It’s the peak of shark fishing season, when
hundreds of fishermen enter tournaments throughout southern New England and
Long Island to catch the biggest shark in nearby waters. And it has BradleyWetherbee worried.
The
University of Rhode Island shark researcher knows that one mako shark he tagged off the coast of
Maryland last year – which a sponsor named Charlotte – arrived in Rhode Island
waters last week after a year-long, 6,500 mile journey. And given his track
record of having his tagged sharks captured and killed by commercial and
recreational fishermen, Wetherbee has his fingers crossed that Charlotte
survives the month.
“Makos
are caught in all kinds of fisheries all around the world,” he said. “They’re
the shark everyone wants to catch because they’re good to eat – like a shark
version of swordfish – and they fight and jump and put up a big battle.
“But
it takes a great deal of effort and money to catch and track sharks, and we
don’t want to see our research subjects captured and killed and lose their
contribution to science,” he added.
Wetherbee
doesn’t object to shark fishing. In fact, his research is aimed at collecting
information about the animals so they can be better managed and available for sustainable
harvest for many years to come. He just hopes that any fisherman who catches
Charlotte or any other shark with a satellite tracking tag on its fin will
release the shark back in the water unharmed.
Little
is known about the health of mako shark populations, the migratory routes they
travel, or their preferred feeding grounds. Wetherbee hopes his research will
help to answer some of these questions. Makos are especially difficult to
manage because they travel through the waters of dozens of countries, thereby
requiring significant international cooperation to protect them from
overfishing.
Shark
fishing isn’t the only threat to mako shark populations, however. The demand in
China for shark fin soup is causing 70 million sharks to be killed each year
for their fins. And while little shark finning takes place in New England
waters, mako sharks have a worldwide distribution, so they are among the most
commonly captured shark in the finning trade.
Wetherbee
and his colleagues at the Guy Harvey Research Institute at Nova SoutheasternUniversity have tagged more mako sharks in the Atlantic Ocean than any other
scientists. The satellite tags they attach to the sharks’ fins enable the
researchers to track the animals’ movements from day to day, which is how
Wetherbee knew exactly when Charlotte arrived back in Rhode Island waters. It’s
also how he knows that nearly a third of the 50 mako sharks he has tagged in
recent years have been caught and killed by fishermen.
“It’s
easy to see the track lead right to a port somewhere and the tag just ends up
sitting on a dock,” he said.
The
data Wetherbee is collecting from his tagged sharks is providing estimates of
mako shark mortality that are far higher than scientists once believed.
“So
it’s possible that they are being overfished much more than previously
thought,” Wetherbee said.
His
tagged sharks have moved through the waters of 27 countries. One shark traveled
14,000 miles in one year, and many have traveled more than 10,000 miles.
Charlotte’s route took her from Maryland to Virginia, then north to Rhode Island
and Long Island, where she spent several months last fall. She then returned south to North Carolina
before going on a two month loop far out into the Atlantic in April and May.
She returned to south coastal waters in June, and then traveled to Rhode
Island, where she arrived last week.
“It’s information that no one had any idea
about – their movements, how much time they spend in the north in winter, the
countries they visit,” Wetherbee said. “It’s generating a lot of great
information that is useful for managing shark populations.”
The
URI scientist said that Charlotte is obviously unaware of the risks she is
taking by arriving in Rhode Island waters at this time.
“She’s
running the gauntlet,” he said. “There are three shark fishing tournaments just
in tiny Rhode Island, and many more in Massachusetts and Long Island. There are
hundreds of boats out there that would like to kill her and eat her. And if she
makes it up to Canada, that’s where the longline fishery takes place. That’s
another place she could easily get caught.
“If
I were Charlotte’s parent, I’d be crossing my fingers that she makes it out of
here alive,” Wetherbee said.
Monitor the movements of Charlotte and the other sharks Wetherbee has tagged here.
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