Global warming could spur more and hungrier crop-eating bugs
WASHINGTON (AP) — A warmer world likely mean more and hungrier insects chomping on crops and less food on dinner plates, a new study suggests.
Insects now consume about 10 percent of the globe's food, but that will increase to 15 to 20 percent by the end of the century if climate change isn't stopped, said study lead author Curtis Deutsch, a University of Washington climate scientist.
The study looked at the damage bugs like the European corn borer and the Asiatic rice borer could do as temperatures rise. It found that many of them will increase in number at key times for crops. The hotter weather will also speed up their metabolism so they'll eat more, the researchers report in Thursday's journal Science. Their predictions are based on computer simulations of bug and weather activity.
"There's going to be a lot of crop loss, so there won't be as much grain on the table," said study coauthor Scott Merrill, an ecology professor at the University of Vermont.
The researchers calculate additional losses of 53 million tons (48 million metric tons) in wheat, rice and corn from hungry bugs if the temperature rises another 2.7 degrees (1.5 degrees Celsius) from now. The study estimates that in that warmer scenario, American corn, wheat and rice losses from insects will jump by a third above current levels. Bug damage to Russia's rice crop would jump sixfold. And nine countries — North Korea, Mongolia, Finland, Kyrgyzstan, Georgia, Bhutan, Armenia, the United Kingdom and Denmark — would see at least a doubling of wheat loss from bugs.
If there are no drastic cuts in emissions from coal, oil and gas, the world will reach that 2.7 degree mark and extra insect loss around 2050 — give or take a decade or so, Deutsch said.
"In the history of agriculture, one of the most important themes is the continuing struggle between farmers and insects," said Stanford University environmental institute director Chris Field, who wasn't part of the study. "Based on this study, climate change tilts the balance in the insects' favor."
The Russian wheat aphid is a good example because "the populations are absolutely insane ... they are born pregnant," Merrill said. "If you increase the temperature a couple degrees you can see the population growing much faster."