MOSCOW, December 14. /TASS/. Researchers from the Siberian Federal University, the Krasnoyarsk Research Center from the RAS Siberian Branch, and the Center of Forest Protection of the Krasnoyarsk Region in collaboration with colleagues from NASA have discovered that global warming is responsible for a population boom of Siberian silk moths. The article with the results has been published in the journal Forests.
This dangerous pest has already occupied more than 800,000 hectares of the Yenisei boreal forests (taiga) and has moved further north than in previous years.
"The climate’s warming provides an opportunity for Siberian silk moths to migrate towards the northern territories of the taiga which were historically free of such swarms," the authors of the study wrote.
The Siberian silk moth is a butterfly, the caterpillars of which feed on fir needles of almost all conifers. Therefore, they are one of the taiga’s most dangerous pests. The trees damaged by this silk moth become weak and serve as an attractive target for other pests and diseases.
This sudden explosion of silk moths started in 2014. Researchers analyzed the satellite photos of the territories in question, data from ground-level research on the forests, and climate observations. The results of the analysis indicate that the area these pests now occupy, has expanded 50 kilometers northward, while the potential expansion zone has widened by another 150-300 kilometers. Scientists presume that the climate’s warming, the increase of its aridity, and the prolonged period of plant vegetation have brought about these circumstances, where the silk moth can easily migrate to the northern dark coniferous forests, hemlock forests, and highlands.
The previous spate of Siberian silk moths was seen in 1951-1957 in Ket-Chulymskoe interfluve area and in 1994-1996 in the Lower Angara region. However, the current population explosion, according to the scientists’ data, has already set a historic record regarding their expansion into the north.
Besides the silk moth, other pests have seen a boom in their numbers. These scientists tracked the huge upsurge in the Polygraphus proximus population, a type of bark beetle (https://en.wikipedia.org/wiki/Bark_beetle). Another consequence of this pest’s expansion is the increase of frequent and intense forest fires, as the dead trees are far more vulnerable to combustion.