德国63个自然保护区内的飞行类昆虫数量在过去27年中减少了四分之三以上。研究人员认为这一现象值得警惕，因为飞虫是自然生态系统中的重要组成部分。它既是植物的授粉者，也是扮演食物链的关键角色。

Since 1989, scientists have been monitoring flying insect populations in 63 nature reserves across Germany. The decline of some species, like butterflies, has long been suspected but this research included lesser studied insects, like wasps, flies and moths. The drop in numbers of more than three quarters over 27 years turned out to be more severe than previously thought.

The insects play a vital role in pollination and as a food source for birds. No one factor alone could explain their disappearance, but researchers said modern agriculture creates a hostile environment - a desert for insects.

While, anecdotally, in recent years, drivers have reported fewer insects being squashed on their windscreens - another signal with the decline in bugs across all landscapes, experts said.