To read the original article in full go to : Thousands of bumblebee catfish captured climbing waterfall in never-before-seen footage.
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Thousands of Bumblebee Catfish Climb Waterfall in Brazil, Revealing Rare Upstream Migration
Live Science reports a remarkable observation: thousands of bumblebee catfish (Rhyacoglanis paranesis) were filmed climbing a waterfall behind the Aquidauana River in Mato Grosso do Sul, Brazil. The tiny fish, about 3.5 inches long, formed a mass ascent as light faded, hinting at an upstream migration related to reproduction. The study, published August 8 in the Journal of Fish Biology, describes their vertical climbs on rocks, sometimes piling on each other, and notes the behavior begins in the late afternoon when the heat wanes. The researchers point to the potential importance of this migration for the species and warn that damming and habitat fragmentation could threaten such life-cycle needs for small river fishes.