Great white sharks are afraid of orcas, study finds
S E E D E D C O N T E N T
It appears one of the most fear-inducing predators in the ocean may have a fear of its own.
A new study led by the Monterey Bay Aquarium and published Tuesday in Nature found great white sharks leave their “preferred hunting ground” when orcas — also known as killer whales — enter it. In fact, researchers found the sharks won’t return to those areas for roughly a year — even if the orcas don’t stay that long.
To come to this conclusion, researchers “documented four encounters between the top predators at Southeast Farallon Island in the Greater Farallones National Marine Sanctuary off San Francisco, California,” per the Monterey Bay Aquarium's news release on the findings . The scientists then “analyzed the interactions using data from 165 white sharks tagged between 2006 and 2013, and compiled 27 years of seal, orca and shark surveys at the Farallones.”
More specifically, researchers determined when both sharks and orcas were present at the Farallon Islands by comparing data from the electronic shark tags with “field observations of orca sightings.” This made it possible to demonstrate the outcome on the rare instances when the predators encountered each other,” per the study.
The “robust data sources” helped scientists to “conclusively show how white sharks clear out of the area when the orcas show up,” Jim Tietz, a study co-author, said in an online statement.
The sharks fled the island when the orcas arrived — and did not return until the following season — in all of the cases studied. Data from the electronic tags even showed all the great white sharks left the area just minutes after orcas arrived. This was true even when the killer whales were present for less than an hour.
"On average we document around 40 elephant seal predation events by white sharks at Southeast Farallon Island each season," Monterey Bay Aquarium scientist Scot Anderson said in a statement. "After orcas show up, we don't see a single shark and there are no more kills." "These are huge white sharks. Some are over 18 feet long and they usually rule the roost here," Anderson continued.
It's unclear why exactly the sharks leave. Researchers suspect it could be because the sharks are prey for the orcas, or possibly because they are bullied over food and ultimately forced out.
Sharks hightailing out of the area had an indirect benefit for elephant seals — which are often the preferred meal of both sharks and killer whales — in the Farallones. Researchers found there were “four to seven times fewer predation events on elephant seals in the years white sharks left,” per the study.
"We don't typically think about how fear and risk aversion might play a role in shaping where large predators hunt and how that influences ocean ecosystems,” added Salvador Jorgensen, the study’s lead author. “It turns out these risk effects are very strong even for large predators like white sharks — strong enough to redirect their hunting activity to less preferred but safer areas."
Jorgensen explained the study is important because it is one of the few that "demonstrates how food chains are not always linear," especially in the ocean. Interactions between predators are more difficult to document and analyze due to their infrequency
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I pretty sure most of us have assumed this for awhile, but it's nice to see research confirming it.
Great Whites while impressive predators simply can't compete against orca's. Although not mentioned in the article the solitary shark can't stand up again the pack strategy of orca's (imo)
Basically all sharks fear the Orca because they are so much bigger and smarter.
Lol or is this simply another example of whites fearing blacks?
Orcas also hunt in packs- great whites are solitary hunters. 1 great white vs a pack of Orcas- is not a contest.
Exactly
Like a single bull elephant against a determined pride of lions.
Some things are just predetermined.
Having witnessed Orca's off the Farallones and in the PNW they are very impressive in size and of course hunt in schools.
The Great White is usually a solitary hunter and even though they can reach 18 feet they are not a match for an Orca that can weight up to 18,000 lbs.
I've seen Great Whites in Australia and off the coast of Santa Catalina Island in Southern California. Impressive none the less.
yep, the only time I've seen a single Orca was on a totem pole or other similar piece of art.
they are families, they are never alone.
Back in the middle 70's when I was in the Navy stationed Whidbey Island, WA, I was fishing in 14 aluminum boat off a seaplane ramp. I had fust sized off when I felt the boat move ever so slightly. I turned my head ever so slightly to one side and saw this huge black head sticking out of the water eyeballing me from about 3 or 4 feet away. After about 20 seconds or so the head just silently slid back down into water. I just laid there unmoving and just praying it would not surface again underneath the boat. My fishing partner, who was sound asleep at the other end of the boat missed all of it. I still get a chill down my spine to this day when I think about it...
We were in the middle of a pod of Orco's off the coast of B.C. It wasn't a 14 ft aluminum but it was 22 ft Boston Whaler....Scared the crap out of us...We didn't know whether to fire up both engines and try to run out of the pod or just stay put and bounce along with them...We bounced along with them for around 45 minutes...The longest 45 minutes in my lifetime.
I can imagine looking one in the eye from 3 to 4 feet would be exciting or terrifying to say the least. It probably thought that you were to small even for a snack...LOLOL
To top that off, when I was at McMurdo Station, Antarctica in the late 80's I had been there about three days and had just bought a Cannon 35 mm T50 SLR camera and was looking for things to take pictures of. I asked somebody I saw if there was any wildlife around. This one gal said, "We just saw some penguins down by the ice edge.". I said thanks and proceeded to a area called Hup Point and sure enough there were some Adele penguins on the shore. There was about 3 feet of open water between the shore and the ice. Did not think anything of it and took some shots. I looked further out on the ice and there was a solitary Leopard seal sitting by a hole in the ice. That explained why the penguins would not go in the water. I took some shots if the seal and looked further out and there was a large circular hole in the ice about 25 feet across. All of a sudden two large black finds cut the surface of the water. I took some shots of the Orcas and it all became clear. Penguins would not go into the water on account of the seal, who would not go into the water on account of the Orcas! Leopard Seals eat penguins and Orcas eat Leopard Seals...
That's amazing, the food chain in real life and you got photos....
Hey I was thinking about your encounter with the Orca in your 14 ft boat. I'll bet that the Orca, in some way, recognized you as being Navy (were you singing Anchors Away) and of course he's navy so not eating you was professional courtesy.
You guys sure stick together....
You betcha!
It's good to remember that sharks kill a lot more people than Orca's do....
Killer Whales are the coolest animal on the planet....to me anyway !
I have seen footage of great whites being eaten by orcas.
I always think of orcas as dolphins that are working out and on steroids.