PORTLAND, Ore. (KOIN) – A dead, 12-foot thresher shark washed ashore near Cranberry Beach on the Long Beach Peninsula in Washington last week — and the corpse served as an opportunity for an impromptu dissection, according to the Seaside Aquarium.

The aquarium said they weren’t able to retrieve the female shark, which was found on Wednesday, until Thursday, and by the time staff arrived, someone had cut off the dorsal fin and removed the jaws. 

Experts say this is not illegal, but it does compromise scientific data. 

The shark was too big to freeze, so the aquarium staff decided to dissect it that day. 

“It was a great learning opportunity for staff and people passing by,” the Seaside Aquarium wrote in a Facebook post. “We had a few young kids put on gloves and get their hands dirty!” 

Staff took external and internal measurements, along with tissue and organ samples. These samples will be sent to Taylor Chapple who studies sharks at Oregon State University. 

OSU’s Big Fish Lab has more information online about sharks and other large marine predators. 

The common thresher shark is one of the largest found off the Oregon coast. It grows to about 20 feet long and is identifiable by its long caudal fin, or tail. The tail can be up to 50% of the shark’s body length. Its other features include a short head and cone-shaped nose. 

Thresher sharks are found in tropical and temperate seas throughout the world and feed on squid and schooling fishes. They sometimes use their long tails to stun their prey, but thrashing the water to frighten it. 

They are not generally considered a threat to humans.