Within each upper shelf habitat that supports a C. gunnari population, there appear to be migrations throughout development. Most juveniles (<15 cm) were found in the southern and eastern part of the shelf, or otherwise inshore regions. As fish grow older, they moved to the north of the shelf. Only the oldest fish were observed in the deepest, which corresponded to the most north, sections of the shelf. (Kock 2005a)
While it is still possible that migrations between shelf habitats of the mackerel icefish exist, there has been no report of the in pelagic waters beyond any of the shelf breaks. Also, clear genetic differences have been observed, even between three populations close enough to migrate, making migrations of C. gunnari less likely. (Kuhn 2006)