Title: Mass Seasonal Migrations of Hoverflies Provide Extensive Pollination and Crop Protection Services
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The long-range migrations redistribute tons of essential nutrients (nitrogen [N] and phosphorus [P]) and transport billions of pollen grains between Britain and Europe, and locally produced populations consume 6 trillion aphids and make billions of flower visits. Migrant hoverfly abundance fluctuated greatly between years, but there was no evidence of a population trend during the 10-year study period. Considering that many beneficial insects are seriously declining [7Biesmeijer J.C. Roberts S.P.M. Reemer M. Ohlemüller R. Edwards M. Peeters T. Schaffers A.P. Potts S.G. Kleukers R. Thomas C.D. et al.Parallel declines in pollinators and insect-pollinated plants in Britain and the Netherlands.Science. 2006; 313: 351-354Crossref PubMed Scopus (2028) Google Scholar, 10Powney G.D. Carvell C. Edwards M. Morris R.K.A. Roy H.E. Woodcock B.A. Isaac N.J.B. Widespread losses of pollinating insects in Britain.Nat. Commun. 2019; 10: 1018Crossref PubMed Scopus (303) Google Scholar, 13Brooks D.R. 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