On the morning of March 19th, we were notified of a dead dolphin on the beach on Kiawah Island. Nicole and Colin Perkins-Taylor (CSS/NOAA) met Kiawah Beach Patrol and LMMN Dolphin Education volunteer, Karen Thompson, on the beach to retrieve the animal. This was a big dolphin and likely weighed several hundred pounds - getting it into our truck was no easy task.
The dolphin was brought back to the necropsy lab at Hollings Marine Laboratory for a full examination. It was a male bottlenose dolphin that was over 8 ft in length. It was in fair body condition and had numerous healed abrasions along the right side of its body. Teeth were worn down to the gum line, suggesting an advanced age. Dorsal fin photos were provided to the National Marine Mammal Foundation, who confirmed it was a known Charleston animal first seen in the 1990s (likely 30+ years old!). Sadly, this dolphin was also identified by Lauren as a known strand feeder.
Our external exam noted swelling and pus-filled lesions along the left jaw, with an apparent old injury under the left eye. The internal exam found necrotic blubber along the lower left jaw and lymphadenitis, suggesting a severe localized infection. Other skin lesions were also present across the body.
Upon further examination of the internal organs, a 7 cm stingray barb was found piercing the top of the right lung. The barb was removed and photographed. It is not possible to positively identify the species of ray, but it was possibly from an adult Southern stingray (Hypanus americanus) or Roughtail stingray (Dasyatis centroura).
It is probable that the dolphin was first pierced by the barb under the left eye, which led to infection, before it slowly migrated and eventually pierced the right lung. Stingray barbs are not an uncommon find in stranded dolphins, especially within the Southeast as they both
utilize shallow coastal and estuarine habitats. Histopathology results showed that death was likely attributed to a combination of chronic respiratory disease compounded by the
bacterial infection involving the cheek and associated lymph node that likely went
systemic.
This was an interesting case for the team, but a sad loss to our local population. Thank you to everyone who helped transport the animal and to Lauren, Anna Diel, Tony Laccetti, and Bonnie Ertel for help during the necropsy. Thank you to the National Marine Mammal Foundation for providing sighting information for this animal.
Check out the link below for an interesting poster about stingray barbs found in Sarasota Bay Dolphins:
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