Insect numbers, which account for 60% of species in European forests, have decreased significantly. Reported by TASS.
Insects are one of the most diverse groups of animals, providing many ecospheric services, cleaning areas from carrion and diseased trees, serving as food for mammals and fish, and also participating in the pollination of plants. Many insects are threatened by habitat destruction and global warming. So in just the last 6 years, the number of European wasps has decreased by 1/3.
Now, Michael Staab of the Dresden University of Technology and his colleagues have decided to find out how the insect populations are doing in European forests. The analysis was based on observation of German forests at 140 locations scattered across the country. In total, the researchers were able to track changes in the abundance of more than 1.8 thousand species of forest beetles, including about three hundred species of herbivorous arthropods, as well as about five hundred species of fungus-eating, omnivorous and carnivorous invertebrates. In addition, the scientists studied how forest areas, species diversity of trees and other plants, biomass and deadwood volume, as well as other parameters changed.
The analysis showed that the number of forest beetles has been declining rapidly over the past decade. These adverse changes affected populations of more than 60% of the arthropod species studied, with fungus-eating and carnivorous insect species suffering the most.
The largest decrease in population size was in insects, which were or were large in most of the European forests studied. The number of insects fell particularly strongly in forests with a high proportion of coniferous trees, including various species of pine and spruce.
The study’s authors do not have a definitive answer as to what exactly the identified trend is linked to, but it is likely that people and their economic activities are responsible for such a decline in numbers. This hypothesis is supported by the fact that species decline is felt much less in protected areas.
previous work showedmice tend to fall into the conjunction logical fallacy.