Ecosystem linkages and global change

As an NSF Postdoctoral Research Fellow, I studied how resource subsidies influenced ecosystem structure and function in a subarctic biome in northeastern Iceland. At Lake Mývatn, Iceland, large numbers of midges emerge in the summer and fly over adjacent terrestrial ecosystems where they create dense mating swarms. Mated females return to the lake to lay eggs, but the males stay behind and perish in the terrestrial landscape. I investigated how these insect subsidies changed the composition of plant and insect communities, as well as nutrient cycling. Findings from this research show that the addition of insect carcasses to heathland soils can significantly increase litter decomposition rates and shift plant composition towards grass species. Future studies will evaluate how those insect subsidies will change food web dynamics under different environmental contexts. 

Publications

McCary, M.A., M.D. Kasprzak, J.C. Botsch, D. Hoekman, R.D. Jackson, and C. Gratton. 2021. Aquatic insect subsidies influence microbial composition and processing of detritus in near-shore subarctic heathland. Oikos 130: 1523-1534.

McCary, M.A., R.D. Jackson, and C. Gratton. 2021. Vegetation structure modulates ecosystem and community responses to spatial subsidies. Ecosphere 12: e03483.

McCary, M.A.*, J.S. Phillips*, T. Ramiadantsoa, L.A. Nell, A.R. McCormick, and J.C. Botsch.  2021. Transient top-down and bottom-up effects of resources pulsed to multiple trophic levels. Ecology 102: e0197. * equal contribution

Hoekman, D., M.A. McCary, J. Dryer, and C. Gratton. 2019. Reducing allochthonous resources in a subarctic grassland alters arthropod food webs via predator diet and density. Ecosphere 10: e02593