A recent study sheds light on the peculiar behavior of suckerfish, or remoras, as they hitch rides on larger marine creatures, including manta rays. While these fish typically benefit their hosts by feeding on parasites, new research reveals a potential downside for the rays.
Marine researcher Emily Yeager from the University of Miami discussed the phenomenon known as “cloacal diving,” where remoras enter the cloaca of manta rays. This behavior, previously observed with whale sharks, is now documented with rays, indicating a unique interaction between the two species.
Although researchers have recorded seven instances over 15 years, they believe this behavior is more common than reported. Yeager suggests that fear might drive the remoras to seek refuge within the rays, as seen in a video where a startled remora swiftly dives into a manta ray’s cloaca.
Professor Brooke Flammang, an expert on remoras, speculates that the fish may engage in coprophagy, or eating feces, during these interactions. She notes that remoras are not typically skittish around humans but may display territorial behavior when competing for resources.
The impact of cloacal diving on manta rays remains uncertain, with concerns raised about potential skin damage and reproductive implications. Yeager emphasizes that this behavior challenges traditional categorizations of symbiotic and commensal relationships between species, suggesting a more nuanced understanding of nature’s complexities.
