Page 28 - aruba today

A28 SCIENCE
Tuesday 10 OcTOber 2017

Study: Great white sharks are swimming farther and deeper

By PHILIP MARCELO atively shallower waters of seen what impact contin-
Associated Press the continental shelf where ued growth of white shark
BOSTON (AP) — The move- food sources abound, while populations in the Atlan-
ments of great white sharks adults are more apt to ven- tic has on these habits, or
in the Pacific and Indian ture into open ocean, ob- whether climate change is
oceans have long been serves Christopher Lowe, a playing a role.
the subject of academic shark researcher at Califor- Another key question is
study, but new research is nia State University in Long finding out what these
just starting to shed light on Beach also not involved sharks are actually doing
the behavior of their Atlan- with the research. so far offshore.Researchers
tic Ocean counterparts. Indeed, most of the tagged in northern California sug-
Researchers in Massachu- sharks in the Atlantic study gest offshore movements
setts say white sharks ap- generally followed a north- are for mating, a ritual that
pear to venture offshore south migration along the has never been observed
farther, with more frequen- Eastern Seaboard. among white sharks. But
cy and at greater depths They headed to New- Skomal and his team be-
than previously known in In this Sept. 13, 2012 file photo, Captain Brett McBride places his foundland and New Eng- lieve the animals are more
the Atlantic. hand on the snout of the crew’s first specimen while scientists land waters in the summer, likely foraging — it’s just not
Some of the 32 sharks collect blood, tissue samples and attach tracking devices on then down south to the immediately obvious what
the research vessel Ocearch off the coast of Chatham, Mass.
tracked between 2009 Associated Press Carolinas and even the Ba- they’re feeding on.
and 2014 ended up as far hamas for the winter. “That’s the great mystery
east as the Azores, the Por- is more coastally-oriented, The research is exciting be- Lowe says it remains to be right now,” he said.q
tuguese island chain locat- moving north-to-south and cause it represents the “first
ed more than 2,300 miles remaining on the continen- real insights into the move-
(3,701 kilometers) from tal shelf,” explained Greg- ment patterns of white
Cape Cod, where most of ory Skomal, the study’s sharks” in the northern part
the animals were initially lead author. “So what of the Atlantic, says Tobey
outfitted with satellite tags. we’re now describing is this Curtis, a Massachusetts-
They also were found to other component, this off- based shark researcher for
make frequent deep dives shore movement into open the National Marine Fisher-
— as far down as 3,700 ocean.” ies Service who was not in-
feet (1,127 meters) — and Skomal says the work has volved with the study.
spend more time at those implications for shark con- “Prior to this, we were only
dark depths than previous servation efforts since it able to piece together
studies in the Atlantic sug- extends the known habitat information about their
gest. for these ancient preda- distribution from widely
The team, which included tors. White sharks are not scattered reports from fish-
scientists from the state considered endangered or ermen, scientists and the
Division of Marine Fisher- threatened, but it’s illegal public,” he said. “Having
ies, the Massachusetts In- to hunt them in U.S. waters. tracks of individual sharks
stitute of Technology and “You’ve got U.S. protection really helps fill in the gaps,
the Woods Hole Oceano- within 200 miles of shore, and provides a more com-
graphic Institution, had but you have sharks clearly plete picture of white shark
its findings published last leaving that protection that movements and migra-
week in Marine Ecology are vulnerable to harvest,” tions.”
Progress Series, a promi- Skomal said. “We need to The study seems to hew
nent scientific journal. engage other countries closely to what’s been ob-
“Everything we knew pre- fishing in these waters to served of white sharks in
viously indicated that the talk about putting similar other oceans — that juve-
white shark in the Atlantic protections in place.” niles tend to stay in the rel-