Deteriorating insect population
Habitat destruction, nicotinamide insecticides
https://en.wikipedia.org/wiki/Decline_in_insect_populations
Several studies report what appears to be a substantial decline in insect populations. Some of the insects most affected include bees, butterflies, moths, beetles, dragonflies and damselflies. Anecdotal evidence has been offered of much greater apparent abundance of insects in the 20th century; recollections of the windscreen phenomenon are an example