Big Tracks, Surprising Findings from 2015 Shark Tracking Project

February 19, 2016 at 1:32 am | Posted in Uncategorized | Leave a comment
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GHRI 2015 All TrackingBy Sue Cocking, Guy Harvey Outpost staff writer

scocking@guyharveyoutpost.com

The yellow, green, pink, and white dots and blobs on this Google Earth graphic cover such a large portion of the globe that it is difficult to show the entire picture.  And that means a heck of a lot to marine scientists like Drs. Guy Harvey, Mahmood Shivji, and Brad Wetherbee of the Guy Harvey Research Institute at Nova Southeastern University near Fort Lauderdale.

The dots and globs represent the paths of some 40 sharks rigged with satellite tags that the scientists tracked in 2015:  three tiger sharks (green); 20 makos (yellow); seven oceanic whitetips (pink); and one dusky, four hammerheads and a sixgill (white and barely visible off Boca Grande, FL and Bermuda).

“Pretty impressive.  A huge part of the ocean,” noted Wetherbee of the sharks’ movements.

Satellite tags, which cost upwards of $4,000 apiece, are technology’s most precise method of monitoring the animals’ movements minute to minute.  Funded by the non-profit Guy Harvey Ocean Foundation, the transmitters are affixed to the sharks’ dorsal fin, sending their locations to a satellite that beams the information to the researchers’ computers.  Wetherbee then plots that information on Google Maps.

What this worldwide splash of color represents is a blueprint for protecting sharks from habitat loss and overfishing. And the tracking data has turned a few shark theories on their heads.

According to Wetherbee, tiger sharks– previously believed to be a coastal species– are nothing of the kind.  The data shows they spend half their time in the open ocean thousands of miles from shore, but in winter show a snowbird-like affinity for coral reefs in the Caribbean and Bahamas.  One tiger nicknamed Harry Lindo covered 27,000 miles– the longest distance ever tracked for the species.

Mako sharks seem to stick to the open ocean– cruising the edge of the Continental Shelf off the U.S. east coast then making long trips north to New England and Canada.

The oceanic whitetips tend to wander around aimlessly, though whatever they’re doing isn’t aimless to them– sort of like a bee flying over fields and alighting on several flowers in one field but totally ignoring those in another.

The makos and whitetips were named competitors in the Great Shark Race of 2015 created by the Guy Harvey Ocean Foundation and Research Institute to encourage businesses and individuals to sponsor satellite tags.  The shark covering the greatest distance in six months– a shortfin mako named Ebenezer that swam 7,387 miles–was declared the winner.  Ebenezer– named by Ebenezer Thomas Primary School in Tortola, British Virgin Islands– was sponsored by Sir Richard Branson’s Virgin United.  It was tagged off Ocean City, Md. on May 27, made it to Newfoundland in the allotted time, and is still transmitting.

GuySRB

Unlike those free-swimming makos and whitetips, Wetherbee noted that hammerheads tend to stick to coastlines in the U.S. and avoid long-distance travel.  Sixgills, he said, stay in deep water and don’t go very far while duskys seem attached to certain sites, but still may travel a few hundred miles.

“There are sharks without a country, moving through 10 to 15 different countries,” Wetherbee said. “They are all over the place.”

The research has important implications for shark management:  knowing what countries’ waters the sharks use suggests who is responsible for managing that population and where the animals are most likely to be harvested by fishers.

“Shark populations have been overfished quite a bit.  Managing these populations is going to take international cooperation,” Wetherbee said.

Mako sharks, while not classified as overfished, could still be in trouble as they are heavily targeted by commercial longliners and recreational anglers in the U.S. and elsewhere.

“Makos are in a lot of areas with tuna and swordfish,” Wetherbee said.  “Everybody is after these makos because they are good to eat.”

Indeed, 13 of the 49 makos tagged by the GHRI scientists over the past four years have been caught and killed by commercial fishers.  The tiger sharks, fortunately, escaped those gauntlets.

Wetherbee, Harvey and Shivji plan more shark-tagging expeditions in 2016, hoping to fit another 40 to 50 animals with satellite transmitters.

