With almost one million described species, insects eclipse all other forms of animal life on Earth, not only in sheer numbers, diversity, and biomass, but also in their importance to functioning ecosystems. However, human-induced changes to the natural environment threaten vast numbers of these organisms and the vital services they provide to ecosystems. Leading causes of insect endangerment are habitat destruction or alteration of habitat by chemical pollutants (such as pesticides). Pesticides are implicated in the decline of many native bees and some aquatic insects.
Read the article: S Hoffman Black, DM Vaughan. In : The Encyclopedia of Insects, Academic Press, San Diego, CA.
Aquatic insect diversity is subject to a broad spectrum of threats, including chemical pollution of waters from industry and agriculture. Adequate legislation exists in the United States and Europe to provide protection to aquatic insect taxa at risk, but the implementation of this legislation is often hampered by a lack of taxonomic and distributional knowledge, and by a concentration of recovery efforts on more highly visible vertebrate taxa.
Bron: DA Polhemus, American Zoologist (1993) 33:588-598