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- Great white sharks will flee the feeding grounds if a killer whale is present.
- They will not return to the food court until next season.
Great white sharks may be one of the most feared creatures in the world's oceans, but so-called "white death" sharks in Australia are terrified by killer whales and will flee the feeding grounds if they are present, according to a report. new study.
Researchers at the Monterey Bay Aquarium in California and partner institutions say not only are the big whites going to flee – and they run away a few minutes after the arrival of an orca – they will not return to the eating places until the next season, according to the study published Tuesday in the journal Nature.
"When they face killer whales, white sharks will leave immediately their favorite hunting ground and will not come back for a year, although orcas are just passing through, "said senior author Salvador Jorgensen, principal investigator at the Monterey Bay Aquarium, in a statement Press.
Scientists used data from 165 white sharks tagged between 2006 and 2013, and compiled 27 years of surveys of seals, killer whales, and sharks in the Grand Farallones National Marine Sanctuary, off San Francisco, California .
They documented four encounters between the Great Whites and Orcas during this period southeast of Farallon Island. In all four encounters, the same scenario ensued: the great whites left him within an hour of the arrival of a killer whale.
The encounters have proven to be a good thing for the elephant seals that inhabit the Farallones. When the big whites were frightened, four to seven less attacks on seals were documented, the researchers said.
"On average, we document about 40 elephant seal predation events by white sharks in southeastern Farallon Island," said Scot Anderson, a scientist at the Monterey Bay Aquarium. "After the killer whales have come out, we do not see a single shark anymore and there are no more victims."
(MORE: Volcanic eruptions have caused 'great death', says new study)
When killer whales are not present, large Whites appear each year in the Farallones between September and December and remain for about a month feasting on seals. Orcas, on the other hand, do not frequent the sanctuary regularly and only appear from time to time.
Interactions between the major predators of the ocean are not well documented. Therefore, these results are important to better understand the large predators and the impacts of these encounters on the larger ecosystem, noted the researchers.
"In general, we do not think that fear and risk aversion can affect the hunting of large predators and its influence on ocean ecosystems," said Jorgensen. "It turns out that these risk effects are very important even for large predators such as white sharks – powerful enough to redirect their hunting activities to less desirable but safer areas."
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