Mariana Abarca is an insect ecologist studying plant-insect interactions from a global change perspective. Insects are one of the most diverse groups of living organisms both in terms of species richness and ecological function. Anthropogenic threats, such as habitat loss and degradation, climate change, pollution, pesticide use and altered plant communities have triggered severe insect population declines characterized not just by extinction of some species, but also by lowering abundance of common species. Research in the Abarca lab combines natural history observations, experimental manipulations both in the field and the laboratory, and implementation of ecological modeling techniques to study how herbivorous insects respond to seasonal alterations, thermal stress and changes in the community composition of their host plants and natural enemies.

Current research topics include:

• Assessing the effects of thermal stress and novel host plants on the performance and seasonality of moths and butterflies.
• Evaluating the evolutionary and ecological trade-offs that affect herbivore diet breadth (in collaboration with Dr. Gina Wimp, Georgetown University, Dr. Mayra Vidal, University of Massachusetts Boston, Dr. Shannon Murphy and Dhaval Vyas, University of Denver).
• Monitoring of insect populations and the ecosystem services they provide in pollinator gardens and across urbanization gradients.

Selected Publications

Abarca M., Spahn R. 2021. Direct and indirect effects of altered temperature regimes and phenological mismatches on insect populations. Current Opinion in Insect Science. 47: 67-74.

Abarca M., Lill J. T., Weiss M. R. 2020. Host plant and thermal stress induce supernumerary instars in caterpillars. Environmental Entomology 49:123-131.

Abarca M. 2019. Herbivore seasonality responds to conflicting cues: Untangling the effects of host quality, temperature, and photoperiod. PLOS One, 14 (9), e0222227.

Abarca M., Larsen A. E., Ries L. 2019. Heatwaves and novel host consumption increase overwinter mortality of an imperiled wetland butterfly. Frontiers in Ecology and Evolution 7:193.

Abarca M., Larsen A. E., Lill J., Weiss M., Lind E., Ries L. 2018. Inclusion of host quality data improves predictions of herbivore phenology. Entomologia Experimentalis et Applicata 166: 648-660.

Abarca M., Lill J., Frank-Bolton P. 2018. Latitudinal variation in responses of a forest herbivore and its egg parasitoids to experimental warming. Oecologia 186: 869-881.

Abarca M., Boege, K. 2011. Fitness costs and benefits of shelter building and leaf trenching behavior in a pyralid caterpillar. Ecological Entomology 36: 564-573.