Publication Date

Fall 2022

Degree Type


Degree Name

Master of Science (MS)


Moss Landing Marine Laboratories


Jonathan Geller

Subject Areas



The intertidal zone is a stressful environment with one of the main stressors being the fluctuation of wave energy over time and space. A structural adaptation employed by mussels living within the intertidal zone is byssal threads that aid in attachment while dealing with various levels of wave exposure. The California mussel, Mytilus californianus, lives in extremely wave exposure conditions, which makes it a great study species to assess the relationship between wave intensity and byssal thread strength. In this study, Mytilus californianus were collected from two locations in the Monterey Bay, each with a predicted wave exposed site and a wave protected site. The dimensions of the byssal threads were recorded and the threads tensile strength were measured on a tensometer. Thread strength and thickness werehigher at the wave exposed site in Santa Cruz compared to the wave protected site. At the other location, Pacific Grove, there was no difference between the predicted exposed and protected sites, but thread strength and thickness increased over time, mirroring seasonal changes in wave energy. These results support the relationship between wave intensity and thread strength and thickness over space and time, but the response to variable wave intensity is not consistent at both locations. A more accurate wave intensity assessment for individual mussels would be helpful to determine the intricacies of this relationship moving forward.