fire. Elk displayed "commuting" behavior, avoiding burns during the day, but selecting them at night. Elk selection for burns was strongest in early summer and the relative probability of elk using burns peaked quickly (5 yrs post burn) before gradually returning to pre-treatment levels (15 yrs post burn). Our results demonstrate that fire history has complex, persistent effects on herbivore behavior, and suggest that herbivores benefit from heterogeneous landscapes containing a range of successional stages. This article is protected by copyright. All rights reserved.