Invasive Quagga Mussel: Potential Survival, Growth and Reproduction in a fresh to brackish water ecosystem

CARINA SEITZ; FACUNDO SCORDO; ERIN SUENAGA; SUDEEP CHANDRA

Grand Rapids

Congreso; Joint Aquatic Sciences Meeting 2022 in Grand Rapids, Colorado; 2022

American Fisheries Society (AFS) - Association for the Sciences of Limnology and Oceanography (ASLO) - Coastal and Estuarine Research Federation (CERF) - Freshwater Mollusk Conservation Society (FMCS) - International Association for Great Lake Research

Invasive dreissenid quagga and zebra mussels appeared in the Great Lakes Region of North America in the mid- 90s. In the last decades, quagga mussels dominated the westward expansion into select aquatic ecosystems and drainages. Studies evaluating invasion potential of quagga utilize physiological and life information large based on zebra mussel even though there are differences in the ecology of these species. We assess the survival, growth, and reproduction of quagga mussels in an ecosystem with a gradient of salinity (fresh to brackish) and pH (>8), and provide new insights on their tolerance to high pH concentrations. We observed 100% mortality after 12 h in brackish water (4 ppt, pH 9.3). In contrast, mussels were able to survive, grow, and reach sexual maturity after 57 days in freshwater (0.1 ppt) with a low calcium concentration (17 mg/L). In brackish water, swelling and disintegration of body tissues and high mortality rate suggested that the high concentrations of potassium, sodium, and chloride were the probable causes of death. Mussels died after two days at pH 11 and after ~12 days at pH 10— no mortality was observed at pH 9.0, 9.3, or 9.5 during 14 days of monitoring. The findings of this study provide new information about the upper limit of pH tolerance for quagga mussels. We agree with previous studies that increasing pH and K concentration are effective methods for eliminating adult mussel infestations. Examining invasion potential into aquatic ecosystems requires additional focus in understanding quagga mussel physiological and environmental tolerances.