Insects have a surprising beauty of their own, as Guy Edwardes shows
Published in April ’10
Insects do not generally get the same attention as birds and mammals, perhaps because their size and habits mean that many species go unnoticed. Yet there are some very interesting, colourful and unusual insect species to be found in the Dorset’s wide range of natural habitats during the spring and summer months. All you need to know is where and when to look for them.
Many hundreds of species of moth occur in Dorset. Most of these are nocturnal, so can be difficult to see. A good way to discover the variety of moth species in your local area is to set up a white sheet close to a light bulb on a still, dry evening. You will be amazed by the sheer number and variety of different moths that are attracted to it, and there is always the chance that you will discover a rarity among the masses!
The elephant hawk moth is a relatively common moth in Dorset. Its impressive 2½-inch wingspan makes it one of our largest moths. It is also one of the most colourful. It tends to be found in gardens, damp woodlands and on waste ground where food-plants such as bedstraws, willowherbs and fuchsia occur. It is on the wing from May to July. The elephant hawk moth gets its name from the equally impressive caterpillar, which has a trunk-like snout. When threatened, it draws this snout in to increase the apparent size of its head and to reveal four large eye markings to alarm any potential predators.
Some of the first butterflies to appear include brimstone, orange tip, speckled wood and green hairstreak. All of these species can be found in and around our woodlands. Locations such as Thorncombe Wood near Dorchester and Wareham Forest are ideal for spotting these early butterflies. The disused quarries on the Isle of Portland are home to a wide range of butterfly species.
The marbled white is a distinctive black and white butterfly which is locally common in many parts of Dorset. It cannot really be mistaken for any other species. In mid-summer it can be found, often in large numbers, flying around areas of chalk downland and unimproved grassland. It is particularly abundant on the limestone grasslands along the Purbeck coast. Grazed meadows, railway embankments and roadside verges are also prime habitats. The adult butterfly has a noticeable preference for purple flowers, especially field scabious, thistles and knapweed, while the caterpillar feeds on several different species of grasses, with red fescue being a particular favourite.
Dragonflies spend much of their lives underwater as larvae, with some of the larger species remaining in this state for up to five years. They require clean pools and rivers with emergent vegetation that enables the larvae to crawl out. When their skin dries, the adult dragonflies can emerge. It can take a day or two before the insect acquires its full colours, at which point it begins to fight for territory along the water’s edge.
The best way to tell the difference between a dragonfly and a damselfly is the way they hold their wings when resting. Dragonflies hold their wings perpendicular to the body, whereas damselflies hold their wings parallel to the body. There is also a separate group called emeralds, which hold their wings at 45 degrees. Dragonflies are easiest to spot when they are on the wing during the middle of the day. However, for closer views, early morning and late evening can provide the best opportunities, as some species settle on low vegetation overnight.
The beautiful demoiselle can be found on many of Dorset’s faster-flowing rivers. It is one of our most attractive dragonflies, with a metallic green body and coloured wings. Its distinctive flight is rather butterfly-like and it can be seen on the wing from late May to late August.
It is vital for us to maintain the habitats that all these insects require. A healthy population of insect life leads to a healthy and diverse ecosystem where the reptiles, birds and mammals that feed upon them can thrive.
Some other good places to find insects in Dorset
A great place to search for many species of insects, particularly butterflies and dragonflies. There are colonies of wood white, purple emperor, marsh fritillary and brown argus butterflies. The best location to view a wide range of species is the railway line that runs through the reserve.
The unimproved grassland found on many of Dorset’s Iron Age hillforts holds a healthy population of butterflies, moths, beetles, crickets and grasshoppers. The ditches and banks provide shelter from strong winds, while the south-facing banks provide an early sunny spot for insects to warm up. Head for sites such as Badbury Rings, Hambledon Hill, Eggardon Hill and Maiden Castle.
Moors Valley Country Park
Twenty-seven different species of dragonfly and damselfly can be found at Moors Valley Country Park, where the clean waters provide an ideal habitat. This is one of the best sites in the UK for dragonflies.
Arne RSPB Reserve
Arne provides a home for some of our most specialised insects which depend upon this increasingly rare lowland heathland habitat. Particular specialities of this reserve are the silver studded blue butterfly and the downy emerald dragonfly. Eight hundred species of moth have been recorded here along with thirty species of butterfly and twenty species of dragonfly and damselfly.
Lowland heathland is a rare habitat in the UK and Dorset holds some of the best examples. Studland Heath (particularly the area around Little Sea) is a great place to find many species of dragonfly and damselfly. Sites such as Gore Heath, Stoborough Heath and Canford Heath all hold good populations of typical heathland insects such as green tiger beetle, wood ant and silver studded blue butterfly.