https://onlinelibrary.wiley.com/doi/abs ... /jfb.14459
ABSTRACT
The spotted surubim is a large migratory catfish native to the La Plata and San Francisco basins. However, its reproductive dynamics and behavior remain poorly understood. In this brief note, we provide the first record of the mating behavior of P. corruscans in natural conditions. This event was observed in the main channel of the Middle Uruguay River (Brazil). We followed and videotaped a school of approximately 25 fish, being five females (protruding abdomen and larger body size) and twenty males. The largest female led the school, followed by other fish. Males disputed repeatedly the posterior region of the females, while other males continuously repelled them. Eventually, some males, apparently exhausted, floated belly up. During this event, males were in state of pronounced agitation, and some had abrasions in the head. Polygamy characterized the mating behavior of P. corruscans.
