Insectivorous birds consume an estimated 400–500 million tons of prey annually

In this paper, we present an estimate of the predation impact of the global population of insectivorous birds based on 103 (for the most part) published studies of prey consumption (kg ha-1 season-1) of insectivorous birds in seven biome types. By extrapolation-taking into account the global land cover of the various biomes-an estimate of the annual prey consumption of the world's insectivorous birds was obtained. We estimate the prey biomass...