The effects of field margin restoration on the meadow brown butterfly (Maniola jurtina)

Restrict certain pesticides or other agricultural chemicals

A replicated, randomized, site comparison study in 1989–1991 in Oxfordshire, UK (Feber et al. 1994, same experimental set-up as Feber et al. 1996) found more adult meadow brown Maniola jurtina on naturally regenerated field margins that were not sprayed with herbicide than on margins which were sprayed once a year. After 1–2 years of herbicide application, there were more adult meadow brown on cut or uncut margins which were not sprayed (4–10 individuals/50 m) than on uncut sprayed margins (3–4 individuals/50 m). In the first year of herbicide application, there was no difference between unsprayed (7–15 individuals/50 m) and sprayed margins (15 individuals/50 m). In October 1987, two-metre-wide field margins around arable fields were rotovated and left to naturally regenerate. Fifty-metre-long plots were either uncut and unsprayed, subject to one of four different cutting regimes but unsprayed, or uncut but sprayed once/year with herbicide (glyphosate, 3 l/ha Roundup^TM in 175 l water) in late June or early July 1989–1991. There were eight replicates of each treatment. From June–September 1989, and April–September 1990–1991, adult meadow brown were monitored weekly.

(Summarised by: Andrew Bladon, edited from Farmland synopsis)

Plant nectar flower mixture/wildflower strips

A replicated, randomized, site comparison study in 1987–1991 in Oxfordshire, UK (Feber et al. 1994, same experimental set-up as Feber & Smith 1995, Feber et al. 1996) found that field margins sown with wildflower seed mix had more adult meadow brown Maniola jurtina than unsown margins, and that margin management affected butterfly numbers. More adult meadow browns were found on margins sown with wildflowers (4–52 butterflies/50 m) than on unsown margins (4–15 butterflies/50 m). Sown margins also had more butterflies if they were left uncut (13–39 butterflies/50 m), or were cut in spring and autumn (16–52 butterflies/50 m), than if they were cut in summer (4–22 butterflies/50 m). There was no difference in the abundance of meadow brown caterpillars between sown and unsown, or cut and uncut, plots (3 caterpillars/plot). There were more meadow browns on all the experimental field margins than on narrow, unmanaged field boundaries of a neighbouring farm (numbers not given). In October 1987, two-metre-wide field margins around arable fields were rotovated, and either sown with a wildflower seed mix in March 1988 or left to regenerate naturally. Within each sown and unsown margin, 50-m-long plots were managed in one of four ways, with eight replicates of each treatment: uncut; cut once in June; cut April and June; cut in April and September. Hay was collected after cutting. From June–September 1989, and April–September 1990–1991, adult meadow brown were monitored weekly. In spring 1991, meadow brown caterpillars were sampled by sweep netting and visual searching.

(Summarised by: Andrew Bladon, edited from Farmland synopsis)

Create uncultivated margins around intensive arable or pasture fields

A replicated, randomized, site comparison study in 1987–1991 in Oxfordshire, UK (Feber et al. 1994, same experimental set-up as Feber & Smith 1995, Feber et al. 1996) found that unsown field margins had fewer adult meadow brown Maniola jurtina than margins sown with wild grasses and non-woody broadleaved plants (forbs), and that margin management affected butterfly numbers. Fewer adult meadow browns were found on unsown, naturally regenerating margins (4–15 butterflies/50 m) than on sown margins (4–52 butterflies/50 m). However, unsown margins had more butterflies if they were left uncut (4–13 butterflies/50 m), or were cut in spring and autumn (7–15 butterflies/50 m), than if they were cut in summer (4–10 butterflies/50 m). There was no difference in the abundance of meadow brown caterpillars between unsown and sown, or uncut and cut, plots (3 caterpillars/plot). There were more meadow browns on all the experimental field margins than on narrow, unmanaged field boundaries of a neighbouring farm (numbers not given). In October 1987, two-metre-wide field margins around arable fields were rotovated, and either left to regenerate naturally or sown with a wildflower seed mix in March 1988. Within each unsown and sown margin, 50-m-long plots were managed in one of four ways, with eight replicates of each treatment: uncut; cut once in June; cut April and June; cut in April and September. Hay was collected after cutting. From June–September 1989, and April–September 1990–1991,  meadow brown adults were monitored weekly. In spring 1991, meadow brown caterpillars were sampled by sweep netting and visual searching.

