Shark Threesome Filmed by Marine Biologists for Science

Key Highlights

• Study Overview: Researchers filmed a unique mating behavior of leopard sharks in the wild, which is rare and insightful.
• Significance: The video offers important data on the reproductive strategies of the endangered Indo-Pacific Leopard shark.
• Conservation Impact: Findings emphasize the necessity of protecting mating habitats for effective species management.
• Research Benefits: The footage may aid in artificial insemination efforts for rewilding leopard sharks.

Springer Nature’s Journal of Ethology has just published a study on a threesome. Yes, that kind of threesome—and it’s being hailed as a win for marine conservation efforts.

That’s because the lovers in this particular trio are leopard sharks. Hugo Lassauce, a marine biologist from the University of the Sunshine Coast, filmed two males and one female of the endangered species mating in the wild in a first-of-its-kind video, shedding light on their natural reproductive behaviors.

“The Indo-Pacific Leopard shark (Stegostoma tigrinum), listed as endangered by the IUCN, has primarily been studied in captivity, with little information on its natural mating behaviors,” the researchers wrote in the study. “Here, we present the first documented observations of group copulation in free-living S. tigrinum, recorded at Abore Reef, New Caledonia.”

A sharky threesome

Leopard sharks, sometimes referred to as zebra sharks, live in coastal waters throughout the Indo-West Pacific region. As soon as Lassauce captured the video and swam back to his team’s boat, they all cheered. It’s difficult to witness sharks copulating in the wild in the first place, so you can only imagine how rare it is to spot endangered shark species mating and get the chance to film it.

“While I was surveying this particular aggregation of leopard sharks, I spotted a female with two males grasping her pectoral fins on the sand below me,” Lassauce said in a university statement. “I told my colleague to take the boat away to avoid disturbance and I started waiting on the surface, looking down at the sharks almost motionless on the sea floor. I waited an hour, freezing in the water, but finally they started swimming up.”

The male sharks then each mated with the female, one taking 63 seconds, the other 47. Talk about a quickie. The female then “swam away actively,” and the males, now lethargic, lay still on the seafloor. Besides the excitement of catching something rare on camera, the video carries significant implications for our understanding of the endangered species.

“These findings provide novel insights into the species’ reproductive strategies and highlight the importance of identifying and protecting key mating habitats,” Lassauce and his colleagues wrote in the study. “Given the conservation concerns surrounding S. tigrinum, understanding these mating mechanisms and recognizing reproductive sites are crucial for effective species management.”

Sharing is caring

Christine Dudgeon, a co-author of the study and a marine ecologist also from the University of the Sunshine Coast, explained in the statement that the video could also support artificial insemination research working to rewild leopard sharks.

“It’s surprising and fascinating that two males were involved sequentially on this occasion,” she added.

It would seem like leopard shark males are more willing to share their lovers than other species.