The largest fish in the world survive to 130 years
In order to find out how fast whale sharks grow, scientists ten years in a row returned to the same shore of one of the islands of the Maldives archipelago, near which whale sharks gather once a year. Cameron Perry, the head of the study, swam with these harmless giants and measured them with a tape measure and a laser range finder and filmed on camera. In total, Perry collected data on the growth dynamics of 44 sharks, mostly young; scientists recognized individual individuals by the unique pattern of spots on the skin.
Based on the data collected during the dive, scientists have compiled a mathematical model that allows you to determine the age of the shark by its size. According to the model, male whale sharks reach puberty by the age of 25 and survive to 130 years. Previous estimates, which were made mainly based on the size of the vertebrae, gave a scatter of 79 to 174 years. Perry could not estimate the lifespan of females due to lack of data.
Most of all, knowledge of the life expectancy of whale sharks is needed by ecologists and environmentalists; this will help to estimate the population size and its recovery rate. Whale sharks are rare with humans, so there is no exact data on their numbers, but there is reason to believe that this is one of the rarest fish in the ocean. Since 2016, the whale shark has been listed as an endangered species of the International Red Book.
Perry's findings are published in the journal Marine and Freshwater Research.