Climate Change Drives Spread of Crop Pests: Serious Impacts for Food Security

Climate change may have some serious impacts for farmers. It turns out that as the climate shifts, more and more crop pests are spreading. In fact a new study has shown that these pests are moving at a rate of nearly two miles per year toward the North and South Poles. The findings could have major implications for food security in the future.

Pests are a major concern for farmers. Currently, about 10 to 16 percent of global crop production is lost to these creatures. Including a range of species such as fungi, bacteria, viruses, insects, nematodes, viroids and oomycetes, these pests continue to expand as new strains continue to evolve. In fact, losses of major crops to fungi and fungi-like microorganisms amount to enough to feed nearly nine percent of today's global population. Needless to say, that's a lot of food.

In order to learn a little bit more about how crop pests might spread and affect our food security in the future, the researchers examined published observations of the distribution of 612 pests collected over the past 50 years. In the end, they found that pests were moving north and south toward the poles and even into previously un-colonized regions.

"Renewed efforts are required to monitor the spread of crop pests and to control their movement from region to region if we are to halt the relentless destruction of crops across the world in the face of climate change," said Sarah Gurr, one of the researchers, in a news release.

Pest spread is caused by both human activities and natural processes. Yet most believe it's primarily the result of international freight transportation. In combination with a warming climate, though, these pests are becoming established in previously unsuitable regions. For example, warming stimulates insect herbivory at higher latitudes, such as the pine beetle which has destroyed vast swathes of pine forest in the U.S. Pacific Northwest.

"If crop pests continue to march polewards as Earth warms the combined effects of a growing world population and increased loss of crops to pests will pose a serious threat to global food security," said Dan Bebber, one of the researchers in a news release.

The findings are published in the journal Nature Climate Change.