Warming seas may imperil Antarctic fish

William Detrich, professor of biochemistry and marine biology in the College of Scienceat Northeastern University, has been awarded $639,000 from the National Science Foundation (NSF) to advance his research on the effects of global warming on Antarctic fish and the role of these fish in the Antarctic food chain.

For roughly 8 million to 10 million years, the seawater in the southern ocean surrounding Antarctica held a stable temperature of -2 °C (28 °F). But now, due to global warming, the seawater is rapidly heating up, Detrich said.

“The ancestors of today’s Antarctic fish evolved so that the frigid temperature was quite comfortable,” he said. “In fact, their body temperature matched that of the water. But now their habitat is experiencing unprecedented and rapid warming.”

With dramatic increases in ocean temperature occurring near the Antarctic Peninsula, Detrich said the warmer water will affect many of the biological processes in these fishes’ cells, tissues, organs, and even behavior.

The NSF grant will enable Detrich to continue his research for another three years, to discover precisely how Antarctic fish will be affected at these different systemic levels.

“Will embryos develop faster and hatch during winter darkness before their food — primarily phytoplankton — becomes available in the spring?” he asked. “Or will the warm environment perturb their development and perhaps lead to death, ultimately causing local extinction of these important components of the Antarctic food chain?”

Antarctic fish are intermediate in the Antarctic food chain and are eaten by seals, birds, and even killer whales. Mammals and birds, which are near the apex of the food chain, could suffer if this part of their diet were to decline.