Foraging for elements: mammalian responses to plant stoichiometry across scales

• Main Author: Balluffi-Fry, Juliana
• Format: Thesis
• Language: English
• Published: Memorial University of Newfoundland 2019
• Subjects: Alces alces
• Online Access: https://research.library.mun.ca/14528/; https://research.library.mun.ca/14528/1/thesis.pdf

Energetic demands, nutritional needs, and the scale of foraging collectively influence terrestrial herbivore feeding decisions to meet nitrogen (N) intake requirements. I measured moose (Alces alces) selection for distributions of browse N content and biomass at three scales. Additionally, I measured snowshoe hare (Lepus americanus) preference for browse N content under varying energetic and nutritional demands using cafeteria experiments. I predicted that both herbivores would select for N content; this selection would be stronger for moose at smaller scales and for hares under greater nutritional demands and weaker for moose at larger scales and for hares under greater energetic demands. Moose responses did not support my scalar predictions, but I uncovered individual-level selection trade-offs. The hare experiments supported my energetic and nutritional demand predictions. Collectively, nutrient availability within terrestrial systems may influence herbivore movement and behaviours, although individuals remain flexible in how they respond to and attain limiting nutrients.