The effects of fluctuating temperature and pH on the shell and radula morphology of the pinto abalone (Haliotis kamtschatkana)

Overharvesting of the pinto abalone (Haliotis kamtschatkana) caused severe population declines leading to the classification of endangered by the WDFW. Efforts to help the pinto abalone recover by outplanting juveniles at specific sites around the Salish Sea are ongoing. Survival of outplanted individuals is different at each site, but it is not clear why. Differences in water quality conditions, such as temperature and pH, could explain the differences in survival. The goal of my thesis was to simulate in lab the outplanting of abalone in fluctuating temperature and pH conditions. I hypothesized that temperature fluctuations and low pH will negatively affect the pinto abalone, such that there will be a higher number of shell and radula deformities and decreased survival and growth under these conditions. Under static temperature conditions, pH did not affect survival, however, under fluctuating temperature conditions, survival was negatively affected by high pH. Fluctuating temperatures yielded higher growth, determined by mean shell length, while low pH yielded lower growth. Shell morphology exhibited a similar pattern to growth. Radula morphological analysis is ongoing. The finalized results of this study will aid in selection of outplant sites by recommending water quality conditions which promote survival and proper development.