Intestinal study shows how climate change may affect Arctic fish

As sea temperatures rise, stocks of some fish species may decline while others may increase, says a May 14 news release about a Swedish research project.

It found the gastro-intestinal system in fish is much more sensitive to temperature changes than previously believed and may prevent some species from moving around.

By looking at how rapid and slow changes in water temperature affect gut function in various fish species, researcher Albin Gräns wanted to see what could happen to different species when the climate changes.

For his research, he studied sculpin, sturgeon and rainbow trout in western Sweden, California and Greenland.

Because the body temperature of almost all fish is the same as that of their surroundings, when the temperature of the water changes, so does the temperature of the fish, which affects all their body functions.

“When the temperature of the water rises, the fish’s body temperature climbs, activity in the gut increases, and more energy is needed to stay healthy,” said Gräns in the release.

Gräns found some fish species may find it harder to absorb nutrients as water temperatures rise, while others may benefit from the new conditions.

“If the water temperature in the Arctic rises further, some sedentary species, such as various types of sculpin, will probably struggle to maintain blood flow in the gut during the summer months, which will affect their health,” he said in the release.