Manage vineyards to benefit butterflies and moths
Overall effectiveness category Awaiting assessment
Number of studies: 2
Background information and definitions
As perennial crops, vineyards form large areas of consistent agricultural habitat across Mediterranean-type landscapes. Like other perennial crops, this creates opportunities to manage vineyards as complete ecosystems, by providing the resources which butterflies and moths need within the crop. This could include encouraging native plant species to grow around the vines, altering the timing or frequency of management such as pruning and tillage, or reducing the application of chemicals to the vines or surrounding habitat.
For studies which test reductions in chemical application alone, see “Threat: Pollution”.
Supporting evidence from individual studies
A replicated, paired, site comparison study in 2012–2013 in eight vineyards in Washington State, USA (James et al. 2015) found that vineyards which were managed to encourage native plants had a higher abundance, but not species richness, of butterflies than conventionally managed vineyards. Butterfly abundance was higher in habitat-enhanced vineyards (20 individuals/visit) than in conventionally managed vineyards (6 individuals/visit). Butterfly species richness was not significantly higher in enhanced vineyards (5.6 species/visit) than conventional vineyards (2.8 species/visit), although a total of 29 species were recorded in enhanced vineyards compared to nine in conventional vineyards over the two years. Four pairs of vineyards (0.5–32 km apart) were selected. In each pair, one “habitat-enhanced” vineyard had native plants restored at the site for five years (2 sites) or 15–20 years (2 sites), and insecticides were never, or rarely, used. The four “conventional” vineyards did not encourage native plants, frequently applied herbicides and occasionally sprayed pesticides. From May–September 2012–2013, butterflies were surveyed for 30–40 minutes every two weeks in each vineyard.Study and other actions tested
A replicated, site comparison study in 2013–2014 in 20 vineyards in Catalonia, Spain (Puig-Montserrat et al. 2017) found that grass strips between the crop lines had more butterfly species than the crop lines themselves. There were more species of butterfly along grass strips in vineyards (32–33 species) than along the crop lines (22–30 species). In addition, vineyards managed with fewer chemicals had more butterfly species (30–33 species) than conventionally managed vineyards (22–32 species). Twenty vineyards managed with uncultivated grass strips between the crop lines were surveyed. Ten vineyards were managed with fewer insecticide and herbicide (Glyphosate) applications/year than 10 conventionally managed vineyards. From April–August 2013–2014, butterflies were surveyed four times/year on two 100-m transects/vineyard in nine vineyards/year. One transect was along crop lines, and the other was along grass strips between crop lines.Study and other actions tested