Let's not say goodbye to the butterflies in the Midlands
It's sad but true, butterfly numbers in Britain are on a downward spiral. A number of National Trust properties in the Midlands actively monitor butterfly numbers as part of the UK Butterfly Monitoring Scheme. We hope it will help us to better understand the reasons behind the fall in numbers and help to improve the situation. Even properties not directly involved in the scheme play a massive part in providing suitable habitats in their parks and gardens.
We have to carefully manage our gardens and landscapes to create and maintain diverse natural habitats for our wildlife. Habitat loss is the number one reason for the dip in butterfly numbers, with some species having very specific needs to thrive and breed. Farming and forestry, although essential, have a huge impact on insect habitats, but innovative management systems can help. Specialised grazing systems using low numbers of native cattle and sheep allows a variety of flowers and grasses to grow which provides a mixture of tall and short vegetation.
Examples of projects which have benefitted butterflies include the holistic grazing scheme at South Park, Croome, which has transformed a heavily grazed area of limited value to thriving grassland. Wildflowers and grasses can flower freely, providing abundant nectar sources for adult butterflies and good breeding conditions for species such as Essex skipper and marbled white whose caterpillars eat grasses.
On the Long Mynd, populations of the grayling – a regional rarity, whose larvae feed on fine-leaved grasses - have increased in response to less intensive grazing.
Clever management of woodlands creates sunny glades, young and old trees and deadwood, all of which play a vital part in the butterfly life cycle. A great example is the wood-pasture restoration at Croft castle, where dense conifer plantations have been removed. The reintroduction of native trees and grassland have already attracted scarce species such as silver-washed and dark green fritillaries. There has been an increase in native flowers which we hope will attract the wood white, one of Britain’s most threatened butterflies.
Improving diversity in our parklands
Kedleston is just one example of a property where the parkland is being managed to increase the diversity of flowering plants within the grassland. We've already seen a good improvement in numbers of ringlet, meadow brown, gatekeeper and small tortoiseshell. The mature trees are also supporting populations of rarer butterflies like the purple hairstreak and white-letter hairstreak. Only time will tell if our hard work is paying off!
Butterflies are recorded in a fixed width band (typically 5m wide) along the transect each week from the beginning of April until the end of September. At Hardwick Hall there are monitoring transects in the parkland and the gardens to demonstate how having a variety of habitats greatly increases the diversity of butterflies that can be spotted. The painted lady is a regular favourite here; this species migrate each spring to England from the desert fringes of North Africa, they gradually move up the country with each breeding cycle and, in the autumn, many of the last brood will attempt the return migration to North Africa.
We also undertake Wider Countryside Butterfly Surveys (WCBS), based on surveys of 1km squares randomly allocated by Butterfly Conservation. We have established established WCBSs at Attingham, Brilley and Charlecote, with one due to start at Dudmaston this year.These specifically to track the butterflies on farmland owned by the NT and compare them with trends on non-NT farmland.
Not just a garden favourite
Butterfly monitoring also takes place across the Peak District as well, Dovedale valley has some distinct habitats thanks to the underlying geology and less intense agriculture. The mosaic of broadleaved and coniferous woodlands, grasslands and exposed rock attracts specialist butterfly species. On long summer days you mights spot a green hairstreak, green-veined white or orange tip and as summer draws to a close you'll see plenty of ringlet and meadow brown butterflies.
A rare sight
In the Dark Peak you might be lucky enough to see rare butterfly species. Upland and moorland habitats provide specialist food and shelter for butterflies with very specific needs to thrive. The steep valley woodlands, rolling grassland and heathland attract rare butterflies like the hairstreak butterflies high in the tree canopy and small heaths flitting through the long grass. Why not download a spotter guide to see who to look out for?
What does the future look like?
The National Trust has further plans to help butterflies in the Midlands area from habitat restoration projects to working with other land owners to connect areas with good butterfly populations so that they can move through the landscape.
At Hanbury Hall we manage hedgerows to provide suitable breeding habitat for the brown hairstreak, whose larvae feed on blackthorn. Regionally this butterfly in confined to an area of east Worcestershire, with Hanbury at the northern edge of its limited range.