Lipids and life strategies of Calanus finmarchicus, Calanus glacialis and Calanus hyperboreus in late autumn, Kongsfjorden, Svalbard

Stage IV and V copepodites were the dominant forms of Calanus finmarchicus, C. glacialis and C. hyperboreus in Kongsfjorden in late September 1997. St age IV and V copepodites of C. glacialis and C, hyperboreus were rich in li pid, largely wax esters, and were well fitted to overwinter. Stage IV copep odites of C. finmarchicus were also rich in wax esters, but stage V copepod ites of C. finmarchicus were less wax ester-rich. Large size increments bet ween stage IV and V copepodites and between stage V copepodites and females were noted in C. finmarchicus. A very large increment between stage IV and V copepodites was noted for C. glacialis but the size difference between s tage V copepodites and females was very small in this species. Particularly large increments were noted between stage IV and V copepodites of C. hyper boreus and also between stage V copepodites and females of this species. Th e very large, wax ester-rich C. hyperboreus is well adapted to survive the most extreme variations in the Arctic. in Arctic basin waters. whereas the smaller, wax ester-rich C. glacialis is adapted to survive less extreme Arc tic variations, as in Arctic shelf waters. The smallest of the three. C. fi nmarchicus, is best adapted to survive the more predictable waters of the N orth Atlantic and the Barents Sea.