Human movement, particularly international freight transport, enables much of the movement of pests and pathogens, but climate change means that regions previously uninhabitable by new pests are now habitable – they are thriving where they have not previously been able to.
Fungi, insects, worms, bacteria, viruses, and other organisms have been moving ever-poleward since at least 1960 to escape the increasingly warm climes of their original home regions, a study has found. The study investigated the historical movement of 612 well-known crop pathogens. Though movement varied by species – some insects were moving as rapidly as 20km a year – the average movement was 3km annually.
Beyond the usual economic ruin and famine that routine 10-16% losses to pests spell, this movement is worrisome for another reason: as pests find newly comfortable homes in regions farther north and south than before, they also move into some of the world’s highest-yielding agricultural areas. Should these pests successfully move into high-yield areas, the losses we will suffer could have devastating consequences for global food security.
- Climate News Network Crop pests head polewards to flee heat
- BBC: Climate change ‘driving spread of crop pests’
- Nature Climate Change (subscription required): Crop pests and pathogens move polewards in a warming world