Unveiling the Intimate World of Sharks: Love, Pain, and Healing in the Deep Blue

The research aligns with previous studies concerning the concealed reproductive behaviors of sand tiger sharks off the coast of North Carolina, which – by analyzing the severe bite wounds sustained by both mating individuals – has gone some way to confirm that while romantic love can be painful, all injuries do eventually mend.

Featured in the journal Environmental Biology of Fishes in early December 2024, an additional study draws us into areas not suited for the faint-hearted, depicting the somewhat aggressive nature of shark mating; a process that necessitates them to press their bodies together during the act. For larger species, this can be a challenging task that typically involves the male biting the female, often resulting in bloody lacerations on her.

The new research indicates that many males also emerge with injuries. Some females retaliate.

In this study, lead author Jennifer Wyffels, a researcher at Ripley’s Aquariums and the University of Delaware, analyzed the mating wounds found in sand tiger sharks – a critically endangered species that can reach lengths of up to 10 feet.

The investigation firstly observed a group of sand tiger sharks within an aquarium, where mating activities had caused serious injuries to a female. Utilizing this data, the researchers developed a scale to categorize the severity and stages of healing of shark mating wounds, with one representing fresh injuries and four indicating the onset of scarring.

Employing this scale, the team then evaluated roughly 2,876 images of 686 sand tiger sharks captured between 2005 and 2020 along the North Carolina coastline. Their results demonstrated that an increase in stage one wounds was noted in late May, signifying the initiation of an intense mating season in that area. The peak plateaued in July, suggesting that mating behavior had become less aggressive by mid to late summer.

Photos gathered during this seasonal timeframe provided further support, showing that – out of the females that remained in the area at the conclusion of the mating season – exhibited stage three and four injuries. This led researchers to deduce that although mating among sand tiger sharks is notably brutal, these sharks exhibit an “exceptionally rapid healing rate,” where deep wounds close in just 22 days and complete scarring occurs 85 days after the injury.

“By combining observations from aquarium and wild sand tiger shark wound healing, we were able to outline wound stages and establish a timeline for recovery for this species,” Wyffels stated. “This data was utilized to infer the mating season for wild sand tiger sharks.”

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