Insect activity, crop losses could increase as global temperatures rise

September 10, 2018

When temperatures go up, so do certain risks, like the potential presence of certain crop and shellfish toxins. Alongside these risks, a new study outlines how insect activity also increases as the globe heats up — leading to increased crop loss.

Research from the University of Washington suggests that a rise of just 2°C can lead to total losses of 213 million tons in some of the world’s most important crops: corn, wheat and rice. Why? Because of increased bug activity.

“We expect to see increasing crop losses due to insect activity for two basic reasons,” said study lead Curtis Deutsch. “First, warmer temperatures increase insect metabolic rates exponentially. Second, with the exception of the tropics, warmer temperatures will increase the reproductive rates of insects. You have more insects, and they’re eating more.”

The study involved compiling a lot of data. Researchers analyzed decades of past studies on insect metabolic and reproductive rates, including information from both inside and outside the laboratory.

The problem here with insects is that they’re ectothermic, or cold-blooded. This means that their body temperatures are greatly affected by the temperature of the air, which in turn impacts their oxygen consumption, appetites and metabolism. If you live in or have ever visited a warm, tropical area, you’ve probably noticed how common bugs are.

The researchers say their data shows that this is true for major pests like aphids and corn borers, and that losses will likely differ by crop. With a rise of 2°C in global surface temperatures, they predict losses of 19% for rice (which is already predominately grown in warmer regions), 31% for corn and 46% for wheat.

The study authors fear that as global populations skyrocket, increased insect activity could negatively impact global food security, meaning it will be more difficult to feed the world’s hungry mouths.

“It appears that under virtually all climate change scenarios, pest populations will be the winners, particularly in highly productive temperate regions, causing real food prices to rise and food-insecure families to suffer,” said study author Rosamond Naylor.

Category: Agriculture, Milling & Grain, Professional Pest, Insect Control