Hibernation-Like Behaviour in Antarctic Fish
06.03.2008 - Other
Scientists from the British Antarctic Survey (BAS) and the University of Birmingham have discovered that the Antarctic cod Notothenia coriiceps adopts a survival strategy similar to hibernation, thereby saving energy during the long Antarctic winter.
This study demonstrates that Antarctic fish with extremely low rates of growth, metabolism and swimming activity - can in fact further depress these metabolic processes in winter. Fish are generally incapable of suppressing their metabolic rate independently of temperature. The interesting thing about these Antarctic cod is that their metabolic rates are reduced in winter even though the seawater temperature doesn't decrease much. However, seasonal light levels vary enormously, alternating 24-hour light periods during the summer with months of winter darkness. The decrease in light during the wintertime could thus be responsible for the reduction in metabolic rates.
The hibernation-like state they enter in winter is presumably a mechanism that allows them to reduce their energy requirements to the bare minimum. The interesting question we still have to answer is why these fish greatly reduce feeding in winter when food is still available.
