Pollinator decline

A dead carpenter bee

Pollinator decline is the reduction in abundance of insect and other animal pollinators in many ecosystems worldwide that began being recorded at the end of the 20th century. Multiple lines of evidence exist for the reduction of wild pollinator populations at the regional level, especially within Europe and North America.[1][2][3][4] Similar findings from studies in South America, China and Japan make it reasonable to suggest that declines are occurring around the globe.[5][6][7][8] The majority of studies focus on bees, particularly honeybee and bumblebee species, with a smaller number involving hoverflies and lepidopterans.[9][1][10][11][12]

The picture for domesticated pollinator species is less clear. Although the number of managed honey bee colonies in Europe and North America declined by 25% and 59% between 1985-2005 and 1947-2005 respectively, overall global stocks increased due to major hive number increases in countries such as China and Argentina.[13][14][15] Nevertheless, in the time managed honeybee hives increased by 45% demand for animal pollinated crops tripled, highlighting the danger of relying on domesticated populations for pollination services.[15]

Pollinators participate in the sexual reproduction of many plants by ensuring cross-pollination, essential for some species and a major factor in ensuring genetic diversity for others. Since plants are the primary food source for animals, the possible reduction or disappearance of pollinators has been referred to as an "armageddon" by some journalists.

  1. ^ a b Powney, Gary D.; Carvell, Claire; Edwards, Mike; Morris, Roger K. A.; Roy, Helen E.; Woodcock, Ben A.; Isaac, Nick J. B. (26 March 2019). "Widespread losses of pollinating insects in Britain". Nature Communications. 10 (1): 1018. Bibcode:2019NatCo..10.1018P. doi:10.1038/s41467-019-08974-9. PMC 6435717. PMID 30914632. S2CID 85528078.
  2. ^ Soroye, Peter; Newbold, Tim; Kerr, Jeremy (7 February 2020). "Climate change contributes to widespread declines among bumble bees across continents". Science. 367 (6478): 685–688. Bibcode:2020Sci...367..685S. doi:10.1126/science.aax8591. PMID 32029628. S2CID 211049610.
  3. ^ Goulson, D.; Nicholls, E.; Botias, C.; Rotheray, E. L. (27 March 2015). "Bee declines driven by combined stress from parasites, pesticides, and lack of flowers". Science. 347 (6229): 1255957. doi:10.1126/science.1255957. PMID 25721506. S2CID 206558985.
  4. ^ Potts, Simon G.; Biesmeijer, Jacobus C.; Kremen, Claire; Neumann, Peter; Schweiger, Oliver; Kunin, William E. (June 2010). "Global pollinator declines: trends, impacts and drivers". Trends in Ecology & Evolution. 25 (6): 345–353. Bibcode:2010TEcoE..25..345P. doi:10.1016/j.tree.2010.01.007. PMID 20188434.
  5. ^ Schmid-Hempel, Regula; Eckhardt, Michael; Goulson, David; Heinzmann, Daniel; Lange, Carlos; Plischuk, Santiago; Escudero, Luisa R.; Salathé, Rahel; Scriven, Jessica J.; Schmid-Hempel, Paul (July 2014). "The invasion of southern South America by imported bumblebees and associated parasites". Journal of Animal Ecology. 83 (4): 823–837. Bibcode:2014JAnEc..83..823S. doi:10.1111/1365-2656.12185. PMID 24256429.
  6. ^ Xie, Zhenghua; Williams, Paul H.; Tang, Ya (1 December 2008). "The effect of grazing on bumblebees in the high rangelands of the eastern Tibetan Plateau of Sichuan". Journal of Insect Conservation. 12 (6): 695–703. Bibcode:2008JICon..12..695X. doi:10.1007/s10841-008-9180-3. S2CID 19979709.
  7. ^ Williams, Paul; Tang, Ya; Yao, Jian; Cameron, Sydney (1 June 2009). "The bumblebees of Sichuan (Hymenoptera: Apidae, Bombini)". Systematics and Biodiversity. 7 (2): 101–189. Bibcode:2009SyBio...7..101W. doi:10.1017/S1477200008002843. S2CID 86166557.
  8. ^ Inoue, Maki N.; Yokoyama, Jun; Washitani, Izumi (1 April 2008). "Displacement of Japanese native bumblebees by the recently introduced Bombus terrestris (L.) (Hymenoptera: Apidae)". Journal of Insect Conservation. 12 (2): 135–146. Bibcode:2008JICon..12..135I. doi:10.1007/s10841-007-9071-z. S2CID 33992235.
  9. ^ Biesmeijer, J. C. (21 July 2006). "Parallel Declines in Pollinators and Insect-Pollinated Plants in Britain and the Netherlands". Science. 313 (5785): 351–354. Bibcode:2006Sci...313..351B. doi:10.1126/science.1127863. PMID 16857940. S2CID 16273738.
  10. ^ Fox, Richard; Oliver, Tom H.; Harrower, Colin; Parsons, Mark S.; Thomas, Chris D.; Roy, David B. (August 2014). "Long-term changes to the frequency of occurrence of British moths are consistent with opposing and synergistic effects of climate and land-use changes". Journal of Applied Ecology. 51 (4): 949–957. Bibcode:2014JApEc..51..949F. doi:10.1111/1365-2664.12256. PMC 4413814. PMID 25954052.
  11. ^ Forister, Matthew L.; Jahner, Joshua P.; Casner, Kayce L.; Wilson, Joseph S.; Shapiro, Arthur M. (2011). "The race is not to the swift: Long-term data reveal pervasive declines in California's low-elevation butterfly fauna". Ecology. 92 (12): 2222–2235. Bibcode:2011Ecol...92.2222F. doi:10.1890/11-0382.1. PMID 22352162.
  12. ^ Semmens, Brice X.; Semmens, Darius J.; Thogmartin, Wayne E.; Wiederholt, Ruscena; López-Hoffman, Laura; Diffendorfer, Jay E.; Pleasants, John M.; Oberhauser, Karen S.; Taylor, Orley R. (September 2016). "Quasi-extinction risk and population targets for the Eastern, migratory population of monarch butterflies (Danaus plexippus)". Scientific Reports. 6: 23265. Bibcode:2016NatSR...623265S. doi:10.1038/srep23265. PMC 4800428. PMID 26997124.
  13. ^ Potts, Simon G.; Roberts, Stuart P. M.; Dean, Robin; Marris, Gay; Brown, Mike A.; Jones, Richard; Neumann, Peter; Settele, Josef (1 January 2010). "Declines of managed honey bees and beekeepers in Europe". Journal of Apicultural Research. 49 (1): 15–22. Bibcode:2010JApiR..49...15P. doi:10.3896/IBRA.1.49.1.02. S2CID 67794397.
  14. ^ vanEngelsdorp, Dennis; Hayes, Jerry Jr.; Underwood, Robyn M.; Pettis, Jeffery (30 December 2008). "A Survey of Honey Bee Colony Losses in the U.S., Fall 2007 to Spring 2008". PLOS ONE. 3 (12): e4071. Bibcode:2008PLoSO...3.4071V. doi:10.1371/journal.pone.0004071. PMC 2606032. PMID 19115015.
  15. ^ a b Aizen, Marcelo A.; Harder, Lawrence D. (June 2009). "The Global Stock of Domesticated Honey Bees Is Growing Slower Than Agricultural Demand for Pollination". Current Biology. 19 (11): 915–918. Bibcode:2009CBio...19..915A. doi:10.1016/j.cub.2009.03.071. PMID 19427214. S2CID 12353259.