- Authors:
- Quinn M.R. Webber
- Kristy M. Ferraro
- Jack G. Hendrix
- Eric Vander Wal
This repository contains the code accompanying the paper “What do caribou eat? A review of the literature on caribou diet”.
Scripts are under scripts/. Input data are provided under input/ and with these data all analyses and figures can be replicated. Downstream output data are available under output/.
Caribou and reindeer (Rangifer tarandus) diet has been historically studied for specific herds, yet few comprehensive circumpolar analyses of Rangifer diet exist. As such, the relative importance of various plant groups, including lichen, is debated. We provide a systematic overview of 31 caribou studies reporting caribou diet and test biologically relevant hypotheses about spatial and temporal dietary variation. Our results indicate that in the winter caribou primarily consume lichen, but in warmer seasons, and when fewer sympatric competitors are present, caribou primarily consume graminoids and other vascular plants. These general patterns were also ecotype-specific; we found that woodland, mountain, and barren-ground caribou had higher proportions of lichen in their diet, while Peary caribou and reindeer had lower proportions of lichen and higher proportions of graminoids in their diet. Our description of caribou diet reveals that while in some circumstances caribou occupy a specialized dietary niche, but in other circumstances or ecosystems they appear to occupy a generalized dietary niche. As Boreal and Arctic ecosystems are affected by climate change, the type and volume of food consumed by caribou has become an increasingly important focus for conservation and management of caribou.