Why is it so cool? Monitoring Sand Crabs is a great way to review the scientific method we learned at the beginning of the year while racing turtles and have utilized in lab activities throughout the year. ALSO... The data is valuable on a national level! Sand Crabs are an indicator species, their population, or lack of population, can indicate the health of the environment, particularly water quality. The unique way that they feed (filter feeding) collects pollution, as a result they tend to experience severe population losses in response to poor water quality. Collecting this data over a long term period (over 10 years, seeing as I did it in high school!) is useful in mitigation from oil and sewage spills!