I hesitated before reading Oliver Milman's The Insect Crisis: The Fall of the Tiny Empires that Run the World. I knew it would be depressing. I made myself read it anyway because it's important not to look away. I was right, it was a depressing read. There are multiple strands of evidence that the past few decades have seen substantial, sometimes dramatic, falls in insect populations around the world. Various longitudinal surveys in different places - primarily Europe and the USA - show declines in insect numbers that are generally in the range of 20-50% but in some places are as much as 90%. Some formerly abundant species, like North America's Monarch Butterflies or some species of European and North American bumblebees, are now threatened, but even species that are far from being threatened, like our common domesticated honeybees, are facing increasing pressure. A caveat is in order. None of these are comprehensive region-wide studies, ...
'Contemplating the teeming life of the shore, we have an uneasy sense of the communication of some universal truth that lies just beyond our grasp.' - Rachel Carson