Although I have been observing and recording the wildlife of Leicestershire for many years, I still regularly come across species that I’ve never seen before. Sometimes it is just because they are very rare and with others I have just not been looking in the right places. However, many species start to appear just because they have recently migrated into our region. One of the most recent invaders is the Willow Emerald Damselfly, which can now be seen on many of our local rivers, canals and ponds. Before 2009 it had rarely been seen in this country, but since then it has spread steadily north and west, reaching Leicestershire in 2019. It is a delicate damselfly, dark metallic green in colour with pale brown wing markings. Unlike most of its close relatives, it spends a lot of time in the branches of willow trees and is on the wing well into October.

Other species take much longer to reach us due to their slower speed of travel and the shortage of suitable host plants. Rhododendron Leafhoppers were introduced from the United States in the early 1900s since when they have spread slowly through southern England. With their startling livery of scarlet, green and yellow, they are one of the most distinctive species although from a distance they appear as a small green-brown smudge no more than 1 cm in length. They are one of the very few species that feed on Rhododendron sap and they can be very numerous where they do occur.

The Comma butterfly is a species that almost died out in this country before making a spectacular comeback. It was formerly very common, feeding on Hop plants, but when hop farming declined in the 18th century they were confined to the counties close to the Welsh border. Over the last 50 years they have adapted to use common nettles as the larval foodplant and are now found throughout England and Wales. They are unusual in that they can be found at any time of the year; they hibernate over the winter months but awaken on warmer days to feed. There are two generations each year with the overwintering animals waking in March when they breed to give rise to the next generation that appears in June and July. The adults are orange-brown with dark markings and an unusual irregular edge to the wings; the name comes from a white ‘comma’ marking on the underwing.

We can definitely expect more migrants to move our way as the climate continues to warm. There are several species of dragonflies, moths and butterflies that have previously been recorded as occasional migrants from Southern Europe, but that are now naturally colonising the southern counties of England. It will be delightful to see these now species, but unfortunately their arrival will be accompanied by the loss of species that are unable to adapt to the warmer weather. Just one more reason why we all need to oppose any measures that will lead to further climate change.