When it comes to changes in temperature, numerous marine species are among the most vulnerable. Mammals have evolved a clever mechanism whereby they can regulate their internal temperature to a level that is relatively constant and comfortable, making them a little less dependent on their environment to keep their core body temperature stable.
Cold-blooded animals are not quite that efficient. They are dependent on the temperature of their surrounds to keep their metabolism in full working order. Locked into a specific set of thermal requirements, they respond immediately to change. Like many terrestrial species, fish are expected to respond to changes in the temperature of the environment around them by shifting their distribution. Fish from the tropics are likely to push south along our coast. Many fish from temperate latitudes might try to head for deeper waters, but could find their migration inhibited by water currents.
By Leonie Joubert