A study of decontamination methods and controlling factors on the invasive algae Didymosphenia geminata in the Esopus Creek in New York State

Samantha M. Root, Bard College

Abstract/Artist's Statement

Didymosphenia geminata, commonly known as “didymo” or “rock snot,” is an invasive diatom (algae species) that lives in freshwater streams. Transported around the world by contaminated fishing waders, didymo is capable of spreading like a wildfire and forming huge blooms that cause millions of dollars in damages. Thus, it is imperative to understand both why didymo forms these blooms and how to reduce the further spread of this nuisance algae species. My project has three chapters: (1) a literature review about didymo, (2) a laboratory experiment that assessed three decontamination methods for didymo, and (3) a field experiment that aimed to predict what caused the presence of didymo in the Esopus Creek in New York State. Interestingly, I found that the three decontamination products I tested were not as effective as previous research suggested. I also found that the environmental factors we looked at in the Esopus Creek did not cause the didymo bloom; instead, fishermen’s movement patterns may the most likely cause of the nuisance blooms.