Global Warming Warps Marine Food Webs
Teasing apart the complex ways in which global warming will affect ocean life has been tough. But new research suggests that a simple ecological theory may explain at least one piece of the puzzle: the effect on marine food webs. And the news may not be all bad.
New experiments confirm that phytoplankton, which form a bottom rung of oceanic food chains, will become less productive in warmer, nutrient-rich water. However, the results also show that zooplankton should boom in these warmer areas, which could benefit certain fisheries.
The food-web theory hinges on the assumption that temperature affects the metabolism of organisms that rely on other creatures for food, like zooplankton, while not having much of an impact on photosynthetic organisms like phytoplankton. That suggests that in warmer waters, zooplankton should generally grow faster and start reproducing sooner than they do in cooler waters. As zooplankton become more abundant and eat more phytoplankton, the population of phytoplankton should shrink.