Scientists shocked by 75 percent decline in flying insect numbers

A malaise trap in a nature protection area in Germany. Credit Hallmann et

"However", he continued, "when you get an over 75 percent decline in total insect biomass, you know this is not due to a few or vulnerable species".

Although scientists were previously aware of the decline in specific populations, such as European grassland butterflies, the recent study demonstrates that the scale of the problem is much larger and of greater concern. A decline in their numbers has the potential to cause huge disruption to the food chain-the valued of the "ecosystem services" provided by wild insects is estimated to be $57 billion annually in the USA alone.

Germany is witnessing a dramatic decline in native insect populations which endangers the survival of entire ecosystems, a study published on Thursday warned.

Hans de Kroon, project leader at Radboud University, said: "The fact that flying insects are decreasing at..."

Caspar Hallmann, a member of the research team at Radboud, described the figures as "very alarming". According to the results, there is a 76 percent decline and mid-summer 82 percent decline in flying insect biomass in the 27 years researchers conducted the study.

While no corresponding data over the same study period is available for non-flying insects, "we can just hope they are faring better, but we have no reason to believe that is the case", Hallman said.

"We don't often think about insects other than 'eww, an insect.' But these are the organisms running the world".

Incidentally, most of the 63 nature reserves in the study are surrounded by agricultural lands, meaning pesticide use may be to blame.

While no single cause was identified, the widespread destruction of wild areas for agriculture and the use of pesticides are considered likely factors.

Insects, she says, are "crucial" to biodiversity, and "we exist because of biodiversity". Comparing the mass and the number of individuals in such a "catch", it is possible to understand how changing species diversity and abundance of insects over time. Pollination of both crops and wild plants are also affected, as is nutrient cycling in the soil.

The researchers were alarmed by their findings since insects are important pollinators and provide food for larger animals such as birds and other creatures. "We've probably only identified only 10% of insects and some are going extinct before we can even name them".

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