Insects decline in Germany

This video says about itself:

5 September 2017

Due to a reduction in biodiversity, insect populations have declined in Europe by as much as 80%. Educators in South Africa predict the same fate for their country.

From PLOS one:

More than 75 percent decline over 27 years in total flying insect biomass in protected areas

Published: October 18, 2017

Abstract

Global declines in insects have sparked wide interest among scientists, politicians, and the general public. Loss of insect diversity and abundance is expected to provoke cascading effects on food webs and to jeopardize ecosystem services. Our understanding of the extent and underlying causes of this decline is based on the abundance of single species or taxonomic groups only, rather than changes in insect biomass which is more relevant for ecological functioning.

Here, we used a standardized protocol to measure total insect biomass using Malaise traps, deployed over 27 years in 63 nature protection areas in Germany (96 unique location-year combinations) to infer on the status and trend of local entomofauna.

Our analysis estimates a seasonal decline of 76%, and mid-summer decline of 82% in flying insect biomass over the 27 years of study. We show that this decline is apparent regardless of habitat type, while changes in weather, land use, and habitat characteristics cannot explain this overall decline. This yet unrecognized loss of insect biomass must be taken into account in evaluating declines in abundance of species depending on insects as a food source, and ecosystem functioning in the European landscape.

La Trobe University researchers have uncovered an exception to the global phenomenon known as ‘Insect Armageddon’ in the largest study of Australian insect populations conducted to date. Researchers studied ants in the Simpson Desert for 22 years and found that local changes in climate, such as long-term increases in rainfall, combined with human efforts to restore ecosystems, may have led to increased numbers of species — rather than the declines which might be expected in such unpredictable conditions: here.