In the fall of 2024, a remarkable event unfolded near the headquarters of Brazil’s Environmental Military Police. Thousands of orange and black-striped catfish, known as bumblebee catfish, began to scale the Sossego waterfall. This sight stunned researchers from the Federal University of Mato Grosso do Sul and the Pantanal Biopark, who rushed to witness this unusual migration of the rare species Rhyacoglanis paranensis. Their findings have sparked curiosity and excitement in the scientific community.
Manoela Maria Ferreira Marinho, one of the researchers, described the scene as incredible. “To see them out of the water, climbing huge rocks—it was unlike anything I’d ever seen,” she shared.
During the day, these fish were mostly hidden, but at night, they came alive. They swarmed from small pools, demonstrating an extraordinary drive to reach the waterfall’s top. Some catfish even crawled into researchers’ buckets, showing their eagerness to climb.
Bumblebee catfish are unique. While other fish like clingfish and gobies are known for climbing, this is the first documented case of bumblebee catfish scaling terrain in such large numbers. Researchers noted an intriguing feature: a small cavity on their bellies that might help them grip rocky surfaces. Ferreira Marinho emphasized that much remains unknown about this catfish genus.
There’s a general lack of data on fish migrations in Brazil, particularly for smaller species. Guido Miranda-Chumacero, a researcher with the Wildlife Conservation Society, previously observed a mass migration of pencil catfish in a Bolivian river. His work highlighted that local phenomena often go unreported, making the bumblebee catfish’s migration all the more significant.
Leading up to their climb, these fish might be motivated by breeding behavior or the search for better living conditions. Miranda-Chumacero pointed out that both the bumblebee catfish and the chipi chipi migrations coincided with heavy rainfall, likely influencing their movements.
Interestingly, catfish also exhibit homing behavior, meaning they have a natural ability to return to their birthplace. This has been well-documented in larger species like the goliath catfish, which can grow over six feet long.
The bumblebee catfish’s migration raises many questions—for instance, is this behavior seasonal? Why haven’t these migrations been documented before? Understanding these mysteries is crucial, especially as rivers in the region face threats from damming, which could obstruct these vital migratory paths.
As scientists continue to explore these questions, the story of the bumblebee catfish serves as a reminder of the wonders of nature and the secrets still hidden within our ecosystems.
