Hibernation in an Antarctic Fish: On Ice for Winter

• DOI: 10.1371/journal.pone.0001743
• Publication Date: 2008-03-04T22:58:37Z
• Authors: Hamish A. Campbell; Keiron P. P. Fraser; Charles M. Bishop; Lloyd S. Peck; Stuart Egginton
• Keywords: Hibernation

Active metabolic suppression in anticipation of winter conditions has been demonstrated species mammals, birds, reptiles and amphibians, but not fish. This is because the reduction rate fish directly proportional to decrease water temperature they appear be incapable further suppressing their independently temperature. However, Antarctic (Notothenia coriiceps) unusual it undergoes irrespective We assessed seasonal ecological strategy by monitoring swimming activity, growth, feeding heart (fH) N. coriiceps as free-ranged within sub-zero waters. The wild was extrapolated from fH recordings, oxygen consumption calibrations established laboratory prior release. Throughout summer months spent a considerable proportion its time foraging, resulting growth (Gw) 0.18±0.2% day−1. In contrast, during much sedentary refuge showed net loss Gw (−0.05±0.05% day−1). Whilst inactive winter, displayed very low fH, reduced sensory motor capabilities, standard one third lower than summer. similar manner other hibernating species, dormancy interrupted with periodic arousals. These arousals, which lasted few hours, occurred every 4–12 days. During arousal metabolism increased levels. endogenous activation processes, independent body temperature, demonstrates that were effectively 'putting themselves on ice' until food resources improved. study at least some can enter dormant state hibernation driven presumably provides energetic benefits.