Consumption of red maple in anticipation of beech mast-seeding drives reproduction in Eastern chipmunks

1. Understanding the determinants of reproduction is a central question in evolutionary ecology. In pulsed resources environments, the reproduction and population dynamics of seed consumers is driven by pulsed production of seeds by trees, or mast-seeding. In Southern Québec, eastern chipmunks (Tamias striatus) exclusively reproduce during the summer before and the spring after a mast-seeding event of American beech. They thus seem to anticipate beech mast by reproducing during early summer, so that juveniles can emerge at the time of maximum beechnut abundance during late summer.
2. However, the cues allowing chipmunks to anticipate beech mast remain unknown, and the existence of the anticipation process itself has been questioned. To tackle those issues, we investigated the links between the nutritional ecology and reproduction of adult chipmunks and compared their spring diet in mast- vs post-mast years.
3. We monitored female’s reproductive status (N=446), analyzed cheek pouch conte...