Individual study: Conservation headlands: effects on butterfly distribution and behaviour
Dover J.W. (1997) Conservation headlands: effects on butterfly distribution and behaviour. Agriculture, Ecosystems & Environment, 63, 31-49
This study is summarised as evidence for the intervention(s) shown on the right. The icon shows which synopsis it is relevant to.
Leave headlands in fields unsprayed (conservation headlands)
A replicated, controlled, paired study in 1985-1987 of butterfly (Lepidoptera) behaviour in headlands of 14 cereal fields in north-east Hampshire (Dover 1997) found that flight speeds tended to be slower and more time was spent resting, interacting and foraging in conservation headlands (no broadleaved herbicides) than those with conventional herbicide applications. Flight and transit speeds of male Pieridae and transits of female green-veined white Pieris napi were significantly slower in conservation headlands. In contrast gatekeeper Pyronia tithonus males (in 1986) were significantly slower in the sprayed headlands, sample sizes were too small for other species. In fields with sprayed headlands, spring emerging large white P. brassicae, green-veined white and small white P. rapae were principally associated with the hedgerow, whilst in fields with conservation headlands they were associated with the headlands. In sprayed headlands, the principal activity was flight, whereas in conservation headlands there was an increase in time spent resting, interacting and particularly foraging. Butterflies that emerged in the summer tended to have less of an association with conservation headlands than spring-emerging butterflies. Limited data were available for meadow brown Maniola jurtina and gatekeeper. Half of the 14 fields were sprayed with conventional pesticides and the other half had conservation headlands. The behaviour and location (hedgerow or headland) of five species of butterfly were observed during the middle of the day along 4-8 headlands. This study was part of the same experimental set-up as (Rands et al. 1984, Rands 1985, Rands 1986, Rands & Sotherton 1986, Dover et al. 1990, Sotherton 1991).