A large, predatory shark swimming off Bermuda has been swallowed by a larger shark — even while swallowing a tracking device attached to it — in what scientists say is the first recorded case of its kind.
porbeagle sharksLemna nasus) can grow to approx 12 feet (3.6 meters) long. These large sharks patrol the North Atlantic Ocean as well as parts of the Southern Hemisphere’s oceans that include the Antarctic. Their muscular and fluid forms and angled spear-like teeth make them formidable predators. But it seems that Prebeagle is not immune to its prey.
In an article published on Tuesday (September 3) in the magazine Frontiers in Marine ScienceResearchers describe the possible predation of a porbeagle shark by one of its larger relatives. “This is the first documented predation of prigple sharks anywhere in the world,” senior study author Brooke Anderson, a marine fisheries biologist with the North Carolina Department of Environmental Quality, said in a statement.
A pregnant female shark was tagged off Cape Cod in October 2020 using a pop-off satellite archive transmitter and tag (PSAT). The data from these devices was used to track the depth and geographical range of the shark over time. While satellite transmitters are permanent, PSAT tags are designed to be removed from the animal after a year, recording data about the animal’s movements.
Related: Great white sharks split into 3 populations 200,000 years ago and never mixed again – except for one hybrid found in the Bermuda Triangle.
Porbeagles follow their prey and change their position in the water column during the day.
Their depth is calculated using pressure and temperature data from PSAT tags. Abnormalities in pressure and temperature indicate that the animal is dead or that the tag was removed prematurely.
In this case, the shark fluctuated between the surface and 328 feet (100 m) until December 2020, when it began diving to a depth of 2,600 feet (800 m) during the day, hovering at about 650 feet (200 m). The night continued this pattern as it moved south, where it stuck to the waters off the coast of Bermuda.
On March 24, 2021, the temperature patterns associated with its recorded depth changed drastically. While the shark previously navigated waters between 43.5 and 74.3 degrees F to – (6.4 to 23.52 degrees C), on that day the tag recorded temperatures between 61.5 and 76.5 degrees F (16.4 to 24.72 degrees C) despite the residual. . in a similar depth range
The researchers believe this shift meant the tag was inside another shark’s stomach at the time, as the temperature was warmer than it would have been at those depths.
Based on the geographic range of sharks large enough to eat a chicken, this predator is likely either white shark (Carcharodon carcharias(or short fin mako)Isurus oxyrhynchus) the authors said. A white shark seems more likely given the tag’s more stable depth range when swallowed – makos tend to dive deeper and then come up quickly.
The team said the finding has implications for porbeagle populations — a species already threatened by historical overfishing. there is Listed as vulnerable By IUCN Anderson said: “The hunting of one of our pregnant chicks was an unexpected discovery. We often think of large sharks as apex predators. “But with technological advances, we are beginning to discover that the interactions of large predators can be even more complex than previously thought.”
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