News Release

Antarctic fish study may aid cardiac research

Antarctic 'cod' clues to climate change

Peer-Reviewed Publication

British Antarctic Survey

A species of fish that lives in Antarctic waters may hold clues to climate change and lead to advances in heart medicine. Researchers from the University of Birmingham and the British Antarctic Survey (BAS) are investigating the behaviour and physiology of the 'Antarctic Cod' (Notothenia coriiceps) which became isolated from its warmer water cousins around 30 million years ago when the Antarctic circumpolar current was formed.

The olive-coloured fish has broad head and a narrow body. Whilst scientists know that it has 'antifreeze' in its blood and maintains a very low heart rate of less than 10 beats per minute, almost nothing is known about its behaviour or how it evolved to live in Antarctica's extreme environment.

Discovering how the species may cope with predicted environmental change could help stock management or conservation of biodiversity within the Southern Ocean. In addition, it is possible that this research could lead to advances in medicine, especially relating to the problems experienced by human hearts when made to beat slowly (e.g. during surgery involving heart-lung bypass) or fail to beat fast enough (e.g. as a result of hypothermia in water or exposure on a mountain).

At the BAS Rothera Research Station on the Antarctic Peninsula small acoustic tags (called 'pingers' due to the sound they make) are painlessly attached to the fish and the signals picked up by underwater microphones to monitor position, while data loggers measure heart rate. In the laboratory, Dr Hamish Campbell, monitors heart performance of the fish in a similar manner to that used with patients in a chest pain clinic. The unique combination of tracking and recording technology shows how the heart rate is controlled, and its response to changing demands due to feeding or a rise in temperature.

Physiologist Dr Stuart Egginton, from the University of Birmingham's Medical School is leading the study: He says,

"This pioneering work will shed light on what animals get up to during the impending 24h darkness of a polar winter, how sensitive they are likely to be to climate change, and perhaps pave the way to understanding how we may prevent a cold heart from fluttering. We know enough to realise this 'cod' is different from those species living in the chilly North Sea, but not enough to be sure whether its strange characteristics are a response to the extreme cold, or because it is a descendant of unusual ancestors that has developed this way during its extended isolation from other fishes".

Dr Keiron Fraser from BAS says, 'This is the first time that we've been able to find out how these fish live. Many Antarctic marine animals can live only within narrow temperature ranges and some die at around +5°C. Climate models predict a 2ºC rise on global sea temperatures over the next 100 years. One of the areas that we are trying to understand is how this fish species will respond or adapt to major environmental stresses, and how well it may survive the predicted environmental warming.'

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Issued by BAS & Birmingham University Press Offices

Contacts: British Antarctic Survey - Linda Capper, Tel: 44-122-322-1448, mobile 44-771-423-3744 or Athena Dinar, BAS Press Office. Tel: 44-122-322-1414; mobile: 44-774-082-2229

University of Birmingham - Abigail Dixon, Tel: 44-121-414-5134, mobile 44-778-992-1163

Science Contacts: Dr S. Egginton, Department of Physiology, University of Birmingham Medical School. Tel: 44-121-414-6902. email: s.egginton@bham.ac.uk

Dr Stuart Egginton has been working on research projects in Antarctica since 1989. Papers of his work have been published in the American Journal of Physiology, the Journal of Experimental Biology and the Journal of Fish Biology.

Dr Keiron Fraser, British Antarctic Survey. Tel 44-122-322-1329; email: k.fraser@bas.ac.uk Mobile 44-781-277-8031

Dr Hamish Campbell, from the University of Birmingham is conducting this study over two Antarctic summers and one entire winter period at Rothera Research Station. He returns to UK in March 2005. To arrange interviews with him contact the BAS Press Office. Please note Rothera is 4 hours behind UK time.

Notes to Editors:
Video news release including visuals of Antarctica + interviews with Dr Hamish Campbell and Dr Stuart Egginton is available free of charge as a package from Research TV. This is due for streaming via APTN on Tues 30 March between 12.45-1255. www.research-tv.com. Or Contact: Lucy Handford – L.handford@warwick.ac.uk Tel: 207-799-3668.

British Antarctic Survey is a component of the Natural Environment Research Council and is responsible for the UK Government's research in Antarctica. For more information about the British Antarctic Survey and the Rothera Research Station look at our website www.antarctica.ac.uk

The collaborative research is part of the British Antarctic Survey (BAS) Antarctic Funding Initiative (AFI), which promotes wider participation in Antarctic research by UK universities and other research organisations. AFI encourages field-based research carried out in the normal BAS operating area and using the unique logistic capabilities of the Survey.

Climate records from the Antarctic Peninsula region show that annual mean temperatures have risen by nearly 3°C during the last 50 years - a far larger rise than seen elsewhere in the Southern Hemisphere. Antarctic marine animals can live only within narrow temperature ranges and many die at around +5°C. Understanding how well the 'Antarctic cod' may cope with the predicted environmental change could help stock management or conservation of biodiversity within the Southern Ocean.

Global climate model predictions of how the Antarctic climate may change over the next 100 years differ in detail from model to model. Although climate models predict an enhanced response to future global warming in some parts of the polar regions, the Antarctic Peninsula is not one of these areas. Weakness in current climate models do not show a clear association between Peninsula warming and global warming and it is premature to attribute warming in the Peninsula to an enhanced "greenhouse" effect. (see BAS Position Statement on Antarctic Climate Change – www.antarctica.ac.uk).

British Antarctic Survey is conducting a range of science programmes investigating this important global issue including biological research on plant and animal communities around Rothera Research Station.

Antarctic Nototheniid, known as Antarctic cod but are not true cod, live in close proximity to ice have evolved a glycoprotein antifreeze in their body fluids to prevent freezing.

The University of Birmingham's researchers are based in the newly formed Centre for Cardiovascular Sciences. For more information on the University of Birmingham's School of Medicine see www.medicine.bham.ac.uk


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