In Finland, climate change causes the pine pest panolis flamea, or pine moth, to move its range north 50 years ahead of predictions. Changes in the distribution and population size of pine moths are linked to higher temperatures, according to a new study from the University of Eastern Finland. The findings were reported in Scandinavian Journal of Forest Research.
“This is not unexpected, as many scientists have already predicted that some insect pests will shift their range northward due to rising temperatures caused by climate change. However, what is amazing is that it happens 50 years before previous predictions,” says doctoral researcher Alexander Pulgarin Diaz from the University of Eastern Finland.
Pine moth larvae feed on the needles of different pine species across central Europe, developing periodic outbreaks often controlled with chemical insecticides. These outbreaks coexist with other pine insect pests and diseases and could reach thousands of hectares. No outbreaks have been reported in Finland, but conditions for their development may become favorable due to rising temperatures and declining forest health, two consequences of climate change.
Previous studies have shown that temperature is closely related to the development and distribution of insects. To study the distribution and population size of pine moths in Finland, the researchers coupled the number of individuals captured with heat sums from the previous year for the same location. For this, they used traps all over Finland and found that this pest insect had spread in northern Finland, up to 68°51’N. Additionally, they found that its abundance was higher in warmer places, such as southern Finland.
As climate change progresses and temperatures rise in Finland, the range and population density of the pine moth may also increase, allowing it to become a common and abundant pine feeder throughout the country. The results of this study on pine moth are consistent with previous findings on another major pine defoliator, the nun (Lymantria monacha), which has also increased significantly in Finland since 2000.
The study was funded by the Academy of Finland Flagship Program Forest-Human-Machine Interplay -Building Resilience, Redefining Value Networks and Enabling Meaningful Experiences (UNITE) (Decision No. 337127).