ABSTRACT
Zebra mussels are an invasive species that have infested many bodies of water, including
Texas lakes and streams. They cause billions of dollars in infrastructure damage by clogging
pipes and water intakes. They also have a significant ecological impact on aquatic ecosystems
and native species. Zebra mussels can spread as adults by attaching to commercial boats or as
planktonic larvae via water flow through lakes and rivers. Several methods are used to help
prevent the spread of zebra mussels. Heated water, chlorine, and copper are currently used to
help control the spread through pipes in factories and water treatment facilities. One promising
copper solution, Earthtec QZ, was designed to treat algal blooms but was recently found to kill
mollusks. The exact effectiveness of Earthtec QZ on eliminating zebra mussels is unclear. This
project examines the effects of copper treatment on both adult zebra mussels and the
developmental stages including gametes and fertilization. Adult mussels of varying size classes
were exposed to different concentrations of Earthtec QZ to determine mortality rates. In another
experiment, eggs and sperm were exposed to the copper treatments to determine its effects on
fertilization. A third experiment tested chlorine concentrations previously found to kill veligers
as an alternative.