Marine Heatwaves and the Intertidal Zone

Since the beginning of the 20th century, there has been an increase in both the duration and frequency of marine heatwaves (MHW). A marine heatwave is a time period of abnormally high temperatures in the seawater that can last for a few months to a few years. These events have had a serious impact on the destruction of marine environments. Specifically, beginning in 2014  

there was a MHW that persisted until 2016 along the western coast of the United States, the event became known as ‘The Blob’. Little research has been conducted to determine how MHWs affect intertidal organisms, specifically mussels. Using long-term data collected by Partnership for Interdisciplinary Studies of Coastal Oceans (PISCO), Multi-Agency Rocky Intertidal  Network (MARINe) and the Helmuth lab, I performed a time series analysis to determine the impacts of The Blob on California mussels (Mytilus californianus) temperatures and settling populations.  

I examined two sites in Santa Barbara, CA (Lompoc Landing and Coal Oil Point).  Annual average temperature and daily averages were collected in order to examine and compare the elevated temperatures to the baseline temperatures. For Lompoc Landing, in 2015 the annual average temperature and the daily average temperature increased by 1.7 ℃ compared to the baseline. In the same year, for Coal Oil Point annual average temperature increased by 2.6℃  compared to baseline, and increased by 2.2℃ over the baseline daily average temperature during the years of The Blob. The settlement data is being analyzed. Due to their vulnerability to temperature in the environment and their importance to the intertidal ecosystem, California mussels make a good specimen to study. This research is important, as it focuses on addressing the critical gap in knowledge of how intertidal organisms are affected by marine heatwaves.