(Summarised by: Andrew Bladon, edited from Farmland synopsis)

Create uncultivated margins around intensive arable or pasture fields

A randomized, replicated trial from 1987 to 1991 in Oxfordshire, UK (Feber et al. 1994) found more adult meadow brown butterflies Maniola jurtina on 2 m-wide naturally regenerated field margins left uncut, or cut in spring or autumn than on margins cut in summer (4-10 meadow browns/50 m with summer cut, 4-15 meadow browns/50 m without). Unsown margins had 4-10 meadow browns/50 m in 1991 and 1992, fewer than margins sown with a wildflower mix (4-52 meadow browns/50 m). There was no difference between treatments in abundance of meadow brown larvae (3 larvae/plot on average). There were more meadow browns on all the experimental field margins than on narrow, unmanaged field boundaries of a neighbouring farm (numbers not given). Two metre-wide field margins were established around arable fields in October 1987. They were either left to naturally regenerate or sown with a wildflower seed mix in March 1988. Both treatments were rotavated before sowing. Fifty metre-long plots were managed in one of the following ways: uncut; cut once in June hay collected; cut April and June hay collected; cut in April and September hay collected; cut April and June hay left lying (unsown margins only); sprayed once a year in summer (unsown margins only). There were six replicates of each treatment. Adult meadow brown butterflies were monitored weekly along walked transects in the experimental plots from June to September 1989 and from April to September 1990 and 1991. Meadow brown larvae were sampled in spring 1991 by sweep netting and visual searching. This study was part of the same experimental set-up as Feber et al.1996, Baines et al. 1998, Bell et al. 1999, Haughton et al. 1999, Smith et al. 2010).

Plant nectar flower mixture/wildflower strips

A randomized, replicated trial from 1987 to 1991 in Oxfordshire, UK (Feber et al. 1994) found that field margins sown with wildflower seed mix had more adult meadow brown butterflies Maniola jurtina but not more larvae than unsown margins in two of the three study years. In 1990 and 1991, sown plots had 4-52 meadow browns/50 m, and unsown plots 4-10 meadow browns/50 m. In all three years, there were more meadow brown butterflies on uncut margins, or margins cut in spring or autumn than in margins cut in summer (sown margins: 4-22 meadow browns/50 m with summer cut, 14-52 meadow browns/50 m without summer cut). There was no difference in the abundance of meadow brown larvae (three larvae/plot on average) between treatments. Two-metre-wide field margins were established around arable fields in October 1987. In 1988 margins were either left to naturally regenerate or sown with a wildflower seed mix (17 wildflower species, six grass species, with a wildflower:grass weight ratio of 1:4). Both treatments were rotavated before sowing. Fifty-metre-long plots were managed in one of the following ways: uncut, cut once in June with hay collected, cut April and June with hay collected, cut in April and September with hay collected, cut April and June with hay left lying (unsown margins only) or sprayed once a year in summer (unsown margins only). There were six replicates of each treatment. Adult meadow brown butterflies were monitored weekly along walked transects in the experimental plots from June to September 1989 and from April to September 1990 and 1991. Meadow brown larvae were sampled in spring 1991, by sweep netting and visual searching. This study is part of the same experimental set-up as Feber et al. 1996, Baines et al. 1998, Bell et al. 1999, Haughton et al. 1999, Smith et al. 1999, Bell et al. 2002, Smith et al. 2010.

Reduce fertilizer, pesticide or herbicide use generally

A randomized, replicated trial from 1987 to 1991 on the Oxford University Farm, Wytham, Oxfordshire, UK (Feber et al. 1994) found fewer adult meadow brown butterflies Maniola jurtina on 2 m-wide naturally regenerated field margins that were sprayed with herbicide once in summer, compared to any margins that were not sprayed. There were 3-4 meadow browns/50 m sprayed plot on average, compared to 4-13 meadow browns/50 m on unsown, uncut margins that were not sprayed. There was no difference between treatments in abundance of meadow brown larvae (3 larvae/plot on average). Two metre-wide field margins were established around arable fields in October 1987, rotavated and left to naturally regenerate from March 1988. Fifty metre-long plots were either uncut and unsprayed, subject to one of four different cutting regimes but unsprayed, uncut but sprayed once a year with herbicide (glyphosate) in late June or July. There were six replicates of each treatment. Adult meadow brown butterflies Maniola jurtina were monitored weekly along walked transects in the experimental plots from June to September 1989 and from April to September 1990 and 1991. Meadow brown larvae were sampled in spring 1991, by sweep netting and visual searching.