Department of Biological Sciences

Rachel Lasley-Rasher Ph.D.

Assistant Professor of Biology
Rachel Lasley-Rasher

Office Location

476B Science ("C" Wing)



Academic Degrees

  • Ph.D., Biology, Georgia Institute of Technology, 2012
  • B.S., Marine Biology, University of the Virgin Islands, 2005


Dr. Lasley-Rasher joined the Biology Department at USM in 2017. Previously, she was a postdoctoral fellow at the University of Maine, and she served as the Research Coordinator for the Maine Sea Grant program. She is a marine ecologist who studies effects of prey behavior on predator-prey interactions and large-scale dynamics at the population, community, and ecosystem levels.

Dr. Lasley-Rasher teaches courses in ecology (BIO 203, BIO 337) and organismal biology, and she contributes to the evolution, biodiversity, and ecology course (BIO 107) within the introductory biology sequence.

Research Interests

I am a zooplankton ecologist. I study the big impacts of small organisms that occupy basal trophic levels. These animals play a critical role in transferring energy to higher consumers including many commercially important fish. I am most interested in interdisciplary research questions that relate individual-scale behaviors such as predator avoidance, mate finding, and migration to community and ecosystem-scale effects. I have always been intrigued as to how small animals navigate the vast, viscous, and dilute world that is the marine environment.

My previous work includes determining the indirect effects of predators on copepod reproductive success and measuring the behavioral effects of ingesting toxic algae on copepod swimming behavior and predator encounter. More recently, I have used historic fish diet data from the National Oceanic and Atmospheric Administration (NOAA) to quantify the abundance patterns of small shrimp across the Northeastern U.S. shelf ecosystem.

Currently, I am working on a project to determine how the estuarine food web has changed following a historic restoration effort in the Penobscot River. The Penobscot River restoration is one of the largest habitat restoration projects in our nation’s history, opening thousands of kilometers of riverine habitat for migratory fish, such as river herring. I am working with collaborators from NOAA and the University of Maine to see how the dramatic increase in river herring is affecting zooplankton distribution and abundance.

Recent Publications

Lasley-Rasher, R., Nagel, K., Aangra, A. and Yen J. (2016) Intoxicated copepods: ingesting toxic phytoplankton leads to risky behaviour. Proceedings of the Royal Society B. 283(1829): 20160176.

Lasley-Rasher, R., Brady, D., Smith, B. and Jumars, P. (2015) It takes guts to locate mobile crustacean prey. Marine Ecology Progress Series. 538: 1-12

Lasley-Rasher, R., Burdett-Coutts, V., Kramer, A. and Yen, J. (2014) Assessing the in situ fertilization status of two marine copepod species, Temora longicornis and Eurytemora herdmani; How common are unfertilized eggs in nature? PLoS ONE 9(11): e112920. doi:10.1371/journal.pone.0112920.

Heuschele, J., Ceballos, S., Andersen Borg, C., Bjærke, O., Isari, S., Lasley-Rasher, R., Lindehoff, E., Souissi, A., Souissi, S., and Titelman, J. (2014) Non-consumptive effects of predator presence on copepod reproduction: insights from a mesocosm experiment. Marine Biology 161(7): 1653-1666.