Impact of Solar Energy on Anthopleura elegantissima and the Effect of Its Behavioral Defense Through Shell Coverage

The aggregating anemones, Anthopleura elegantissima, are often covered in varying densities of sand and broken shells in the tidal pools of Monterey, CA. It is unclear whether this shielding behavior protects anemones from predators or sunlight. However, because anemones have limited predation, solar protection may be a more probable explanation. Exposure to solar energy may be the source of multiple stressors for anemone at low tide, including extreme heat, desiccation, UV damage, and changes in air humidity. Therefore, in preliminary studies, we specifically focused on the relationships between full spectrum light exposure, anemone body temperature, and anemone desiccation. Individual anemones with and without shell coverage were exposed to UV light sources and thermistors were used to measure body temperature changes over the course of timed sessions. Sessions were visually recorded to document the reaction of anemone to light exposure. During timed trials in a lab environment, the anemone naturally exhibited typical low intertidal behaviors, such as contracting and releasing internal fluids. Additionally, anemones exhibited passive shielding during wave exposure but do not actively reach for shells. In future work, we aim to compare body temperature and weight data with amount of shielding in order to determine the effects of shell coverage on its body condition. Future atmospheric conditions may lead to shifts in UV radiation and heat stress, as well as changes to local climates; consequently, examining the adaptations intertidal organisms use to protect themselves from potentially detrimental temperatures is relevant.