Scientists discover 'hibernating' fish for first time
Wednesday, 05 Mar 2008 17:26
The 'Antarctic cod' hibernates in winter
An Antarctic fish species undergoes a process similar to hibernation to survive winter, scientists have discovered for the first time.
The Antarctic 'cod' Notothenia coriiceps effectively 'puts itself on ice' during the long Antarctic winter, according to a team from the University of Birmingham and the British Antarctic Survey (BAS).
They found that the fish activates a seasonal 'switch' and goes from one ecological strategy that maximises feeding and growth in summer to another that minimises energy expenditure.
Some of the fish enter a dormant state similar to hibernation during the months of darkness and near-freezing water.
The discovery was made after researchers tracked the fish and monitored its heart rate in the wild.
"It appears they utilise the short Antarctic summers to gain sufficient energy from feeding to tide them over in winter," said Dr Keiron Fraser from BAS.
"The hibernation-like state they enter in winter is presumably a mechanism for reducing 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."
The research is published in the journal PLoS One.