Cooperative Agreement for CESU-affiliated Partner with Great Lakes National Forest Cooperative Ecosystem Studies Unit

The USGS is offering a funding opportunity to a CESU partner for research in development of slow release formulations of molluscicides. Zebra mussels (Dreissena polymorpha) and quagga (D. bugensis) are invasive freshwater mussels that significantly alter trophic structures and energy and nutrient dynamics in water bodies where they establish. Dreissenid mussels colonize the benthic zone of water bodies, degrading fish spawning habitat, and biofouling native mussels. Control tools for invasive mussels in open water are limited; two copper-based molluscicides, EarthTecQZ® and Natrix®, have been used in dreissenid control actions, but copper persists in the environment and is toxic to many nontarget organisms, including fish. Zequanox® is a biopesticide that is a relatively selective for dreissenids and rapidly degrades within 24 h of application; however, the current commercial formulation of Zequanox is a spray-dried powder which is difficult to apply to benthic zones for the required exposure duration without the use of benthic barriers. Niclosamide is also relatively selective for dreissenids, but similar to Zequanox, is not currently formulated for slow release in the benthic zone. This projects aims to develop one or more slow release formulations of a molluscicide (e.g., niclosamide, Zequanox) for use in open water applications to control dreissenid mussels.