Assessing the value of Rural Stewardship schemes for providing forage resources and nesting habitat for bumblebee queens (Hymenoptera: Apidae)
Published source details Lye G., Park K., Osborne J., Holland J. & Goulson D. (2009) Assessing the value of Rural Stewardship schemes for providing forage resources and nesting habitat for bumblebee queens (Hymenoptera: Apidae). Biological Conservation, 142, 2023-2032.
Actions
This study is summarised as evidence for the following.
| Action | Category | |
|---|---|---|
Increase areas of rough grassland for bumblebee nesting Action Link |  | |
Manage hedges to benefit bees Action Link | | |
Restore species-rich grassland vegetation Action Link | | |
Introduce agri-environment schemes to benefit wild bees Action Link | | |
Manage hedgerows to benefit wildlife (includes no spray, gap-filling and laying) Action Link |  | |
Pay farmers to cover the cost of conservation measures (as in agri-environment schemes) Action Link | | |
Plant grass buffer strips/margins around arable or pasture fields Action Link | | |
Restore/create species-rich, semi-natural grassland Action Link | |
Increase areas of rough grassland for bumblebee nesting
A replicated, controlled trial of the Rural Stewardship agri-environment scheme on 10 farms in Scotland found that 1.5 to 6 m wide grassy field margins attracted nest-searching queen bumblebees at higher densities than managed or unmanaged grasslands or hedgerows (Lye et al. 2009). On five farms with the agri-environment scheme, researchers counted an average of around nine nest-searching queens/100 m on grassy field margins, compared to around seven nest-searching queens/100 m in species-rich grassland transects, five for conventional arable field margins, and four on unmanaged (abandoned) grassland transects. The study did not record the numbers of established nests later in the year.
Manage hedges to benefit bees
A replicated, controlled trial of the Rural Stewardship agri-environment scheme on five farms in Scotland found that hedgerows dominated by hawthorn Crataegus monogyna or blackthorn Prunus spinosa were less attractive than field margins or grasslands to nest-searching queen bumblebees Bombus spp. in April and May (Lye et al. 2009). There was no significant difference in numbers of foraging or nesting queens between hedgerows managed under the agri-environment scheme (winter cut every three years, gaps filled, vegetation below unmown and unsprayed) and conventionally managed hedgerows. The study took place before the woody species comprising the hedgerow came into flower.
Restore species-rich grassland vegetation
A replicated, controlled trial of the species-rich grassland management or restoration option under the Rural Stewardship agri-environment scheme in Scotland (Rural Stewardship Scheme, RSS) found that RSS species-rich grassland attracted more nest-searching queen bumblebees Bombus spp. but fewer foraging queens than areas of naturally regenerated, largely unmanaged grasslands (Lye et al. 2009). Five RSS farms were paired with five conventional farms. Across all farms, unmanaged grassland on conventional farms attracted the highest abundance of foraging queen bumblebees (over 4 queens/100 m transect, compared to less than 3 foraging queens/100 m transect on species-rich grassland), also in comparison with hedgerow and field margin transects. Unmanaged grassland transects had more nectar and pollen-providing flowers than species-rich grassland in April and May, when queen bumblebees are on the wing.
Introduce agri-environment schemes to benefit wild bees
In a replicated controlled trial involving 10 farms in east and central Scotland, Lye et al. (2009) compared numbers of nest-searching and foraging queen bumblebees Bombus spp. on land that had been managed under three different options of the Rural Stewardship Scheme (unsprayed grassy field margins, species-rich grassland and hedgerows) for three years with conventionally managed land of the same type. On farms with the agri-environment scheme, transects under the scheme attracted significantly more nest-searching and foraging queen bumblebees than conventionally managed transects. However, on conventionally managed transects, there was no significant difference between farms with and without agri-environment schemes in numbers of nest-searching queens, and conventionally managed farms had more foraging queens.
