Pests on the Rise in a Warmer World

November 16, 2009

The effects of climate change will be far reaching and pervasive. But what does that really mean? Well, you can’t really explain it in one blog post, but you can give a great example that will make you squirm: a warmer world means more pests. An AP article offers its insights on some of the bugs and bug-a-boos that may be more prevalent as the temperatures rise.

Ticks that transmit Lyme disease are spreading northward into Sweden and Canada, once too cold for them. Giant Humboldt squid have reached waters as far north as British Columbia, threatening fisheries along much of the western North American coast. Malaria-carrying mosquitoes are now found in South Korea, the Papua New Guinea highlands, and other places previously not warm enough for them. Bark beetles reproducing more quickly in warming climates and expanding their ranges have devastated forests across western North America. In British Columbia they have laid waste to an area twice the size of Ireland. A microscopic parasite is spreading a deadly disease among salmon in Alaska and British Columbia. Researchers say rising water temperatures are partly to blame. The U.S. government warns that such invasive plants as the common reed, hyacinth and purple loosestrife are likely to spread to northern states.

The big question that arises when you see a list like this is, why? The answer is that for some species, the changes in temperature, more specifically the extreme cold days in winter, act as a ‘population equalizer.’ With temperatures even a little bit warmer, fewer pests freeze and die naturally, leaving more to reproduce. This is particularly the case with bark beetles in Canada which also reproduce more rapidly in warmer temperatures. Fight climate change now. Reduce and offset your carbon footprint.