New Delhi | Jagran Trending Desk: Offering a deeper insight into the biology of Earth’s largest fish -- the whale sharks -- research has found that both male and female whale sharks grow at different rates with the females growing slightly slower but getting bigger in size than the male whale sharks.

According to a report by Reuters, quoting the researchers who have conducted the study, as saying that they had tracked the growth of 54 whale sharks -- both male and female -- for a period of 10 years at the Ningaloo Reef off Australia’s west coast, where hundreds of these sharks migrate annually.  

According to the study, both male and female sharks were found to have their fastest growth as juveniles. They grow 8-12 inches annually, the study stated.  

Overall, males were found to grow slightly more quickly than females, plateauing at around 26 feet (8 meters) long after reaching sexual maturity at about 30 years old. Females plateaued at around 14 meters (46 feet) when they reached sexual maturity at about age 50.

According to the report, it is believed that whale sharks of both sexes may live for about 100-150 years and the longest shark ever lived on this planet reached about 60 feet.

“Whale sharks are remarkable in that, females have massive litters of pups, up to 300 at one time. Being very large is almost certainly a prerequisite for carrying this many young inside a female’s body,” said Australian Institute of Marine Science marine biologist Mark Meekan, who led the research published the journal Frontiers in Marine Science.

These sharks have a brownish-greyish colour on the back and sides with white spots, with a white underside.

“Our study provides the first evidence that male and female whale sharks grow at different rates,” Meekan said, adding that “Previously, researchers had to rely on estimates of growth and age extracted from the vertebrae of dead sharks that had either stranded onshore or been killed by a fishery. Samples were very limited and didn’t cover a very wide size range of animals, confounding attempts to produce reliable estimates of growth patterns.”

These sharks are filter feeders and can swim great distances through the world’s tropical oceans to find their food.

“If it takes many years, 30 or more, for these animals to become mature, there are lots of threats such as hunting and ship-strike that they may succumb to before they get a chance to breed, making conservation strategies for these animals an urgent task,” Meekan further said. 

Posted By: Talib Khan