Karen Provazza | Director of Marketing
On Monday, September 12, 2016, our Marine Mammal Rescue Manager Ashley Stokes received an unusual report: a swordfish washed up on Cable Beach in Rye. While not a marine mammal, our Rescue Team was eager to assess the situation and equipped to remove the carcass from the beach.
The caller indicated that they thought the 8-foot fish was alive when it washed ashore, but when our crew arrived, it was deceased. Plans were quickly made to bring the swordfish back to the Center so Aquarist Rob Royer could perform a necropsy to try to determine cause of death. The hands-on examination of the fish provided an amazing educational opportunity for our staff and visitors.
“It is rare for a swordfish to be close to shore,” said Royer. “Typically they are at least 100 miles off shore. They are deep water fish and in my 12 years at the Center, I have never seen one wash up.”
Rob performed the necropsy on Tuesday morning. “There were no external signs of injury, disease, or human interaction (no line, hook, or net marks), so we really wanted to take a look inside to see if there were any obvious signs of cause of death.”
While no internal injuries were found, there was a copious amount of a thick yellow mucus in its stomach and around its organs, as well as parasites. It’s stomach was void of anything but a small amount of seaweed. It is likely that the massive fish died as a result of an internal infection. The wave and wind activity during the past week likely helped drive the weakened animal closer to shore, ultimately washing it ashore.
Swordfish are characterized by a long, flat bill, which is used to slash at and injure its prey. They are found widely in tropical and temperate parts of the Atlantic, Pacific, and Indian Oceans. They are a highly migratory species and typically move towards colder regions, like the Gulf of Maine, to feed during the summer. Swordfish feed most often at night, when they rise to near-surface waters in search of smaller fish. Adult swordfish have few natural predators and grow to 14.9 feet and 1,430 pounds. They are popular, yet elusive, sport fish.
The Center plans on preserving the skeleton for educational purposes. Most of the soft tissue was removed from the skeleton and the remains are currently buried with compost to assist in the decay of the remaining tissue. The Center plans on having the bones ready for use next spring.