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Providing evidence to improve practice

Action: Plant more than one crop per field (intercropping) Bird Conservation

Key messages

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A study from the USA found that 35 species of bird used fields with intercropping, with four nesting, but that productivity from the fields was very low.


Supporting evidence from individual studies


A study on two arable farms in Iowa, USA, in May-August 1992-3 (Stallman & Best 1996), found that 35 bird species used fields under an experimental intercropping system, with an average of 108 birds/count/100 ha. Three native species (red-winged blackbird Agelaius phoeniceus, common grackle Quiscalus quiscula and vesper sparrow Pooecetes gramineus) nested in the fields, but that only one nest of forty (2.5%) successfully fledged young. Destruction by farming activities was the largest cause of nest mortality (39%) followed by predation (29%). Desertion only occurred at 5% of nests. Strips were 4.6 m wide and contained corn, soybeans and oats as well as mammoth red clover Trifolium pratense.


Referenced papers

Please cite as:

Williams, D.R., Child, M.F., Dicks, L.V., Ockendon, N., Pople, R.G., Showler, D.A., Walsh, J.C., zu Ermgassen, E.K.H.J. & Sutherland, W.J. (2019) Bird Conservation. Pages 141-290 in: W.J. Sutherland, L.V. Dicks, N. Ockendon, S.O. Petrovan & R.K. Smith (eds) What Works in Conservation 2019. Open Book Publishers, Cambridge, UK.