Chase, love bites and put in position

Even the biggest fish in the sea have their secrets, but now, scientists have captured rare footage of the courtship behaviors of whale sharks, offering new insights into the elusive sex lives of these giants.

The video was captured in May 2024. Researchers entered the water after being spotted by a spotter plane that spotted a female whale shark in waters 131 feet (40 meters) deep off the Ningaloo Reef. Western Australia. Shortly after sampling that shark, a male whale shark arrived, and the research team took video footage of the two sharks interacting. The team’s research was published this month in Frontiers in Marine Science.

whale sharks (Rhincodon type) are elasmobranchs – the group of cartilaginous fish that includes sharks, rays, skates and sawfish. Whale sharks are also the largest fish in the world, typically about 30 feet (9 m) long. According to the American Museum of Natural History, one of the the biggest whale sharks ever it was nearly 61.67 feet (18.8 m) long. The largest known whale shark egg, found in 1953, was nearly a foot (0.3 m) long.

The animals’ mating behaviors remain quite enigmatic – courtship has only been observed off the Saint Helena Islands and on Ningaloo Reef.

At Ningaloo – the sight of the behavior described recently – male whale sharks outnumber females three to one, based on data collected from more than 1,000 sharks in the area over the past decade.

Sharks off St. Helena have been observed laying down in a belly-to-belly formation, although the recent encounter did not go that far. In the May 2024 event, the team observed that the male shark followed and dived several times at the female.

“The male shark increased its swimming speed and lunged at the female’s caudal fin again, this time making contact and briefly biting the tail,” the team said. “The female responded by quickly pivoting with her pectoral fins pointing towards the male.

But the recent couple was not made in heaven. The female moved away from the male and “descended rapidly into the depths”. The team stated that the behaviors they observed “did not seem to result in a successful mating”, although it is possible that the two sharks mated in deep water. The team concluded that the female they observed was not sexually mature based on its size.

Whale sharks are a endangered species. According to the AMNH, the population of the species may have decreased by 50% in the last 75 years. Whales are hunted illegally for their meat, are caught as bycatch, and their habitats are damaged by oil spills, plastic pollution, and human transportation and tourism.

Recent video shows that despite many threats, the giant fish persists, although perhaps not for this particular couple. Love is in the air – er, water – for whale sharks, and scientists have managed to capture it on camera.