Hi!
Many fishes in the polar region do produce antifreeze compounds, which protect them from freezing. There is another factor which helps them to survive and that is Water. The density of water decreases below 4 degree Celsius and ice therefore tends to float over water. Since ice floats, it is formed at the surface first. Ice formed at the surface insulates the water below it, thus increasing the chances of survival of organisms in cold water.
@sujata: Very good! Keep up the good work.
