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Fishy tales at Davis
26 November 2001
Hanging out in an IRB off Magnetic Island. Photograph by J. Downs
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During the past 11 months marine ecologist, Jacqui, has been researching the properties of 'antifreeze' proteins contained in the blood of Antarctic cod and icefish (notothenioid fish ).
The cod species most frequently found in fish traps in the shallow waters around Davis. Photograph by J. Downs
 | Based at Davis since last summer, she has collected more than 180 fish with the help of many on station. After taking the necessary blood samples and then preserving the fish bodies, she is now preparing to depart on the Polar Bird on voyage 4, due within a couple of days. In her last few days this week, Jacqui plans to make one last fishing trip.
Back in Australia, the serum she has collected will be tested in laboratories to determine what antifreeze proteins are in the blood that allow the fish to survive in water that is colder than the usual freezing point of their body fluids.
Once identified, these molecules may be synthesized in the laboratory for use in many potential practical applications, from the preservation of frozen foods, of blood plasma and organs for human transplant.
Jacqui 's year has been very productive and contained many highlights. During the summer months, most fishing was carried out in small boats.
Catching a fish in the IRB. Photograph by S. Basson
 | "Fishing during the summer never seemed like hard work. The weather was, more often than not, superb and there were plenty of distractions out on the water.
Apart from incidents like Brian somehow miraculously being able to snag two icefish on the same line, bringing his share of the day's total catch to a ridiculous 8 out of 11 fish, we were also treated on the odd occasion to whale sightings (usually Minkes), leopard seals or an 'attack' from rogue Adelie penguins.
The latter were always extremely amusing. For some reason, best known to themselves, groups of Adelies would sometimes see an IRB, circle it and then suddenly come hurtling out of the water at great speed only to land with a thud in the bottom of the boat, fly over the bow or dive straight into someone's back; all presumably, because we had been mistaken for an ice flow. Often when the shock of landing in unknown territory finally hit home, there would be much panic, flipper flapping and squawking, while others were rendered immobile out of sheer terror. One or two, however, appeared to be totally unfazed by the experience and remained in the boat, seemingly happy to be with us taking in their new surroundings for a time.
The most memorable of these incidents happened towards the end of summer. I happened to be with the leopard seal team ... it had been an uneventful day seal-wise, and we had just turned off the motors, tied the two IRBs together and were settling down for lunch.
The calm was soon shattered by a succession of 30 to 40 Adelies launching themselves into the boats. Not surprisingly, this turned our attempts at eating lunch into a complete farce! Trying to stuff food into your face when you are being pummeled from several directions at once just doesn't work!"
Jacqui's project relied on the support of others on station, for volunteers to go fishing (never a shortage there), to assistance in developing new ways of fishing as the sea and ice conditions changed with the seasons.
Deploying a fish trap through the ice from the wharf at Davis. Photograph by J. Downs
 | As the sea ice began to form with the onset of winter, Jacqui was no longer able to use boats, and found herself continually developing different ways to make holes in the ice, through which she could deploy her fish traps.
No sooner had I mastered the art of utilizing the 'heavy chunk of steel' (hurled from the shoreline to break a hole in the ice), than the ice was strong enough for us to walk on. However, it had become apparent that the traps that I had been using up until this time would no longer be appropriate for the new methods of fishing hole construction I would have to adopt. The diesos then came to the rescue and soon whipped up a new lot of traps. Days later , the muscle powered ice drill made its appearance and the new traps deployed.
Quad and sled are used to transport jiffy drills and fish trips to sites further afield. Photograph by J. Downs
 | With the onset of winter, the ice continued to thicken. As it did, the manually operated ice corer gave way to the petrol powered jiffy drill. Soon quads and Hagglunds were able to be employed to travel across the sea ice to transport equipment to various sites offshore, further away from the station.
As spring approached and the ice began to break out, Jacqui's fishing efforts were once again constrained to the ice edge, an excellent vantage point from which to see the return of the wildlife (birds, seals and penguins) for breeding.
Fishing at the ice edge at this time was a real treat. I think I must have one of the best jobs down there!
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