A pregnant porbeagle shark met a tragic end in the waters of Bermuda, a victim of shark-on-shark predation. This horrifying incident came to light thanks to the data collected by a satellite tag attached to the unfortunate porbeagle. Marine biologist Brooke Anderson of Arizona State University was shocked when she analyzed the temperature data from the tag, which pointed towards only one conclusion – the pregnant female porbeagle had been devoured by a larger shark.
Porbeagles, also known as Lamna nasus, are large mackerel sharks found worldwide. These magnificent creatures face a decline in numbers due to recreational and commercial fishing activities. They can grow up to 3.7 meters long, weigh up to 230 kilograms, and live for several decades. Female porbeagles have a slow reproductive cycle, giving birth to live pups after a gestation period of eight to nine months. With a delayed reproductive maturity age of around 13 years and a low litter size, porbeagles are highly susceptible to population declines.
To better understand and protect porbeagles, Anderson and her team used satellite tags to track the sharks’ movements. The tags, known as pop-off tags, record valuable data such as temperature, depth, and location before detaching from the shark and transmitting the stored information to scientists. The tags provided crucial insights into the behavior of the pregnant porbeagle in the days leading up to her untimely demise.
On March 24, the satellite tag recorded abnormal data as the porbeagle’s body temperature rose significantly while maintaining similar diving patterns. The sudden temperature increase indicated a predator attack, likely by a white shark or shortfin mako. The tag’s journey through the predator’s digestive tract before surfacing highlighted the harsh reality of shark predation in the open ocean.
The shocking discovery of shark-on-shark predation, especially involving a pregnant porbeagle, raises concerns about the species’ survival. Multiple sharks, including the unborn pups, were lost in a single predatory attack, underscoring the impact of such encounters on porbeagle populations. Anderson emphasizes the need for further research and tagging efforts to unravel the mysteries of shark behavior in the open ocean.
The incident in Bermuda sheds light on the complex interactions among large sharks and underscores the importance of conservation efforts to protect vulnerable species. With advancements in satellite tagging technologies, scientists can now uncover previously unknown behaviors in marine animals, paving the way for a deeper understanding of the challenges faced by sharks in their natural habitats. Tagging initiatives hold the key to unraveling the enigmatic world of open ocean predators and their role in shaping marine ecosystems.