It’s mid-summer,
people are flocking to the beaches and just about everywhere, especially during
a popular week on cable television, there appears to be a fascination with
sharks.
But for Brad
Wetherbee, a biology lecturer in the University of Rhode Island College of the
Environment and Life Sciences, his fascination with sharks isn’t a seasonal
thing. He has been interested in the creatures for years, actively trying to
solve some of the mysteries surrounding these swift predators that have long
been feared by swimmers and embraced by filmmakers.
During the school semesters, Wetherbee teaches biology and marine biology to hundreds of undergraduates. But during the summer and sometimes during semester break, he is employed by a research institute that needs him to help them track sharks and other mysterious denizens of the deep.
It all started at the
University of Hawaii where he earned his doctorate. The university had a
program tracking sharks with acoustic transmitters. The devices had severe
limitations — researchers had to stay close to the sharks because the range and
reliability of the transmitters left a lot to be desired.
In the late 1990s,
however, new tracking devices that could communicate with satellites were
developed and so wholesale tracking programs were possible on a host of marine
creatures such as bluefin tuna. There evolved two basic devices — those that
could communicate when the creatures came to the surface and those that would
automatically pop up to the surface in the case of marine life that rarely
surfaces.
Once the signals are
transmitted to satellites, triangulation determines the creature’s exact
coordinates.
It’s a system that is better than the acoustic devices of years ago but it is not without practical problems, especially when it comes to sharks, which are always on the move.
It’s a system that is better than the acoustic devices of years ago but it is not without practical problems, especially when it comes to sharks, which are always on the move.
“If we try to get the
devices on the fish for a long time, we bolt them on and then you are lucky if
they stay on as long as the batteries last,” Wetherbee said. “So many things
can go wrong. It’s a big battle.”
A sole AA battery
powers the devices.
But the battle is
worth the challenge, because the researchers are finding some surprising things
about certain species of sharks — there are 500 of them in all. Wetherbee
and other researchers are fascinated with the travels of tiger sharks. It was
once thought that these powerful sharks were coastal dwellers, but the tracking
studies show they swim thousands of miles out into the Atlantic for half the
year before returning to warmer climes in the Bahamas.
“It’s surprising how
much time tiger sharks spend in the open ocean,” Wetherbee said. “We now know
where they go but we don’t know why. Tiger sharks are hard to figure out. They
don’t like to conform.”
The lack of conformity
is also surprising. “Half the year they are coral reef fish and the other half
is spent in the open ocean. That’s like some animal that spends a half year in
a rain forest and the other half in a desert,” he said.
Wetherbee does the
tracking for the Guy Harvey Research Institute in Florida. Guy Harvey is an
entrepreneur who has a doctorate in marine biology and offers a whole line of
marine products from T-shirts and swim wear to original paintings. “He’s a
conservationist who sells things to support his research institute,” said
Wetherbee, who has been working with Harvey for 13 years. “He’s keen on giving
something back.”
On the institute’s website,
visitors can watch various types of sharks and the routes they have traveled
the past few years. The institute is now tracking 16 sharks and the data comes
in constantly, according to Wetherbee.
He has students, some
paid and some get credit, to help him log the data. “It’s good all around as it
helps me get away from some tedious work and gives them some experience doing
research,” he said. “Of course they are not out there tagging sharks, which
they would love to do.”
Wetherbee has taken
some students with him to tag sharks on occasion — even his young
daughter.
All of the expenses in
the tracking operation are paid by Harvey. The tracking devices themselves cost
$5,000 for the pop-up types and $2,000 for those bolted onto a shark’s dorsal
fin. On top of that are expenses for crews, boats and satellite usage fees —
that’s a lot of T-shirt sales.
Tracking sharks and
other marine life is essential to understanding their populations, Wetherbee
said.
So much is unknown about life in the oceans. “Our government is committed to protecting fish populations,” Wetherbee said. “Our whole goal is to manage fish populations in a sustainable way and information gathering is all important.”
So much is unknown about life in the oceans. “Our government is committed to protecting fish populations,” Wetherbee said. “Our whole goal is to manage fish populations in a sustainable way and information gathering is all important.”