Nutrients and Benthic Invasion Dynamics in San Francisco Bay

This project explores the consequences of nutrient pollution in San Francisco Bay on two mud snails. One is an invasive species, Ilyanassa obsoleta; the other is the bay’s only native mud snail, Cerithidea californica. Findings to date suggest that nutrients, at low levels, are a resource to the snails because the nutrients feed microalgae upon which the snails graze. At higher levels, a transition occurs and nutrients become harmful to the animals. That at least is the theory being tested. In a separate but related study, the fellow observed a sudden rise in the number of Batillaria attramentaria (a relatively new invasive mud snail) and is now studying the causes and impacts of its population explosion; the effectiveness of different eradication methods and their environmental safety will be tested.