Description
Due to climate change and resultant sea level rise our planet is suffering from increasing rates of coastal erosion. To preserve sandy beach ecosystems and mitigate coastal erosion, beach replenishment projects have become widespread. However, sediment obtained for beach replenishment often does not match the beach's original sand. Altering a beach's original sand may negatively impact the organisms that live in this ecosystem. One organism that is an important component of California's sandy beaches is the Pacific mole crab, Emerita analoga. For my research I used a controlled lab study to examine how mole crab burial time and burial amount (amount of body that was buried), were impacted by sediment grain size and which beach individuals were collected from. To determine burial time and amount burial, the individual burial trials of one-hundred mole crabs, collected from two San Diego beaches, were digitally recorded in both fine and coarse sand. Fifty subjects were collected from each of the two beaches, WindanSea Beach, La Jolla and Mission Beach. Digital video analysis identified trends that mole crabs burrow faster in the sand type consistent with that of the beach they were collected from. Trends also identified that individuals collected from both beaches burrow more completely in coarse sediment as compared to fine. These results indicate that altering a beach's native sand type through beach replenishment projects can have a negative effect on mole crab burrowing abilities, and ultimately may impact survival and risk of predation.
The Effects of Sediment Grain Size on Burial Rates of the Pacific Mole Crab, Emerita Analoga
Due to climate change and resultant sea level rise our planet is suffering from increasing rates of coastal erosion. To preserve sandy beach ecosystems and mitigate coastal erosion, beach replenishment projects have become widespread. However, sediment obtained for beach replenishment often does not match the beach's original sand. Altering a beach's original sand may negatively impact the organisms that live in this ecosystem. One organism that is an important component of California's sandy beaches is the Pacific mole crab, Emerita analoga. For my research I used a controlled lab study to examine how mole crab burial time and burial amount (amount of body that was buried), were impacted by sediment grain size and which beach individuals were collected from. To determine burial time and amount burial, the individual burial trials of one-hundred mole crabs, collected from two San Diego beaches, were digitally recorded in both fine and coarse sand. Fifty subjects were collected from each of the two beaches, WindanSea Beach, La Jolla and Mission Beach. Digital video analysis identified trends that mole crabs burrow faster in the sand type consistent with that of the beach they were collected from. Trends also identified that individuals collected from both beaches burrow more completely in coarse sediment as compared to fine. These results indicate that altering a beach's native sand type through beach replenishment projects can have a negative effect on mole crab burrowing abilities, and ultimately may impact survival and risk of predation.