Short-term effects of summer warming on caribou forage quality are mitigated by long-term warming

Rapid Arctic climate change is leading to woody plant-dominated ecosystems with potential consequences for caribou foraging and nutritional ecology. While warming has been clearly linked to shrub expansion, the influence of higher temperatures on variables linked to the leaf-level quality of caribou forage is equivocal. Moreover, warming results in a complex set of ecosystem changes that operate on different timescales such as not only rapidly accelerating phenology, but also slowly increasing thaw depth and plant access to soil resources. Here, we compare changes in leaf nitrogen (N) concentration, digestibility, and protein-precipitating capacity (PPC) in short-term (i.e.