Part Two / How our Planet is Changing

2.20 Insects

All online sources accessed on

  1. UK butterfly populations have fallen by about 50 per cent since 1976 Warren, M. S., et al., ‘The decline of butterflies in Europe: problems, significance, and possible solutions’, Proceedings of the National Academy of Sciences, 118 (2), 2021: Article e2002551117, https://doi.org/10.1073/pnas.2002551117.

    The biomass of flying insects on German nature reserves Hallmann, C. A., et al., ‘More than 75 percent decline over 27 years in total flying insect biomass in protected areas’, PLOS One, 12 (10), 2017: Article e0185809, https://doi.org/10.1371/journal.pone.0185809.

    caddis flies declined by 60 per cent between 2006 and 2017 Ibid.

    In North America, numbers of the monarch butterfly Center for Biological Diversity, ‘Eastern monarch butterfly population falls again’, https://biologicaldiversity.org/w/news/press-releases/eastern-monarch-butterfly-population-falls-again-2021-02-25/, 25 February 2021.

  2. Attempts to calculate an average rate of decline Wagner, D. L., et al., ‘Insect decline in the Anthropocene: death by a thousand cuts’, , Proceedings of the National Academy of Sciences, 118 (2), 2021: Article e2023989118, https://www.pnas.org/content/118/2/e2023989118/.

  3. cinnabar moths … declined in number by 83 per cent Fox, R., et al., The State of Britain’s Larger Moths, Butterfly Conservation and Rothamsted Research, 2006, https://doi.org/10.23637/rothamsted.898z8.