u PAGE DESIGN BY VICKY TSUNG© Shutterstock.comMore on the research
[Sal] Jorgensen was lead author of the
paper, which was published in the journal
Nature Scientific Reports.Tracking great white sharks
From 2006 to 2013, [Jorgensen] and other scientists
from the aquarium and Stanford University tracked 165
great white sharks with high-tech acoustic tags between
Southeast Farallon Island, Tomales Point in Marin
County and Año Nuevo Island in San Mateo County.
They attached the tiny tracking tags using a 10-foot
pole and a small titanium dart.Safer season
The study found that it was rare for killer whales to swim past
the Farallons between September and December, when white
sharks are there in large numbers every year to hunt seals.
ver since the 1975 movie Jaws, great white
sharks have been considered the most
fearsome predators in the ocean. But new
research published shows that may not be the case.
When great whites hunting for seals near the
Farallon Islands off San Francisco encountered
killer whales, known as orcas, swimming by, they
immediately fled, swimming long distances to get
away and didn’t return until the following year,
according to a study by researchers at the Monterey
Bay Aquarium, Stanford University and Point Blue
Conservation Science.
“After orcas show up, we don’t see a single
shark,” said Scot Anderson, a white shark expert at
the Monterey aquarium.Great white sharks are amazing hunters. They
can grow up to 20 feet long and weigh more than
4,000 pounds. But killer whales are even bigger,
growing up to 30 feet long and weighing 10,000
pounds or more.
White sharks swim 35 miles an hour—faster than
the world’s fastest man, Jamaican sprinter Usain
Bolt, can run. But killer whales swim just as fast, are
stronger and hunt in groups, like wolf packs. And they
have been documented, on occasion, eating white
sharks. Two years ago, five dead white sharks washed
up in South Africa, having been killed by orcas.
“As amazing as it seems when you see a 17-foot
shark swim by the boat, along comes a bigger
predator, the orca,” said Sal Jorgensen, a white
shark expert at the Monterey aquarium. “It’s pretty
humbling to see.”
Although relationships between large predators
on land have been studied for years, little is known
about how large predators in the ocean interact.
Scientists say the white sharks may well be fleeing
out of fear they will be eaten. They might also be
being bullied by the killer whales, who also eat seals
and sea lions.News
The animal great white sharks fear
u by Paul Rogers / © 2019, The Mercury News (San Jose, California).
Distributed by Tribune Content Agency, LLC.05101520Topic Talks252019 SEPTEMBER 19–21
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