Scientists followed the movements of a female whale shark for nearly two-and-a-half years as she swam more than 20,000 kilometres from the coast of Central America to the Marianas Trench near Asia.
The shark was tagged with a transmitting tag back in 2011 in the Pacific Ocean near Panama’s Coiba Island. For the next 841 days, the whale shark, affectionately named “Anne”, was tracked moving south to the Galápagos Islands and across the Pacific to the Marianas Trench, south of Japan and east of the Philippines. This totalled to a distance of 20,142 kilometres.
Whale sharks dive to more than 1,900 metres. But it is unknown what the animal was doing in this area. “We have very little information about why whale sharks migrate,” Héctor M. Guzmán, marine biologist from the Smithsonian Tropical Research Institute
(STRI) and the study’s lead author said in a statement. “Are they searching for food, seeking breeding opportunities or driven by some other impulse?”
While whale sharks have been tracked for shorter distances along similar routes, this report is the longest-recorded migration to date and the first evidence of a potential trans-Pacific route.