Graham Sustainability Institute

Identifying the controls of algal pathogen epidemics and their influence on harmful algal blooms in Lake Erie

Tom Archer, Source: Michigan Sea Grant


Timothy James, Department of Ecology and Evolutionary Biology
Gary Fahnenstiel, U-M Water Center
John Marino, Department of Ecology and Evolutionary Biology

Project Summary

Harmful algal blooms (HABs), caused by rapid growth of certain algal species, are a major economic and ecological problem in freshwater and marine ecosystems. In Lake Erie, these blooms have increased in recent years, driven primarily by climatic conditions and nutrient inputs. Much attention has been given to better understand these blooms but little effort has focused on why natural enemies (i.e., parasites and predators) do not restrict these rapid explosions in the populations of harmful algal species. The role of parasites in limiting algal blooms in the Great Lakes is particularly understudied, despite evidence that parasites, especially fungi, can play an important role in limiting algal population growth.

This project seeks to improve understanding of the influence of fungal parasites on harmful algal blooms in two ways. First, a field survey will be conducted using state-of-the-art molecular techniques to measure the diversity of fungal parasites of harmful algae and identify which species are most common and likely important. Second, a laboratory experiment with be conducted to examine how nutrients and temperature influence epidemics of parasites in algae, which should provide insight into how recent environmental changes in Lake Erie influenced these parasites.

The findings of this project will be useful in establishing the conditions under which parasites, a potentially important control on algal blooms, thrive and impact their host species. In addition, this work will greatly advance the research capacity at the University of Michigan to broadly examine the diversity and impact of algal pathogens in the Great Lakes. The project creates a freshwater collaboration on campus and enables a new, freshwater application of a faculty member’s expertise and that of a postdoctoral fellow.