Ontogeny of Feeding Behavior of First-Feeding Atlantic Salmon ( Salmo salar )

• Published in: Canadian Journal of Fisheries and Aquatic Sciences
• Main Author: Coughlin, David J.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Canadian Science Publishing 1991
• Subjects: Aquatic Science; Ecology, Evolution, Behavior and Systematics; Atlantic salmon; Salmo salar
• Online Access: http://dx.doi.org/10.1139/f91-225; http://www.nrcresearchpress.com/doi/pdf/10.1139/f91-225

Feeding strikes of Atlantic salmon (Salmo salar) alevins preying upon Daphnia are described using videorecording of synchronous lateral and antero-ventral views. Based on examination of characteristics such as aiming inaccuracy and capture distance, it is demonstrated that feeding behavior significantly improves during the first 2 wk after initiation of exogenous feeding. With increasing experience, young salmon tend to capture prey more quickly and with greater accuracy. First-feeding alevins use a body-ram feeding mode, relying on their swimming motion to overtake and capture prey. After 7–10 d of feeding, the fish change to a suction feeding mode that effectively uses suction generated by expansion of the orobranchial chamber to pull in prey from a distance. Also, feeding behavior of alevins raised on a commercial salmon feed lags developmentally behind the behavior offish raised on live food. This lag time is short (2–3 d), indicating that despite reports to the contrary, hatchery-raised fish do not require a Song time to learn to capture prey effectively in the wild.