State marine biologists have tracked an electronic tag placed on a white shark in waters off Cape Cod last September to the coast of North Florida, providing clues to the wintering grounds and other habits of these top marine predators, Energy and Environmental Affairs (EEA) Secretary Ian Bowles said today.
Under a project led by Division of Marine Fisheries (DMF) Senior Biologist Greg Skomal, DMF biologists placed electronic tags on five great white sharks in waters off Chatham in September. At midnight on Friday, January 15, one tag surfaced 50 miles east of Jacksonville, Florida, and began transmitting data. The tag, which collects and records water temperature, depth and light levels to help scientists determine where a shark travels, will transmit data for several days using satellite-based technology.
"For Massachusetts citizens and biologists and shark enthusiasts across the globe, this is an exciting opportunity to study these fascinating creatures," said Secretary Bowles, whose office includes DMF, a division of the Department of Fish and Game. "We're looking forward to sharing the findings - so far, all we know is that this particular shark is a snowbird."
Over the next several days, Skomal - who heads DMF's shark research program - will analyze data transmitted by the tag looking for information about how deep and how far the shark traveled, which will allow scientists to better understand white sharks' migratory behavior. Additional tags may surface and transmit data later this winter and spring.
After multiple shark sightings off of the coast of Chatham last summer, Skomal and other state biologists set out to identify the species of the sharks off Monomoy Island in Chatham. Skomal, along with harpooner Bill Chaprales, captain of the fishing vessel Ezyduzit, placed the electronic tags on the sharks with the help of spotter pilot George Breen and Nick Chaprales, the boat's driver. This was the first successful tagging of white sharks in the Atlantic Ocean using electronic satellite technology. Click here for a video and photographs of the white shark tagging in September. "The information gathered from this tag will help to inform biologists about migratory paths and shark behavior, adding to the long list of DMF's contributions to the field of marine science," said DFG Commissioner Mary Griffin.
In 2004, the DMF attempted to electronically tag a great white shark that was stuck in a shallow embankment at Naushon Island off of Cape Cod. While DMF's Skomal was able to place a tag on that shark, the device detached from the animal shortly afterward without acquiring any data.
"Greg's scientific expertise combined with Billy's adept harpoon skills was a perfect combination. These ventures are typical of DMF's cooperative research with partners like those in the fishing industry," said DMF's Director Paul Diodati.
Many species of fish, including sharks, migrate to New England's coastal and open ocean waters in the summer months. At least a dozen shark species migrate in and out of New England waters annually. Massachusetts is the northernmost range for several species of sharks and is an important area for monitoring the health and distribution of shark populations. Although relatively rare in New England, great white sharks, are known to visit local waters, where they are sometimes seen feeding near seal colonies.
Last May, peer-reviewed journal Current Biology published Skomal's research on the migratory patterns of basking sharks. Using similar tagging technology, Skomal and his team documented the migratory habits of these large sharks, identifying previously unknown winter habitat - a discovery that has implications for the species' conservation. Click here to find out more about DMF's basking shark research.