A team of scientists has tracked a whale shark (Rhincodon typus) across more than 20,000 kilometers (over 12,000 miles) of ocean, the longest migration ever recorded for the species.
In 2011, the researchers attached a transmitting tag to a shark they named "Anne" in the Pacific Ocean near Panama's Coiba Island. Over the next 841 days, Anne's transmitter would ping the ARGOS satellite whenever she swam near the surface. Those data points allowed the team to follow her movements south to the Galapagos Islands and clear across the Pacific to the Marianas Trench south of Japan and east of the Philippines—a distance of 20,142 kilometers (12,516 miles).
They reported their findings in the journal Marine Biodiversity Records in April.
The discovery solidifies the whale shark's place among the ocean's most widely traveled creatures, alongside leatherback sea turtles, gray whales and Arctic terns. Another whale shark tagged in 1995 held the previous record for the species with a 13,000-kilometer (8,100-mile) swim in 37 months.
But beyond knowing that they're capable of swimming vast distances–females can cover 67 kilometers (42 miles) in a single day—there's still a lot to learn about whale sharks.
"When I first began working on them, their taxonomy was debated, and it still wasn't clear how they reproduced," study co-author and biologist Scott Eckert of Principia College in Illinois said in a statement. "Despite being the world's largest fish, it's amazing to me how little we know about this species."
Part of the reason for those gaps in our knowledge is that whale sharks' movements are difficult to track. In the course of this research, the scientists had to contend with a 235-day period during which they received no transmissions from Anne's tag. She had likely dived too deep—whale sharks can plunge to depths of almost two kilometers, or more than a mile—for the tag to communicate with the satellite.
The team hopes that plotting out the course Anne and other whale sharks take will help to understand what motivates them.
"We have very little information about why whale sharks migrate," Héctor M. Guzmán, a marine biologist at the Smithsonian Tropical Research Institute and the study's lead author, said in the statement. "Are they searching for food, seeking breeding opportunities or driven by some other impulse?"
Evidence has surfaced in previous studies showing that even whale sharks living thousands of kilometers away from each other are still pretty closely related, so reproduction probably has something to do with these long-distance treks.
A more nuanced understanding of their behavior could also help scientists, conservationists and policymakers try to navigate the challenge of protecting such a cosmopolitan animal, especially with all of the threats that whale sharks face. They can ingest plastic as they siphon plankton from the water column, and fishing boats target them for their fins, cartilage and meat.
Even the tourist boats that bring swimmers and divers who want to share the current with a fish that grows as long as 12 meters (40 feet) and weighs up to 19,000 kilograms (21 tons) could be posing problems. Guzmán said researchers have found that the whale sharks around Coiba Island try to stay away from people.
In 2016, the IUCN listed the species as endangered for the first time. And biologists figure that the world's tropical and subtropical seas hold fewer than half the number of whale sharks that they did 75 years ago, increasing the urgency for their protection.
"These studies are critical as we design international policy to protect transboundary species like the whale sharks and other highly migratory marine species," Guzmán said.
Scuba Divers Rescue World's Biggest Fish Trapped in Net https://t.co/8EUL7zTj6x @AnimalPlanet @peta @CenterForBioDiv @MercyForAnimals— EcoWatch (@EcoWatch)1502721748.0
Reposted with permission from our media associate Mongabay.
- 9 Facts That Will Change How You Think About Sharks ›
- NASA Technology Could Help Save the World's Largest Shark - EcoWatch ›
By Robin Scher
Beyond the questions surrounding the availability, effectiveness and safety of a vaccine, the COVID-19 pandemic has led us to question where our food is coming from and whether we will have enough.
- Can Urban Farms Prevent Hunger in 54 Million People in the U.S. ... ›
- New Report Finds Malnutrition World's Top Killer Amid Pandemic ... ›
- Oxfam Warns 12,000 Could Die Per Day From Hunger Due to ... ›
- Three Ways to Support a Healthy Food System During the COVID ... ›
- Trump USDA Resumes Effort to Cut Food Stamp Benefits - EcoWatch ›
- Pandemic Threatens Food Security for Many College Students ... ›
EcoWatch Daily Newsletter
Tearing through the crowded streets of Philadelphia, an electric car and a gas-powered car sought to win a heated race. One that mimicked how cars are actually used. The cars had to stop at stoplights, wait for pedestrians to cross the street, and swerve in and out of the hundreds of horse-drawn buggies. That's right, horse-drawn buggies. Because this race took place in 1908. It wanted to settle once and for all which car was the superior urban vehicle. Although the gas-powered car was more powerful, the electric car was more versatile. As the cars passed over the finish line, the defeat was stunning. The 1908 Studebaker electric car won by 10 minutes. If in 1908, the electric car was clearly the better form of transportation, why don't we drive them now? Today, I'm going to answer that question by diving into the history of electric cars and what I discovered may surprise you.
As bitcoin's fortunes and prominence rise, so do concerns about its environmental impact.
- 15 Top Conservation Issues of 2021 Include Big Threats, Potential ... ›
- How Blockchain Could Boost Clean Energy - EcoWatch ›
By David Drake and Jeffrey York
The Research Brief is a short take about interesting academic work.
The Big Idea
People often point to plunging natural gas prices as the reason U.S. coal-fired power plants have been shutting down at a faster pace in recent years. However, new research shows two other forces had a much larger effect: federal regulation and a well-funded activist campaign that launched in 2011 with the goal of ending coal power.
- Major Milestone: More than 100,000 MW Worth of Coal-Fired Power ... ›
- Coal Will Not Bring Appalachia Back to Life, But Tech and ... ›
- Renewables Beat Coal in the U.S. for the First Time This April ... ›