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Sue Cocking chronicles the Guy Harvey Outpost travel and adventure experience in regular blog posts on GuyHarveyOutpostNews.com/.  For 21 years, Cocking covered the full spectrum of outdoors adventure opportunities in South Florida and beyond for the Miami Herald, including fishing, diving, hunting, paddling camping, sailing and powerboat racing.  She is a certified scuba diver and holder of an IGFA women’s world fly fishing record for a 29-pound permit.

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Diving Thrills with Huge Fish at Guy Harvey Outpost in Mexico

September 25, 2015 at 3:03 pm | Posted in Uncategorized | Leave a comment
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makodredge1 (2)By Sue Cocking, Guy Harvey Outpost Staff Writer

scocking@guyharveyoutpost.com

It looks just like a giant, wide-open front-end loader plowing the surface of the Caribbean Sea, except it’s ALIVE.  A 15-foot long whale shark — one of hundreds that gather annually from June through mid-September in the waters around Isla Mujeres, Mexico–is sucking up its dinner of plankton as a horde of enthralled snorkelers hovers nearby to watch.  The calm, placid giant– broad and brown with white dots– pays them no mind and cruises slowly along, feeding on the spawn of bonitos with its huge dorsal fin sticking up out of the water.  A few feet away, a six-foot- wide manta ray joins the buffet line, and the snorkelers’ heads swivel wildly back and forth.

The waters around this small island just off Mexico’s northern Yucatan peninsula are one of very few places in the world where just about anyone can get close-up and personal with the largest fish in the ocean in its natural environment.  And captain Anthony Mendillo of Keen M Blue Water Charters is your best choice for tour guide.

One of the region’s pioneering whale shark tour operators, Mendillo zealously protects these charismatic creatures and delights in introducing them to visitors.

“The whale shark dive is so cool because the whole family can enjoy it,” he said.  “Children can go.  You don’t have to be a professional diver or a professional naturalist to appreciate the magnitude of the experience.”

Indeed, the Mexican government prohibits scuba diving with the whale shark aggregation; only mask, snorkel and fins are allowed.  Visitors are not permitted to touch the animals or use flash photography.

Although the 2015 whale shark season has wound down, Isla Mujeres and Keen M offer other unique topwater and underwater opportunities:  snorkeling with sailfish and cage-diving with mako sharks.

From January through early March, Keen M boats escort their customers to the catch-and release of up to 50 sailfish per day on rod-and-reel  by homing in on seabirds diving on schools of sardines that form tight bait balls.  After everyone’s arms are worn out from reeling in sails and letting them go, it’s time to jump in and check out the spindlebeaks’ living room.

“I have people who catch a double and now they’re down there in their underwear ready to jump in,” Mendillo said.  “It’s a very happy medium when a guest can say, ‘I saw a sailfish eat a sardine; now I know how to hook them.'”

The occasional wahoo has been known to join the sails in crashing the bait balls, adding to the excitement.

For the extremely adventurous, Keen M offers cage-diving with mako sharks that cruise the region in March and April.  If you go, you just may spot a mako sporting hardware on its dorsal fin.  That’s because Guy Harvey and colleagues from Nova Southeastern University Oceanographic Center have implanted several with tags to track their movements.

Your headquarters for diving and fishing in Isla Mujeres is the Hotel Playa Media Luna, a Guy Harvey Outpost Expedition Lodge.  There are plenty of openings for 2016.

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Sue Cocking chronicles the Guy Harvey Outpost travel and adventure experience in regular blog posts on GuyHarveyOutpostNews.com/.  For 21 years, Cocking covered the full spectrum of outdoors adventure opportunities in South Florida and beyond for the Miami Herald, including fishing, diving, hunting, paddling, camping, sailing and powerboat racing.  She is a certified scuba diver and holder of an IGFA women’s world fly fishing record for a 29-pound permit.

Massive Mako Surprises Diver and Blue Marlin During Guy Harvey Expedition in the Bahamas

July 18, 2012 at 4:10 pm | Posted in Bahamas, Guy Harvey, Guy Harvey Outpost Ltd., Marine Science, Sharks | Leave a comment
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You never know who will show up on a Guy Harvey Expedition! In this video, a massive 10 ft. long, 600 lb. mako breaks the underwater silence when it rockets past the camera as it stalks a blue marlin!

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