Over 100 species of butterflies have been recorded on Lundy, and some of them occur regularly in spectacular numbers. Visitors in the summer months will see many species of butterfly on the wing, including resident species such as the Large and Small Whites, Grayling, Small Copper, Meadow Brown and Small Heath. Migrant butterflies like the Painted Lady and Red Admiral turn up in late summer, and occasionally visitors from further afield like the Clouded Yellow will appear.
Day-flying moths often attract attention and the brightly marked Garden Tiger and Cream-spot Tiger Moth are amongst the most conspicuous. In sheltered spots where the Red Valerian grows, tiny Hummingbird Hawk-moths may be seen visiting flowers on sunny days. One of the least conspicuous day-flying moths is the Thrift Clearwing, which resembles a large fly. It flies on sunny days in mid-summer where Thrift is abundant, and is probably more common on Lundy than anywhere else in Britain.
The Five-spot Burnet Moth has shiny black wings with bright red spots and there are often hundreds visiting Thistle flower heads on summer days. Their empty cocoons may be seen on nearby grass stems. Most moths fly at night and are unseen by visitors, whilst during the day they rely on their camouflage to remain hidden on rocks, bark or lichens. One species of moth, the Lesser Yellow Underwing, appears in a colour form here unique to Lundy and Scilly, and a tiny micro-moth, Nothris congressariella, lives on Lundy and only two or three other spots in Britain, its larvae feeding in tiny burrows inside the leaves of Balm-leaved Figwort. Other species include the intricately patterned Angle Shades, Rustics, Silver Y and Carpet moths.
Whilst walking along the island’s many footpaths you may catch a glimpse of a dung beetle. Dung beetles are important nutrient recyclers, breaking down dung and incorporating it into the soil. This process not only improves the soil structure, but also reduces the numbers of other “pest” species such as flies which would otherwise breed on the dung. The dung beetles are so effective that they can consume twice their weight in dung every day. Two species of dung beetle are present on Lundy, the Dor beetle and the Minotaur beetle. Both are glossy black, with longitudinally ridged wing cases. The iridescent blue underside of the Dor beetle helps to differentiate the two dung beetles. In addition, the male Minotaur beetles have impressive horns which are used to defend the nest.
The list of invertebrates found on Lundy is extensive and many more are being discovered (please see Invertebrate research in the Research section for further information.)
Common slugs and snails receive a lot of attention from visitors to the island and the more colourful and unusual varieties are frequently seen. The Brown-lipped snail (pictured right) is often seen making its way across the paths snaking through Millcombe valley and comes in a variety of colours.
Tiger slugs capture the imaginations of our younger visitors and are often given new equally exotic names such as the giraffe slug and the leopard slug as they convey the patterning of the slug that has captured their interest.
Towards the end of summer, you may be lucky enough to see the dragon and damsel flies hunting, mating and holding territories around Pondsbury and other small areas of fresh water on the island. The common darter dragonfly and blue-tailed damselfly are those most regularly seen between mid June and October.