Crop pests are making their way toward the North and South Poles at a rate of about three kilometers — just under two miles — a year because of global warming. A new study in the journal Nature Climate Change has found that, largely as a result of international freight transportation, crop pests have been migrating away from the Equator. A warming climate means that they can now thrive in places previously uninhabitable to them and pose a major threat to global food security.
Currently, many crops are lost to fungi and fungi-like microorganisms as could feed nearly nine percent of the global population. 16 percent of all crop production is lost to pests including bacteria, viruses, insects, nematodes, viroids and oomycetes.
In the study, scientists from the University of Exeter looked at the distribution of 612 crop pests and pathogens for the past 50 years. They found that their migration into regions further and further away from the Equator corresponds to rising temperatures in the same period.
The mountain pine beetle is one such pest. Due to warmer temperatures, the beetle has been able to move to higher latitudes where it has destroyed large areas of the Pacific Northwest’s pine forests. Rice blast fungus or fusarium head blight, which is found in more than 80 countries and adversely affects agriculture and the health of ecosystems, has now moved to wheat and cost American farmers billions of dollars in lost crops. In Brazil, the fungus is already “sharply reducing” wheat yields.
Along with drought and extreme weather occurrences, farmers face more and more challenges. A long-term response to the rising numbers of crop pests in more and more places is not (sorry, Monsanto, Dow and other corporations) newer, “stronger” pesticides or genetically engineered crops that have been created to resist certain pests. Such crops are already fueling the evolution of “super-pests” who are resistant to pesticides: fields of identical crops can be all too readily wiped out.
In contrast, scientists have found that if you plant for genetic diversity, outbreaks of pests can be reduced. To feed a world whose population is expected to swell to around nine billion by 2050, we need to break away from crop monocultures and promote and preserve crop diversity, Vandana Shiva writes in the Guardian:
The tribals and peasants who gave us rice diversity wanted to evolve a rice for lactating mothers, a rice for babies, a rice for old people. They wanted to have rices that would survive droughts and floods and cyclones, so they evolved climate-resilient rices. In the Himalaya, different rices are needed for different altitudes and different slopes. The intimacy and care that go with belonging to a place and a community allows diversity to flourish.
The green revolution and the rise in the use of chemical pesticides have destroyed crop diversity, Shiva says, and caused unprecedented health problems. India is now the “capital of diabetes.” Shiva suggests that this has in part occurred due to the replacement of some 200,000 indigenous varieties of rice and wheat with a low glycemic index with industrial rice with a high glycemic index.
Citing statistics from the National Bureau of Crime Records, Shiva also points out that more than 284,000 Indian farmers have committed suicide since the time that “seed monopolies were established” in the country. With Monsanto controlling 95 percent of cotton seed, farmers who have come to rely on GMO Bt cotton have found themselves in debt and desperate.
The Nature Climate Change study makes clear that strains of crop pests are rapidly evolving. To ensure there is enough food to the earth’s growing population, we need to, as Shiva puts it, fight for “seed freedom” and to move away from the monoculture that comes with corporate control and creation of seeds. Otherwise, we could find ourselves living in a world planted from pole to pole with just a few types of crops that are constantly under threat from a growing array of hungry insects, types of fungi and many more creatures.
Photo of insect and wheat from Thinkstock; photo of pine mountain beetle via Wikimedia Commons