Insect populations have declined hugely in all parts of the world where multi-decade studies have been carried out. In Germany, over 27 years of annual measurements, flying insect populations decreased by 75% (https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0185809). Here in central North Carolina, there have been no quantitative studies, but butterflies and moths and night-flying beetles and dragonflies have simply disappeared. And the nighttime drone of insects is nowhere near as loud as just a few years ago. The consequences will be disasterous.
July 31, 2013