Butterflies are some of our most attractive, best known and popular insects and are the epitome of beautiful summer days. There are 59 native species in Britain though the abundance of half of these has decreased in recent decades making them a good indicator of the health of the environment. Due to Devon’s diverse range of habitats nearly two-thirds of British butterflies can be found here and the County has strongholds for a number of rare species including the silver-studded blue and high brown fritillary.
Butterflies are fascinating creatures and valuable pollinators. The majority of a butterfly’s lifecycle is spent as a caterpillar, at which time they are very particular about their food plants. Encourage their food plants and the butterflies will follow. Adult butterflies have different food requirements, needing nectar which they suck up through straw-like mouthparts.
Butterflies tend to like specific habitats and this is essentially linked to the presence or absence of suitable food plants:
- Woodland – Dense woodland does not suit butterflies but those with open rides or clearings and surrounded by uncultivated grassland are ideal for species such as the hairstreaks, comma, peacock and speckled wood.
- Grassland – The majority of butterfly species breed on various types of grassland. They are, therefore, very vulnerable to agricultural intensification which eliminates their food plants. Some of the richest grasslands for butterflies are south facing slopes of chalk and limestone with a mosaic of grass heights. Butterflies such as blues, coppers, skippers and browns can all be found – sometimes in astonishing numbers.
- Heaths, moorland and bogs – Most heaths are dominated by heathers and often have their own characteristic and interesting butterflies such as the grayling, silver-studded blue and small heath. Moorlands are similar to heaths but at higher altitudes and generally wetter, where species such as the marsh fritillary (Europe’s fastest declining butterfly) can be seen.
- Hedgerows – Ancient hedges consisting of a variety of shrubs growing above a flower-rich, sheltered bank or broad verge are ideal for the caterpillars of the gatekeeper, comma, brown hairstreak and orange-tip caterpillars to feed on.
- Gardens – A well-stocked flower garden can attract large numbers of butterflies, albeit of a limited number of species. Red admiral, peacock and small tortoiseshell can all be a common site, as can the whites, for which the vegetable patch is a major breeding ground.
How to encourage butterflies
- Grow suitable plants in your garden to attract and feed butterflies such as lavender, marjoram, Michaelmas-daisies, sedum and thistles.
- Create a suntrap where banks of flowers grow in full sunshine with maximum shelter from the wind.
- Leave a few areas to go ‘wild’- brambles and thistles provide valuable nectar for adults and nettles and many other wild plants are the food plant for several different caterpillars.
- Encourage landowners to leave grassland strips next to hedgerows.
- Management of grasslands is critical, particularly for those with a high diversity of plant species. Create a tussocky sward with varying grass heights by selective grazing or cutting regimes.
- Carry out appropriate management of natural habitats to encourage butterflies e.g. scrub clearance from a heath, creating glades and rides within a woodland or creating wild flower areas.