Meeting Abstract

P2.187  Monday, Jan. 5  Thermal Tolerances of the Invasive Mussel Mytella charruana BRODSKY, Sasha*; WALTERS, Linda; HOFFMAN, Eric; SCHNEIDER, Kimberly; University of Central Florida sashab367@yahoo.com

Mytella charruana is an invasive bivalve that, in the past five years, has been found fouling docks and oyster reefs on the southeastern Atlantic coast of the U.S. It originates from both coasts of South America. We have been trying to better understand this species by studying its physiological tolerances. We first tested M. charruana‘s cold temperature tolerances. In 14-day trials, salinity ranged from 9-15 ppt based on the collecting site. We started out using 6, 13, and 20C water. 20C was the baseline because this was the temperature at which we collected mussels. There was no survival at 6C, but significant survival at 13 and 20C (58 and 41%, respectively). So we tested a narrower range of temperatures (6, 9, 11, and 13C). All M. charruana died at 6C, but survived at 9, 11, and 13C (12, 13, and 31%, respectively). These trials were carried out using 5-day adjustments between temperature treatments. Next, we conducted a shock temperature trial. All mussels were immediately placed in 6, 9, or 11C from 20C water. Six hours later, the temperature was adjusted back to 20C. At 6C, there was low recovery (12%), but at 9 and 11C (66 and 71%, respectively), M. charruana had a high recovery. Warm temperature trials are currently underway, with one trial completed. 20, 23, 28, and 31C waters were tested using 5-day adjustments between treatments. There was little mortality at any of these temperatures, so a new trial is underway with 20, 31, and 36C treatments. Once a maximum temperature for survival is known, shock trials will be run. We have determined the thermal minimum for M. charruana (6C), and hope to soon know its thermal maximum. This information can help us predict where this invader may spread in the future.