A “pretty sick” porbeagle shark washed up dead along a Cape Cod beach this week, the fourth reported porbeagle stranding this winter as researchers try to figure out what caused the female shark to fall ill.
Shark scientists responded to Sagamore Beach after they received a report of a stranded shark off the Cape Cod Bay shore on Monday.
Local shark researcher John Chisholm was alerted to the shark from the New England Coastal Wildlife Alliance, which had gotten a call about the shark on its rescue hotline.
“Of course, everybody reports a great white shark, but I had a feeling it’d be a porbeagle because of the time of year,” Chisholm told the Herald on Wednesday. In the past, he has said the cold-water porbeagle sharks should be the state shark of Massachusetts because they stick around the Bay State all year.
“When I got there, the porbeagle was still alive, but it was clearly pretty sick,” added Chisholm, who is with the New England Aquarium and also verifies shark sighting reports through the Atlantic White Shark Conservancy’s Sharktivity app. “It was super, super thin.”
The shark was in deep enough water to swim away if it could have, but it was too far gone. The shark eventually washed up dead at low tide, and a crew responded to collect the carcass.
The porbeagle was then sent to NOAA’s Michelle Passerotti and her team to conduct a necropsy as they try to determine what caused its death.
“We’ve been doing a lot of those lately,” Passerotti said of the recent necropsies, noting the four porbeagle strandings so far this winter, which is “kind of unusual.”
The mature female shark was not pregnant and didn’t appear that she was ready to be pregnant, according to the shark biologist in NOAA’s Apex Predators Program.
“That’s a sign she wasn’t in good condition,” Passerotti said. “You tend to see them pregnant or ready to be pregnant at this time of the year.”
The shark’s liver was really shriveled up and scarred. The liver is where porbeagles store all of their energy.
“For it to be shriveled up, that means she wasn’t getting the nutrition she needed and definitely something was going on,” Passerotti said of the skinny animal.
Parasites were also found internally and externally on the shark. The researchers collected tissue samples to help them figure out what caused the shark to get sick.
While it’s sad that the shark didn’t survive, the carcass will help scientists learn more about the species, they said.
“It’s a very sad situation but really important for researchers to get a fresh carcass and see what might have caused its demise,” said Carol “Krill” Carson, founder and president of the New England Coastal Wildlife Alliance. “The information you can glean from that fresh carcass is better than one that’s decomposed and floating around for weeks at a time.”
NECWA’s rescue hotline numbers can be found at www.necwa.org/strandings.html.
Chisholm also urges those who find a stranded shark to email him at [email protected]