It is very well undisputed that whale sharks are huge. With an average adult length of eight or nine meters (about 28 feet), they are shopper than some of your favorite marine life forms. But for almost a decade, the battle of the sexes persisted: who is older, man or woman?
According to a new study, published in Frontiers in Marine Science on Wednesday, a decade-long analysis has confirmed female sharks to rule as the largest fish in the sea – males up to an average of 14 meters (about 46 feet) Pushed to reach.
Mark Maken, a fish biologist at the Australian Institute of Marine Science and the first author on the paper, said some whales have also grown up to 18 meters (59 ft) long.
“It’s absolutely huge – about the size of a bandy bus on a city street,” he said. “But even though they are large, they are growing very slowly. It is only 20 cm or 30 cm per year.”
Due to slow growth rates, the team tracked 54 individual whale sharks over 10 years, recording more than 1,000 measurements with stereo-video cameras.
“It’s basically two cameras set up on a frame that you push underwater,” said Brett Taylor, a scientist at the Australian Institute of Marine Science and co-author of the study.
“It works the same way our eyes do – so you can calibrate two video recordings and get very accurate measurements of sharks,” Taylor said.
The team also learned that the increased size of the female whale shark could benefit when it comes to producing offspring. Only one pregnant whale shark has been documented, but unlike most sharks carrying between two and 12 young, whale sharks have up to 300.
This discovery may also have implications for conservation efforts. The whale shark has been listed as an endangered species since 2016. Given their long growth rates, whale sharks can be targeted by fishermen, resulting in further declines in the population for animals.
“If you are a very slow-moving animal and it takes you 30 years or more to mature, the chances of disaster are very high before you have a chance to breed,” Meeken said.
“And this is a real concern for whale sharks.”