Researchers have been tracking a 26-foot/7.92-meter endangered whale shark – named “Rio Lady” – with a satellite transmitter for more than four years – a record for whale sharks and one of the longest tracking endeavors for any species of shark.
Whale sharks need to travel about 5,000 miles/8,047km per year to find enough food to survive. Whale shark populations worldwide have declined, primarily as a result of interactions with humans, to the point where they are now listed on the International Union for Conservation of Nature’s “Red List” as “Globally Endangered.”
Researchers at at the University of Rhode Island and Nova Southeastern University in Florida tracked Rio Lady for about 27,000 miles/43,252km over nearly 1,700 days between 2018 and 2023. Her journey took her through the Gulf of Mexico, the Caribbean Sea and out into the Atlantic Ocean south of Bermuda.
A study conducted by the researchers was published in the journal Marine and Freshwater Research, describing Rio Lady’s movement, migration and habitat use.
Llead author Daniel Daye, who graduated from URI in May 2023 with a master’s degree in biological and environmental sciences, said:
“This was an amazing length of time to be able to track the movements of a wild animal. Four years of data about the movements of even a single individual has allowed us to investigate whale sharks to an unprecedented degree and investigate questions that can’t be answered with shorter tracks.”
Rio Lady was tracked by satellite telemetry using a smart-position and temperature transmitter (SPOT) affixed to her dorsal fin. The tag provided location transmissions over four years of her life.
Satellite telemetry has revolutionized the study of animal movement – particularly with marine species – allowing researchers to uncover long-term movement patterns and core areas for marine animals, the study says.
Brad Wetherbee, assistant professor of biological sciences at URI and an expert on shark movement and migration who consulted on the project, said:
“As the biggest fish in the ocean, it is challenging to follow the movements of whale sharks over long periods of time. But information on the movements of these endangered sharks is important for management of their populations.”
You can follow Rio Lady’s journey on the Guy Harvey Research Institute tracking website. Click on “Project 21” and then select “Rio Lady” on the right.
