Bee losses followed World Wars

Between 1851 and 1986, withering wildflower populations and booming agriculture may have joined forces to knock down the number of pollinators buzzing in Britain. Using inordinately detailed records collected mainly by amateur naturalists, researchers found that 19 species of bees and flower-visiting wasps died out in that time span, leaving about 500 pollinator species standing. Scientists suspect that at least four other species have since gone extinct, but it’s too soon to tally the losses.

Amid the century-long decline, the late 1920s through the late 1950s was an especially deadly period for Britain’s pollinators. The era corresponds to agricultural innovations such as synthetic fertilizers and land use changes that trailed the two world wars. The findings appear in the Dec. 12 Science.