Meeting Abstract
68.3 Monday, Jan. 6 08:30 Short-term exposure to elevated temperature and low pH alters mussel attachment strength NEWCOMB, LA*; CARRINGTON, E; GEORGE, MN; O’DONNELL, MJ; University of Washington; University of Washington; University of Washington; California Ocean Science Trust newcombl@uw.edu
Rising ocean temperature and decreasing ocean pH may impose physiological stress on organisms by affecting the material properties of structures that allow organisms to survive in a given environment. A mussel’s ability to form strong byssal threads to attach themselves to substrate is crucial for their survival in a hydrodynamic environment. The combined effects of ocean warming and acidification (decrease in pH), may decrease mussel attachment strength and thus their ability to survive. Threads are comprised of three functionally distinct regions acting in series, therefore the ability of multiple stressors to work in tandem with each other is dependent upon the region they affect. Our previous work demonstrated elevated temperature weakens all thread regions while low pH only affects the adhesive plaques. We tested the hypothesis that at high temperatures, temperature is responsible for thread weakening with minimal effects of pH, and at cooler temperatures, low pH conditions will weaken threads. Field collected mussels (Mytilus trossulus) produced threads in temperature and pH controlled aquaria for three days. Temperature and pH did not have additive effects on byssal thread strength, rather, depending on the given temperature and pH, one of the stressors dominated. Temperature had a greater effect than pH on byssal thread strength under the conditions measured; mussels produced 2.7 times fewer and 2.7 times weaker threads at 25C in comparison to 10C. Low pH led to a slight increase in plaque strength in the lower temperature treatments. Short-term exposure to elevated temperature and low pH is enough to cause changes in byssal thread material properties suggesting mussel attachment may be impacted by future predictions of ocean change.
