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Kathy and Deb with dead torpedo ray in sled.
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On January 26th, a large female torpedo ray stranded dead on the shores of Corporation Beach in Dennis, MA, and was reported to the NECWA hotline (508-566-0009). This would become torpedo ray stranding #53 for the 2022 season which extends into the early months of 2023.
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| Torpedo ray stranded dead at Corporation Beach. |
NECWA volunteer, Deb Capobianco responded immediately and rushed down to the beach to secure the carcass as the animal stranded below the high tide. The carcass would have washed away if not for her fast action. Being a large carcass, Deb was concerned that she would not be able to drag the carcass on her own. So Deb was able to maneuver the carcass onto a sled and dragged the carcass above the high tide live with a lot of effort. Thank you Deb!
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| Female torpedo ray in Deb's sled. Ready for transport. |
Soon, NECWA volunteer, Kathy Miller, joined her and the two ladies necropsied the carcass on-site. These external and internal examinations are crucial for our better understanding of this little know species that lives off the Cape year round. The first step when documenting any stranding is to collect positional information which Deb quickly did. Then the team continued with the external examination through the collection of photographs and body measurements.
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GPS position of the stranded dead torpedo ray.
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Next, Kathy opened up the carcass to confirm the sex and to examine internal tissues, including a thorough examination of the digestive tract to help determine what this species eats when in our coastal waters. Although Kathy had seen this many times before, she was amazed at the size and color of the eggs in each of the large 2 ovaries. Each ovary sits on top of one of the two kidneys, which are also very large and heavy in size. The eggs in this female were well-developed and quite large, with huge amounts of green yolk. No one knows why torpedo ray eggs have green yolks and NECWA has reached out to many fishery scientists for help on this issue. Unfortunately, no one has yet figured out the answer, and this is a reminder as to why this type of research is so important, especially when dealing with little known species lie the torpedo ray, the only electric ray in our waters.
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| A photo of the ovary with its large eggs that have green yolks. |
As they wrapped up the necropsy, Kathy collected samples of muscle and liver for further study. NECWA is collaborating with Dr. John Logan (Div. of Marine Fisheries) and John Chisholm (Anderson Cabot Center for Ocean Life) so tissues and data will be shared with these scientists. The team was also able to weigh the carcass with the assistance of a dog walker who help was gratefully accepted as this carcass weighed over 118 lbs. On average, female torpedo rays are larger and heavier than males and the largest female that NECWA has weighed came in around 200 lbs.
At the end of each necropsy, we cut out the liver and chop it up into bit sized pieces in order to feed the hungry gulls that flock to each of our necropsies and watch us with great aniticipation. This is one small way we can give back to the other wildlife that depend on these types of stranding for their survival. Kathy pulled the carcass back into the water in the hopes that it would drift offshore so as not to land again on a beach and decompose in front of anyone's beachfront property.
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| Gulls enjoying the liver from the female torpedo ray. |
The last step of any torpedo ray necropsy is to cut a deep V-notch into their lobed caudal fin (tail). This cut makes it easy to see that we have necropsied the carcass, eliminating the need to mark the carcass with any type of plastic or metal tag. We were hoping that this would be the last torpedo ray stranding for the season, but a few days later, on 1/28/2023, the 54th torpedo rays carcass was reported to NECWA and was necropsied by NECWA intern Kevin Dougherty and NECWA volunteer Al Poirier. Go Team!
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Normal torpedo ray tail on the left and cut tail on the right.
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If you see a live or dead torpedo ray stranded on a beach, please call the NECWA hotline at 508-566-0009.
To report your sighting to NECWA online, click
HERE to go to our online Jotform.
Thank you!
To learn more about torpedo rays, click HERE to go to the Delaware government site.
To watch a video of a torpedo ray under the water, click HERE, to go to Blue World.
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