Bibliographical reference – how to cite this fact sheet: Fiske, P. (2012): NOBANIS – Invasive Alien Species Fact Sheet – Salmo salar. – From: Online Database of the European Network on Invasive Alien Species – NOBANIS www.nobanis.org, Date of access x/x/2

• Main Author: Salmo Salar
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: Atlantic salmon; Salmo salar
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.671.2015; http://nobanis.org/files/factsheets/salmo_salar.pdf

Fig. 1. Escaped farmed salmon (Salmo salar) (right) often show wavy fin rays, while wild salmon (left) has more even rays, photos by Roar A. Lund. Fig. 2. Salmon that recently has escaped from net pens (right) often have rounded tails, while wild salmon (left) have more sharp tails, photos by Roar A. Lund. Species identification The appearance of Atlantic salmon changes from the juvenile freshwater stage, via a silvery stage in the ocean to a more ornamented appearance close to spawning in the rivers. Adult Salmo salar in the sea has silvery sides and belly, and a darker back. They normally have relatively few spots below the lateral line, a relatively slender caudal peduncle (tail root), and a v-formed tail. Salmo salar and sea-trout (Salmo trutta) may be difficult to separate, especially large individuals. Farmed salmon look similar to their wild con-specifics, but they often have worn fins with wavy fin-rays and more spots both above and below the lateral line than wild salmon. Thus, farmed salmon may at occasions look similar to sea trout. Furthermore, the growth pattern in the scales distinctively separates farmed from wild salmon (Lund and Hansen, 1991; Fiske et al., 2005a). Native range