The solely whale shark to have been tagged with a monitoring machine on two separate events by researchers has travelled greater than 9,700 miles in simply over 600 days.
Scientists from Nova Southeastern University’s Guy Harvey Research Institute (GHRI) and Mexican conservation non-profit Ch’ooj Ajauil AC tagged the mature, 26 ft lengthy whale shark, dubbed “Rio Lady,” in August, 2018 within the waters off Cancún, Mexico, and have now been following her actions for 20 months.
This is the longest time frame that scientists have tracked a member of this globally endangered species utilizing high-resolution positioning knowledge, the researchers stated.
From August 2018 to the newest “ping” from her satellite tv for pc tag, Rio Lady has lined huge distances, spending lengthy durations of time within the Caribbean, the Gulf of Mexico and even making a brief journey to the waters off the coast of Apalachicola within the Florida Panhandle.
“As of May 12, 2020, Rio Lady has travelled 620 days and at least 9,689 miles in that time,” Mahmood Shivji, Director of the Guy Harvey Research Institute & Save Our Seas Shark Research Center at Nova Southeastern University, instructed Newsweek.
“Her actual distance travelled is even longer; we can only estimate distance travelled based on connecting the detection dots with a straight line, but in the ocean she has not traveled in a straight line between detections.”
“Tracking data are demonstrating that long distance travels of a few thousand miles per year by whale sharks are not unusual,” he stated. “Rio Lady’s travel distance is the longest of the 10 whale sharks we have tracked/are tracking, but we have also tracked her for a longer period than any other whale shark—so far.”
In August, 2007, a crew from Mote Marine Laboratory in Florida and Ch’ooj Ajauil AC’s Executive Director Rafael de la Parra tagged Rio Lady for the primary time close to Isla Mujeres within the waters off Cancún—an space the place whale sharks collect yearly to feed. While analysis has proven that whale sharks are likely to journey alone they often mixture in giant numbers for feeding functions.
The crew fitted her with a “pop-up” satellite tv for pc tag, which indifferent itself from the animal 5 months later, round 5,000 miles away within the southern Atlantic Ocean close to the Saint Peter and Saint Paul Archipelago—situated between Brazil and West Africa.
At the time, scientists suspected that the shark was pregnant as a consequence of her giant girth, and thus, this journey out into the open ocean—away from near-shore feeding grounds—supplied researchers with an vital clue as to the place females of this species give beginning.
Then, in 2018, de la Parra, in collaboration with a GHRI crew, tagged her once more in nearly precisely the identical location. This time although, the researchers fitted her with the next decision Smart Position and Temperature (SPOT) satellite tv for pc tag that was hooked up to her dorsal fin, situated on her again.
“This is the only known case of the same whale shark being satellite tag tracked twice, each at different times,” Shivji stated.
The SPOT tag supplied researchers with extra correct knowledge concerning her place and actions than the “pop-up” tag. Tracking whale sharks over lengthy durations utilizing this sort of knowledge can yield vital data, the scientists stated.
“The strikingly different travel patterns of Rio Lady over the past 20 months compared to her five-month journey into the Atlantic when she was first tracked in 2007-2008, suggests that whale shark individuals may not repeat the same migration pathway annually like many other wildlife species do,” Shivji stated.
“The migration path by individual whale sharks may be different every year but they clearly travel really long distances which is energetically very costly, so the question is what is driving these annually different migration patterns?
“The solely method we’ll discover out is by monitoring many people over a protracted time frame, not less than two or extra years. Rio Lady has been tracked for the longest time interval of any whale shark within the Atlantic Ocean. It will likely be fascinating to see if she is going to head again later this summer season to the feeding aggregation website the place she was tagged in 2007 and 2018,” he said.
It’s also clear that whale sharks spend a lot of time at the surface otherwise the scientists would no be receiving so many “pings” from the fin-mounted SPOT satellite tags, Shivji said. Furthermore, the tracking data could have implications for conservation efforts. The species is classified as “Endangered” on the International Union for Conservation of Nature’s Red List of Threatened Species.
“We’re following 4 different whale sharks which were tracked for eight-to-nine months thus far; hopefully we can observe them so long as we now have Rio Lady so we are able to get a very good understanding of the journey habits of those endangered species and decide how a lot their journey paths intersect with busy delivery lanes the place there’s a threat of collision inflicting shark harm and mortality,” Shivji said.
“The lengthy distance travels of those sharks are additionally taking them by the jurisdictional waters (Exclusive Economic Zones) of a number of nations, underscoring that conservation efforts for whale sharks would require worldwide cooperation.”
Whale sharks (Rhincodon typus) are each the biggest fish and largest sharks within the oceans, rising to round 30 ft in size on common, and weighing as a lot as 20 tons. Despite their giant dimension, these animals—which aren’t whales—are innocent, feeding totally on tiny plankton and fish eggs that they eat whereas swimming together with their big mouths broad open. In reality, the animals are one in every of solely three species of filter-feeding shark, based on non-profit conservation group Oceana.
Unlike different giant sharks, whale sharks—which have a life expectancy of between 70 and 100 years—are thought to offer beginning to lots of of very small infants, nevertheless, this course of has by no means been instantly noticed. The animals are present in tropical oceans everywhere in the world, typically travelling giant distances to considerable meals sources, corresponding to plankton blooms or a mass spawning of fish.
Whale sharks are underneath menace from looking—the animals are harvested for his or her fins, oils, meat and different physique components—in addition to ship strikes that happen throughout their lengthy migrations.