Canadian forests are being hit hard by an outbreak of the mountain pine beetle. Though the beetles are small — less than 1/3 of an inch long — they are very hungry, boring through the wood of a variety of pine tree species.
The severe outbreak of the beetles in Canada is killing enough trees that ecologists are worried that forests in British Columbia could change from being a "carbon sink" — absorbing carbon dioxide emissions and sequestering them — to a carbon source — releasing stored up carbon dioxide as the trees die and decompose or burn in forest fires. Warming temperatures are allowing the beetles to spread into new territory, threatening more forests.
"The current outbreak in British Columbia, Canada, is an order of magnitude larger in area and severity than all previous recorded outbreaks," researchers write in the journal Nature. They found that one outbreak of the beetle alone released enough carbon dioxide to equal five years worth of emissions from transportation sources in Canada.
Werner Kurz, a senior research scientist at the Canadian Forest Service, talks about how a tiny beetle could have a significant impact on the carbon balance in North America.