Manage hedgerows to benefit wildlife (includes no spray, gap-filling and laying)
A replicated, controlled trial of the Rural Stewardship agri-environment scheme on five farms in Scotland (Lye et al. 2009) found that hedgerows dominated by hawthorn Crataegus monogyna or blackthorn Prunus spinosa were less attractive than field margins or grasslands to nest-searching queen bumblebees Bombus spp. in April and May. There was no significant difference in numbers of foraging or nesting queens between hedgerows managed under the agri-environment scheme (winter cut every three years, gaps filled, vegetation below unmown and unsprayed) and conventionally managed hedgerows. The study took place before the woody species comprising the hedgerow came into flower. Nest-searching and foraging queen bumblebees were recorded on six 100 x 6 m transects on each farm, once a week from 14 April to 16 May 2009, on dry days with temperatures of 5-25°C. Each farm had two arable field margin transects, two grassland (non-boundary) transects, and two hawthorn- or blackthorn-dominated hedgerow transects. On farms with the Rural Stewardship Scheme, one of each transect type was under the agri-environment scheme.
Pay farmers to cover the cost of conservation measures (as in agri-environment schemes)
A replicated, controlled trial involving 10 farms in east and central Scotland, (Lye et al. 2009) found that on farms managed under the Rural Stewardship Scheme, transects covering agri-environment options (unsprayed grassy field margins, species-rich grassland uncut from March-August and hedgerows only cut every three years) attracted significantly more nest-searching and foraging queen bumblebees Bombus spp. than conventionally managed transects. However, on conventionally managed transects (not agri-environment scheme options), there was no significant difference between farms with and without agri-environment schemes in numbers of nest-searching queens, and conventionally managed farms had more foraging queens. Five farms that signed up to the Scottish Rural Stewardship Scheme in 2004 were paired with five comparison farms less than 5 km away with similar land-use but no agri-environment participation. Bumblebees were recorded on six 100 x 6 m transects/farm, weekly in April-May 2009. Each farm had two arable field margin transects, two grassland transects and two hedgerow transects.
Plant grass buffer strips/margins around arable or pasture fields
A replicated, controlled trial in spring 2008 in Scotland, UK (Lye et al. 2009) found that on farms under the Rural Stewardship agri-environment scheme, 1.5 to 6 m-wide grassy field margins attracted higher densities of foraging queen bumblebees Bombus spp. in spring than conventionally managed field margins (more than three queens/100 m on grassy margins, compared to one queen/100 m on conventional margins). However, when counts on conventionally managed field margins were compared on farms with and without agri-environment schemes, farms without the agri-environment agreement had more foraging queens. This raises the possibility that farms with the Rural Stewardship Scheme agreement supported similar numbers of queens overall, but they were preferentially distributed on the agri-environment field margins. Margins on 10 arable farms were studied, five of which participated in the Rural Stewardship Scheme. Six habitat types were studied using 100 m transects on each farm: Rural Stewardship Scheme grass margin, conventionally managed arable field margin, species rich grassland, unfarmed grassland, Rural Stewardship Scheme hedgerow, conventionally managed hedgerow. The number of bumblebee queens within 3 m of the transect were recorded, once a week over a five-week period.
Restore/create species-rich, semi-natural grassland
A replicated, site comparison study in Scotland, UK (Lye et al. 2009) found that Rural Stewardship scheme species-rich grassland attracted more nest-searching queen bumblebees Bombus spp. but fewer foraging queens than areas of naturally regenerated, largely unmanaged grasslands. Five Rural Stewardship Scheme farms participating in the species-rich grassland management or restoration option were paired with five conventional farms. Across all farms, unmanaged grassland on conventional farms attracted the highest abundance of foraging queen bumblebees (over 4 queens/100 m transect on unmanaged grassland vs less than 3 on species-rich grassland), also in comparison with hedgerow and field margin transects. Unmanaged grassland transects had more nectar and pollen-providing flowers than species-rich grassland in April and May, when queen bumblebees are on the wing. Bees were surveyed once a week for five weeks April-May 2008, using a transect walk method.
