This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). This interdisciplinary study combines efforts from mathematicians and ecologists to develop more suitable models and modeling approaches that address issues of interest to both ecologists and resource managers. The specific objectives of this project are threefold. The first objective is to extend mathematical development of a modeling approach for assessing the impact of toxin-mediated interactions between multiple plant species and herbivores. The second objective is to integrate toxin-mediated browsing dynamics into the existent theory of boreal forest community dynamics. The final objective is to explore the roles that landscape disturbance, patterns of patchiness, and adaptive browsing play in shaping the plant community. These models are developed to reflect the biological complexity of plant-herbivore systems and will provide unique insight into how herbivore factors, plant factors, and environmental factors impact the establishment and spread of toxic plants in natural systems. The modeling studies in this project have critical societal importance because of the key role that moose and other herbivores play in indigenous societies in the boreal forest. Moose, the largest herbivore in Alaska, are a major source of protein for residents in interior Alaska. For generations, Athabascan Indians have harvested moose, which provide a valuable nutritional and cultural resource, so changes in moose abundance and distribution can have large impacts on subsistence users. This is especially true in rural areas where availability of alternative resources can be limited, and lack of job opportunities and high poverty levels make subsistence harvest an essential component of rural economies. Toxins in plants are known to affect intake and plant selection in herbivores which in turn can influence ecosystem processes such as succession. Succession in turn influences the quality of moose habitat, distribution, and ultimately harvest. This research project will improve understanding of how toxins influence plant selectivity by moose during succession in the boreal forest. Models developed will explore future scenarios of vegetation, herbivores, and their consequences for subsistence. Additionally, process-based understanding of the impacts of recent climate warming and increases in wildfire on moose abundance and distribution will be improved, and therefore subsistence opportunities for indigenous residents of Alaska. Lastly, such information can help better inform wildlife managers and allow for more proactive management policies.
2009-2013