Reduced pesticide inputs on cereal field margins: the effects on butterfly abundance

Published source details Dover J., Sotherton N. & Gobbett K.A.Y. (1990) Reduced pesticide inputs on cereal field margins: the effects on butterfly abundance. Ecological Entomology, 15, 17-24.
Share Tweet Email

Actions

This study is summarised as evidence for the following.

	Action	Category
	Leave headlands in fields unsprayed (conservation headlands) Action Link
	Leave headlands in fields unsprayed (conservation headlands) Action Link

Leave headlands in fields unsprayed (conservation headlands)

A replicated, paired, controlled study in 1984–1987 on an arable farm in Hampshire, UK (Dover et al. 1990, same experimental set up as Dover 1997), found that the abundance and species richness of butterflies was greater on unsprayed conservation headlands than on conventional sprayed headlands. On unsprayed headlands, the abundance of butterflies (222–472 individuals/km) was higher than on conventional headlands (80–259 individuals/km) in all four years. In total, 29 species of butterfly were recorded, of which 13–21 were found on unsprayed headlands and 13–17 on conventional headlands each year (statistical significance not assessed). On half of 14 fields, a 6-m strip around the edge (headland) was left unsprayed, while the remainder received conventional broadleaved herbicide applications. Spring and summer applications of insecticide were not used anywhere on the farm. From 1984–1987, butterflies were sampled along a transect at least once a week from 14 May to 19 August. Sprayed and unsprayed headlands were paired with similar adjacent habitats.

(Summarised by: Andrew Bladon, edited from Farmland synopsis)
Leave headlands in fields unsprayed (conservation headlands)

A continuation of the same replicated, controlled, paired study as in (Rands & Sotherton 1986) in Hampshire, UK, (Dover et al. 1990), found that butterfly (Lepidoptera) abundance was greater on conservation headlands than on conventional headlands over a further three years (1985-1987). Between 1984 and 1987, 29 species of butterfly were recorded, of which 13-21 were on conservation and 13-17 on conventional headlands each year. Significantly more individuals were found on conservation headlands (222-472/km) than on conventional headlands (80-259/km) in all years. This study was part of the same experimental set-up as (Rands et al. 1984, Rands 1985, Rands 1986, Rands & Sotherton 1986, Sotherton 1991, Dover 1997).