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Under the Sea Science Projects on Sharks

Despite their reputation, sharks are less dangerous to humans than you might imagine; only a handful of shark attacks take place each year. Nonetheless, their size and sharp teeth make these sleek swimmers an object of lasting fascination. Moreover, as predators situated high up in the food web, they are crucial to the health of many ocean ecosystems. Scientists have devised a number of clever ways to study these elusive animals. The following are just a few of the more interesting science projects on sharks.

Sex-Biased Dispersal of Great Whites
- The great white shark, Carcharodon carcharias, is one of the ocean's largest predators; while rare, it roves the continental shelves of temperate waters around the world. In a 2001 paper published in the journal Nature, some scientists found an interesting pattern of migration among great whites in the Indian Ocean. The researchers compared nuclear DNA, which is inherited from both parents, and mitochondrial DNA, which is inherited from the mother only, between two populations, great whites off of South Africa and great whites off of Australia and New Zealand. Their results suggested that there was relatively little exchange of female great whites between the two populations, but that male great whites interchanged between the two populations quite frequently.
NMFS
- The National Marine Fisheries Service has a program to tag sharks in the Atlantic Ocean. When sharks are caught by volunteer fishermen or biologists, plastic tags can be inserted through or near the base of the dorsal fin. If anyone should later recapture and re-release the same shark, they can then inform the NMFS and thereby provide data on the movements of that shark. The ultimate goal of the program is to learn more about shark migration and movement patterns.
PAT
- Pop-up archival tags are a recent development in ecology that have made it much easier to learn about the movements of wild animals. These tags are similar to more conventional plastic tags but contain a microchip that stores data on the depth, temperature and light levels of the shark's surroundings. At a predetermined time, the PAT frees itself from the shark and floats to the surface, where it begins transmitting info by satellite. Pop-up archival tags have been used to study great whites and thresher sharks (among others).
Whale Shark Tracking
- The ECOCEAN Whale Shark Photo-Identification Library is a virtual archive of whale shark photos taken by divers. The skin patterns behind the gills of each shark can be used to distinguish individuals, much like different fingerprints among people. By uploading photos of these patterns, the library can track the movements of individual whale sharks to learn more about their migration patterns and population structure. Any diver with photos can submit them to the library, which is maintained by marine biologists. Some 3,259 sightings were reported to ECOCEAN in 2009.

Nature