The Unconventional Travel Companion: Remoras and Their Whale-Riding Adventures
There are many ways to cross an ocean, but few are as stylish or fascinating as the remora’s whale-surfing journey. These unique fish have developed a remarkable relationship with large marine animals, particularly humpback whales, allowing them to travel vast distances across the ocean with ease.
Scientists studying humpbacks off the coast of Australia have captured rare footage that showcases the remoras’ impressive behavior. The video shows groups of these fish peeling away from their host in what appears to be a high-speed game of chicken, just moments before the whale breaches the surface. As the humpback plunges back below the surface, the remoras return to the whale, sticking to it with the precision and timing of Olympic gymnasts. This elegant display is all the more impressive considering that the remoras live upside-down and survive on dead skin flakes.
A Unique Symbiotic Relationship
Remora australis spend their entire lives aboard whales or other large marine mammals, using them as giant cruise ships to travel across the ocean. These fish have an adhesive plate on their head that creates a vacuum seal, allowing them to attach themselves to the whale and hang on for the ride. This symbiotic relationship benefits both parties: the remoras feed on the whale’s dead skin and sea lice, while the whales receive a form of natural cleaning.
On whale cams, clingy fish steal the show. Marine scientist Olaf Meynecke, who recorded the accidental close-ups of the remoras’ high-speed whale surfing, had placed suction-cup cameras on humpbacks during their annual migration from Antarctica to the waters off Australia’s Queensland state. His primary goal was to study whale behavior, but his video feeds were often filled with dozens of photobombing remoras, which rode in groups of up to 50 as they clung to the same spots where his cameras were attached.
“Whenever the whale was breaching and doing particularly fast movements, it appears that the sucker fish were responding very quickly to the movements,” said Meynecke, from the Whales and Climate Research Program at Griffith University. “They knew exactly when to let go of the body of the whale before it was breaching the surface of the water and then returned to the same spot only seconds later.”
Hitchhikers with Good Instincts
Remoras are harmless to the massive humpback whales, which can weigh up to 40 metric tons. However, Meynecke’s footage suggested that the whales might find their hangers-on annoying. He noted that some individuals with high numbers of remoras were continually breaching, possibly trying to get rid of them.
“We’ve had individuals with high numbers of these remoras and they were continually breaching and there were no other whales that they were communicating with,” he said. “It appeared that they’re trying to just get rid of some of these remoras and they were checking whether they had less after they breached.”
The Mystery of the Journey’s End
Australia’s so-called humpback highway is a migratory corridor traversed by 40,000 of these mammals each year. They bring them close to the country’s eastern coastlines for months as they move from icy Antarctic waters to the balmy seas off the coast of Queensland and back. However, the duration of the journey undertaken by the freeloading fish, which only live for about two years, remains a mystery.
“I suspect that the majority would probably leave at some point, maybe in temperate waters, but then where do they go?” Meynecke said. “Do they find other species that they can then use as a host and wait until the humpback whales have come back?”
In the absence of whales, sucker fish avoid predators by seeking out other large creatures to latch onto, including manta rays, dolphins, and even unlucky scuba divers. “”
“Much to the annoyance of the divers, of course,” Meynecke said. “They’re not easy to get rid of.”