Salmon or trout?
Atlantic salmon, Salmo salar and brown trout, Salmo trutta are two closely related salmonid species that are often mistaken for one another. At the juvenile stage they can be tricky to tell apart, especially given that the classic trout/salmon ‘markers’ may not always be clear or present in every individual. For example, one frequently used marker is red colouration in the adipose fin which identifies an individual as trout and no red as salmon, however occasionally some trout lack this colouration as well and the frequency of which this occurs varies locally. Therefore, it is recommended to use several indicators. Here we can see some of the commonly used indicators:
Written by Madeleine Berry, PhD student with the SEG.