Behaviour 2019
Heritability and Cross-Context Repeatability of Food Caching in a Wild Mammal  
Andrea E. Wishart1, Stan Boutin2, Andrew G. McAdam3, Ben Dantzer4, David W. Coltman2, Jeffrey E. Lane1. 1University of Saskatchewan, Saskatoon, Saskatchewan, Canada; 2University of Alberta, Edmonton, Alberta, Canada; 3University of Colorado, Boulder, Colorado, United States; 4University of Michigan, Ann Arbor, Michigan, United States

Although selection should favour high resource accumulation, there is still nearly ubiquitous variation in individual resource acquisition. In fluctuating environments, behaviours associated with resource acquisition (e.g., food-caching) may be influenced by underlying genetic components, personality, and/or within-individual trade-offs. We aimed to determine whether observed variation in food-caching success maintained by repeatable caching phenotypes or plasticity. North American red squirrels (Tamiasciurus hudsonicus) in the southwest Yukon, Canada defend solitary territories year-round centered around a larder in which they cache cones of white spruce (Picea glauca). We quantified annual caching success as new cones in the larder, linked to territory owners through behavioural observations and live-trapping. Leveraging a genetically determined pedigree, we found low heritability and repeatability of annual caching success across years. We investigated adaptive plasticity by examining whether different caching strategies relative to resource abundance influenced survival to the next year. This work gives insight to evolution of resource acquisition in fluctuating environments.