Crop Pests Will Likely Spread Toward Poles As Earth Continues To Warm
September 2, 2013

Crop Pests Will Likely Spread Toward Poles As Earth Continues To Warm

Lee Rannals for - Your Universe Online

A new study published in the journal Nature Climate Change suggests that global warming could help crop pests spread toward the North and South Poles.

The team said that global warming is causing crop pests to spread toward the poles at a rate of nearly 1.8 miles per year. Currently, pests are taking down about 10 to 16 percent of the global crop production, but if the global warming trend continues then this percentage will only climb higher.

The researchers based their findings on 50 years of data that included global temperatures and the range of crop pests, which includes fungi, bacteria, viruses, insects, nematodes, viroids and oomycetes. They said the diversity of crop pests continues to expand and new strains are constantly evolving.

The amount of crops lost to fungi and fungi-like microorganisms is enough to feed nearly nine percent of the global population. The study shows that these figures will continue to increase if the temperatures rise as predicted.

A warming climate is allowing for pests to become established in previously unsuitable regions. This warming generally stimulates insect herbivory at higher latitudes as seen in outbreaks of the mountain pine beetle, which has overtaken huge swaths of forest in the US Pacific Northwest. Another example is the rice blast fungus, which is present in over 80 countries. This fungus has now moved to wheat and is sharply reducing wheat yields in Brazil.

"If crop pests continue to march polewards as the Earth warms the combined effects of a growing world population and the increased loss of crops to pests will pose a serious threat to global food security," said Dr Dan Bebber from the University of Exeter.

The team found that the movement of pests north and south towards the poles and into previously uncolonized regions corresponds with increased temperatures due to climate change.

"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 Professor Sarah Gurr from the University of Exeter.

Last year, scientists said as the planet's population continues to grow, food shortages could cause everyone to move to a vegetarian diet. However, if higher temperatures continue to spread then moving everyone from a meat to a veggie diet could become another problem altogether.