Scientists have discovered that several crab species, including those not usually found on floating objects, are using sea snakes as a means of transportation across the ocean. This finding, published in the journal Ecology and Evolution, was led by marine herpetologist Joseph Pfaller. During a research trip off the coast of Costa Rica in 2012, Pfaller first noticed crabs clinging to sea snakes. Having previously studied sea turtles and the organisms that live on them, Pfaller identified these crabs as megalopae—tiny, early-stage crabs that are in between their larval and adult forms. The study found these megalopae, along with juvenile crabs, on 371 sea snakes collected during the research. The crabs identified were mainly from the Grapsidae family, which includes species like the Sally lightfoot crab, the racer mangrove crab, and the mottled shore crab. These crabs are typically found near shorelines, not in open ocean waters. However, their megalopae were found on sea snakes, which spend much of their time in open water. Researchers suggest that the crabs may be mistaking the sea snakes for floating debris, a common way for some marine organisms to travel. This kind of transport helps them reach new habitats, such as shorelines where they can grow and mature. The study also looked into whether crabs from the genus Planes, known for attaching to floating objects, might be found on sea snakes. However, no Planes megalopae were identified. Sea snakes were found to be less suitable for crabs compared to sea turtles, which offer a more stable surface for these organisms. The researchers believe that crabs in the Grapsidae family may have evolved to climb and attach to floating objects, which could explain their presence on sea snakes. This research highlights the intricate relationships between marine species and their environments. It shows how even small organisms can have complex strategies for survival and movement in the ocean. The findings contribute to our understanding of how marine life interacts with the vast and dynamic open ocean.