— Written by Emma Saas

Kelp washed up on shore, providing resources for many sandy beach invertebrates

The California coast is world famous for its miles of sandy beaches, sunbathing, beach volleyball, and morning jogs along the water line. Each year, millions of tourists come to enjoy what this state’s shorelines have to offer- and why wouldn’t they? Watching sunsets in bathing suits after a long day of surfing sounds like a pretty postcard worthy vacation. What many tourists -and locals!- don’t always think about,is the fact that beaches are also rich coastal ecosystems. Food webs on beaches depend on subsidies from other marine ecosystems, like kelp forests. On many tourist beaches, beach grooming removes washed up kelp and other organic material from the beaches using large machines. Kelp is food and shelter for many important invertebrates including talitrid amphipods, commonly known as beach hoppers that look like little jumping shrimp.

Megalorchestia corniculata, a talitrid amphipod, begins burrowing into the sand

Several species of beach hoppers are commonly found on southern California beaches including Megalorchestia corniculata, M. californiana, M. minor, and M. benedicti. All four of these highly mobile crustacean species burrow into the damp sand near the high tide line and emerge to feed on kelp, damp paper, and even cardboard after dark. As vital parts of the beach food web, talitrids are preyed upon by birds and other animals. They are most active at night to avoid becoming an afternoon snack! Deep damp burrows create a cozy place for talitrids to remain safe and out of sight all day long. Unfortunately, widespread destructive practices, such as beach grooming disrupt their burrowing, shelter, and food supply.

Picture of an adorable talitrid amphipod for good measure

This wealth of unique intertidal life found on ungroomed beaches begs the question, what is a pristine sandy beach?  The definition of ‘pristine’ has to cease to be ‘empty combed sand’, and instead turn into ‘healthy ecosystems rich with life’. Global warming threatens our sandy beaches with rising sea level and higher temperatures, beach grooming mechanically removes sustenance and habitat, and humans need to truly realize our impacts on the places we love. For as much as we love our sandy beaches, we do not want to love them to death.