Insect populations are in decline as a result of a number of man-made stresses including habitat loss, chronic exposure to complex mixtures of pesticides, the spread of non-native insect diseases within commercial bee nests, and the beginnings of the impacts of climate change [Goulson et al. 2015]. The disease issue primarily affects only bees, but the others are problems that all insects face.
Without insects a multitude of birds, bats, reptiles, amphibians, small mammals and ﬁsh would disappear, for they would have nothing to eat. Eighty-seven percent of all plant species require animal pollination, most of it delivered by insects [Ollerton et al. 2011]. That is pretty much all of them aside from the grasses and conifers. Approximately three-quarters of all crop types grown by humans require pollination by insects, a service estimated to be worth between $235 billion and $577 billion per year worldwide [Lautenbach et al. 2012].
Financial aspects aside, we could not feed the global human population without pollinators. Insects provide a multitude of ecosystem services to us including pollination, nutrient recycling , decomposition, pest control and food for other species.
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