[MARINE_BIOLOGY_INTERNATIONAL] Mote scientists tag great white shark off Cape Cod


Mote scientists tag great white shark off Cape Cod

Associated Press and Herald-Tribune staff

Tuesday, September 18, 2012 at 6:19 p.m.

CHATHAM, Mass. - The scientists and fishermen on board the Ocearch, a repurposed crabbing vessel, received word that their scouting boat had hooked a great white shark, sparking a flurry of activity. The crew, which included researchers from Sarasota's Mote Marine Laboratory, were about to get up close and personal with the animal, more than 2,000 pounds and nearly 15 feet long during an expedition last week.

Shark scientists fitted the great white — nicknamed Genie after Mote Marine Laboratory founder Eugenie Clark — with a satellite tag to follow her journeys and an accelerometer to see how she moves through the water. Adding the accelerometer was a scientific first for an Atlantic great white.

Protecting these sharks is key to maintaining ecological balance between top predators and smaller species, researchers say.

"These predators keep the next lower level in check," said Bob Hueter, of Mote Marine Laboratory, one of the research organizations working with the Cape Cod expedition. "It's a system of checks and balances."

Mote's accelerometer recorded the shark's graceful and balanced movement through the water for about 10 hours, giving scientists insight into how the magnificent sharks swim.

Ocearch's real-time satellite tags work for five years. Each time a shark's dorsal fin breaks the surface, the tags ping a satellite and mark an online map, accessible to researchers and the public.

Just after dusk on Sept. 13, the crew spotted the great white and hooked it. Then, the small boat's crew slowly led the shark four miles to the 126-foot Ocearch.

Ocearch Capt. Brett McBride guided the shark onto a wooden platform with metal sides. Barefoot, he jumped in too. The lift slowly rose out of the water, bringing it level with Ocearch's deck.

The shark thrashed and bared her teeth as the water receded, curving her head and tail into the air.

McBride threw a wet towel over her eyes and removed the two-foot hook from her mouth. He pumped water over her gills with two large hoses.

The crew jumped onto the lift in their jeans and long-sleeve shirts, and the clock began.

They measured the fish and screwed the satellite tag, the accelerometer and an acoustic tag onto her dorsal fin with a power drill. Researchers collected blood and tissue samples.

McBride grabbed Genie's tail and slowly guided her back into the ocean. They were done in 16 minutes. Genie drifted down into the dark water.

The new tags deployed on Genie will help uncover great white movement patterns and potentially reveal vital habitats where they mate and give birth.

"That one shark alone was worth the trip," McBride said, noting she might lead researchers to breeding and birthing sites. "Any time we tag a great white shark it adds tremendous information to what we already know, which is very little."

Genie has already pinged several times in the waters off Nantucket.

Herald-Tribune staff writer Kate Spinner contributed to this report.

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