Moths in North Wales

Moths and Butterflies

No fundamental distinction can be made between moths and butterflies. All these insects belong to the order Lepidoptera; it is just that, in the English language, we choose to call some butterflies and the remainder moths. It is true that the butterflies are all closely related to each other but there is no single* character that distinguishes them from all moths. Perhaps the most useful character is the presence of clubbed antennae in all (British) butterflies although a few moths do also possess this feature. Other differences that are sometimes cited are that butterflies are day flying (true) whilst moths fly by night (not always true) or that butterflies rest with their wings held differently (not always true). Again, it is often thought that butterflies are more brightly coloured than moths but there are plenty of exceptions – see the examples below.

* A distinction can be made if two characters are taken into account: butterflies have clubbed antennae but lack a frenulum.

Click on an image to enlarge the photograph.

Moths: a few facts

Moths greatly outnumber butterflies both in terms of numbers of individuals and the number of species; in fact there are over forty species of moth for every butterfly species in North Wales. Moths are all around us and can be found in every habitat from the seashore to the mountain summits. They can also be seen on every day of the year, given suitably mild weather conditions, as a few species are active throughout the winter months.

For convenience, a distinction is made between the macro-moths and the micro-moths but this is rather similar to the distinction between butterflies and moths in that it is an arbitrary human divide. Thus, most micro-moths are smaller than most macros but many micros are larger than some macros; it is mainly a matter of convention as to which families are considered to belong to each category.

Some micros are extremely small and, in fact, what is alleged to be the world’s smallest moth, Enteucha acetosae, is found in North Wales. This moth is only 1 ½ to 2mm long, making it quite unnoticeable in ordinary circumstances. If it were not for the evidence left by the leaf-mining larvae it seems unlikely that we would ever suspect their presence.

At the other end of the size scale are the Hawk-moths. Some of these are surprisingly common, e.g. the Poplar Hawk-moth, the larvae of which feed on Sallow. However, the very largest species are scarce migrants, the Death’s-head Hawk-moth being the biggest, with a wingspan up to 135mm, and the rather more frequent Convolvulus Hawk-moth the second biggest. Both these impressive insects were recorded in North Wales in 2003.

How to see moths

Although moths are so ubiquitous, most people live out there lives without ever appreciating the variety and interest of these insects. The best way to learn about moths is to start light trapping and an excellent introduction to this is to attend one of the many public events organised by your branch of Butterfly Conservation. Be warned that this can be a life changing experience. The first experience of light trapping has been likened to swimming over a coral reef for the first time - one just cannot believe the amazing beauty and diversity which one previously failed to appreciate!

Scarce Moths in North Wales

Fortunately, many of our moth species are still common but of course there are some that are not. Scarce moths tend to be scarce for a reason that is easy to comprehend, such as requiring a larval foodplant that is scarce. However, some moths are scarce for other less obvious reasons. Thus, oak trees support a host of different species and since oak trees are currently abundant, even in our highly manipulated countryside, most of these species are common. However, a few moths, e.g. the Orange Upperwing and Common Fan-foot, are inexplicably rare (and the former may even be extinct in Britain) even though the larvae feed on oak.

The scarce moths of North Wales are listed on the following three pages.

UK Biodiversity Action Plan Priority Species

BC National Action Plan for Wales - High Priority Species

BC National Action Plan for Wales - Medium Priority Species