Zooplanktons - tiny marine animals - use the oxygen minimum zones as refuges from predators, migrating vertically down into the zone during the day and returning at night to feed in the oxygen and food-rich areas closer to the surface.
But now, these oxygen minimum zones are predicted to expand into shallower waters as global warming continues, which will force the zooplankton into a narrow band of water during the night and making them susceptible to their main predators - fish, according to a new research.
"Oxygen minimum zones are very difficult places to survive," said University of Rhode Island doctoral student Leanne Elder.
"But we have discovered that these tiny animals have adapted in two specialized ways.
"First, they suppress their metabolism, which is very much like hibernation in other animals. Second, while converting food into energy normally requires large amounts of oxygen, these zooplankton use a different process - anaerobic glycolysis - which allows them to use only small amounts."
If this causes a population crash in these animals, it will have impacts all the way up the food chain, says Elder.
The study will be presented at the annual conference of the Society for Experimental Biology in Glasgow, Scotland.