Oil? Spills? and Crabs? Oh my!

How did the 2007 oil spill in the San Francisco bay affect the population of sand crabs in the area? This question is important because sand crabs are significant to beach ecosystems; they are food for many animals, and they are also an indicator species. This means that scientists and researchers can look at sand crabs to determine the health and sustainability of beaches and other marine ecosystems. More

Crabtivating Sand Crab Distribution at Playa Del Rey Beach

Cleo, Jerome, Kate, and Gloria
Bishop O’Dowd High School

No need to feel clawstrophobic (or get crabby), there is plenty of room for all the sand crabs on Playa del Rey Beach! So, how has sand crab population changed over time on this Southern Californian beach? This question allows us to further understand the Southern California sand crab population.
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What about the Children?

Sand crabbingGianna, Jack, Peter, and Nathan
Bishop O’Dowd High School

After going on a trip to Ocean Beach in San Francisco and gathering data about the local sand crabs, we wondered how many of them were “recruits,” little crabs which are new to life on the beach. How does this number change over time? Once a recruit settles on a beach, it will spend the rest of its life there. So, a healthy recruit population means that there will be a healthy adult population in the future (unless there is an environmental hazard). As long as there are no environmental hazards or strange weather conditions, the portion of recruits can be used to predict future sand crab growth and decline.
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Battle for the Beach-Crustacean Nation

by Miles, Sophia, and Charlie
Bishop O’Dowd High School

A sharp, cold wind rips across the beach, chilling the shivering O’Dowd students to the core. But there is no room for weakness. The research must be conducted at any cost. As the oceans continue to be examined, the relationship between sand crabs and sanderlings remains unclear. The two species are locked in the age-old, evolutionary battle of predator and prey, but the other aspects of their interactions are unknown. Exploring the correlation between the abundance of sand crabs and the abundance of shorebirds on Ocean Beach is a key component of understanding the beach as a whole. This research is vastly important, as sand crabs act as prey for many species on the sandy beaches, and serve as an indicator species, or a species that serves as a gauge for a habitat’s health.
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Itch for Crabs? (Not those crabs!)

Mole crabby Brian, Somari, and Charles
Bishop O’Dowd High School

Have you ever looked down while at the beach, and seen tiny creatures rolling around, and live in the sand? These tiny creatures are called sand crabs and they are quite paramount to their ecosystem. You may be wondering why sand crabs are so important and it is because they are prey for many animals such as shorebirds and fish. As a species, they can determine whether or not the ecosystem will be healthy. sand crabs make up 80-90% of the intertidal invertebrate biomass. Males and females vary in sizes but the females tend to be larger.
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