Climate change has already had unprecedented, world-altering effects on virtually every aspect of life on Earth, and pest life is no exception. As the world’s temperature goes crazy, insects and pests of all kinds are scrambling to acclimate. Their changing behavior already had huge consequences all over the world. They’re only going to become even more significant going forward.
So: how are pests affected by climate change, exactly? What about the permanent alteration of the world’s temperature causes them to behave differently? What do these behavioral changes affect? Here are a few ways global warming is changing pests forever, and how we’ll be affected in turn.
In most cases, an insect’s home distribution range is determined almost exclusively by temperature. Bugs don’t migrate anywhere that’s too hot or cold, so there’s less species diversity at high and low latitudes. Climate change is slowly warming temperatures all over the world, however–including in northern and southern latitudes and areas of high elevation. Regions that once would have been too cold for insects will now comfortably host them. They’ve noticed.
When insect species migrate to regions where they’ve never lived before, the ecosystem isn’t prepared for them. Pests will do far more damage than is natural, far faster. The mountain pine beetle, southern pine beetle, and hemlock wooly adelgid have all inflicted significant damage on the forests they’ve suddenly moved into. The most dangerous poisonous spider in North America, the brown recluse, may have expanded its range further north than ever before. Even now, it’s clear that insect migration caused by climate change is significantly altering the balance of nature all over the world.
The life cycles of many insect species revolve around winter. Mosquitoes, wasps and bees, beetles, flies, and more grow, feed, and reproduce when they do to prepare for winter. When winter comes, it generally kills off the entire generation of insects. Then, the offspring conceived in fall emerge in the spring, and they replace the previous generation. The cycle begins again, and the numbers stay largely consistent.
In many parts of the world, climate change has affected the severity of winter. In regions where winter has become more mild, it’s easier for insects to survive. Insects like mosquitoes and pine weevils can live until spring. These survivors still foster offspring the way they normally do, which means greater insect populations for the rest of the year. Insect life cycles are so short that the effect of milder winters has already had a huge impact on species population dynamics. If insects keep surviving winter, their populations will just keep climbing.
As if the mild winters weren’t bad enough, climate change has accelerated insect population growth in other ways, too. Insects are cold-blooded, so temperature is the most important determinant of their activity level. Warmer temperatures correlate with higher daily and seasonal insect activity, longer feeding periods, and faster reproductive cycles. Scientists estimate that a temperature difference as small as two degrees celsius could result many insect species completing one to five additional life cycles per season.
Insects are living longer, traveling further, and reproducing more. It all adds up to a huge increase in pest population. As seasons go by and more pests survive to continually reproduce and enjoy the milder weather, insect population growth will accelerate exponentially. Factor in the pest’s access to new food sources, and it’s easy to understand how real a problem this is.
It’s difficult to overstate just how much climate change can, will, and has changed life on Earth. The rapid life cycle of pests mean climate change affects them quickly. In other words, pests may serve as the “canary in the coal mine” for coming climate changes. Going forward, pest control will be more important than ever–on large and small scales.
Whether it’s attempting to keep mosquito populations down all over Africa or just keeping a gross centipede out of your home, pest control is all about managing where pests go. If you ever need some help controlling your pest problem, give Plunkett’s a call any time. We may not be able stop climate change (if only!), but we can definitely handle whatever you’ve got to throw at us.BACK TO BLOG