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| Dingy skipper (Erynnis tages) |
The first to appear is the dingy skipper (Erynnis tages) which flies from early May until mid-June. The species was first recorded in the butterfly park in 2022, the first iRecord observation on the Wirral since 2017 (Royden Park) and before that 2014 (Wirral Way, Caldy). It was confirmed as breeding in the butterfly park in 2023 and has been seen every year since. It has also been recorded recently in Prenton Dell Claypit and Port Sunlight River Park. Some rare good news on the butterfly population dynamics front.
By butterfly standards it is very plain with a spotted brown colour scheme giving rise to its common name. Identification is relatively straightforward as there is virtually nothing else that looks like it in the reserve. The only species I can think of that could possibly be confused with the dingy skipper is the burnet companion moth (Euclidia glyphica) that does fly at about the same time. However, it is a very different shape providing the butterfly opens its wings.
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| Burnet companion moth (Euclidia glyphica), which could possibly be confused with the dingy skipper |
The second species of skipper to appear is the large skipper (Ochlodes sylvanus) which flies from early June until as late as early September. It is a common butterfly throughout England and Wales and has been seen in the butterfly park for as long as I can remember.
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| The hooked antennae of a large skipper (Ochlodes sylvanus) |
The name ‘large’ skipper is something of a misnomer. It might be slightly bigger than a small skipper but it’s a small butterfly compared to species like the meadow brown and speckled wood. Identification involves distinguishing large skippers from small or Essex skippers and is based on two characteristics. First, the large skipper antennae have obvious hooked tips. Good eyesight can pick this up in the field but a pair of binoculars (or a telephoto lens) help. Secondly, the wings tend to be more heavily marked with pale spots and dark patches than the other two species. However, a word of warning is required as the markings of all three of the ‘orange’ skippers can be very variable. The photo shows a male. Gender can be distinguished by the shape of the abdomen (females are more pointed at the tip) and by the black sex brands running across his wings.
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| A male large skipper |
The other two orange skipper species are the small skipper (Thymelicus sylvestris) and the Essex skipper (Thymelicus lineola) that fly from July to late August. These have very different histories in the butterfly park. The small skipper, like the large skipper, has been there for as long as I can remember. However, the Essex skipper is one of many insect species migrating northwards as the climate warms. It is a little uncertain when it was first recorded in the reserve. My first record was in June 2023, but I think Chloe Aldridge saw one in 2022 and they may have been around in 2021. The uncertainty is because telling the two species apart is challenging and it takes a little while to convince people that Essex skippers have arrived in sites where they had not been recorded before.
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| Small skipper (Thymelicus sylvestris) |
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| Essex skipper (Thymelicus lineola) |
There are two characteristics that I’m comfortable using plus a third that I’m unsure about so I’m not going to describe it. The first is the sex brand. Small skipper males have bold sex brands that can be curved or wavy running obliquely across the forewings and are unmistakeable on fresh specimens as in this picture. Trouble is butterflies have a hard life and they can become faint or even disappear after a few dozen rounds of aerial combat, but if they’re clearly visible then the butterfly is undoubtedly a small skipper.
Essex skipper sex brands are shorter, fainter, straight and run parallel to the forewing leading edge. I sometimes use their presence for identification if the specimen is fresh and I’m sure it’s a male from abdomen shape but I’m never totally confident.
The second characteristic is the colour of the antenna nudum, which is orange for a small skipper and black for an Essex skipper. The first challenge is understanding what the antenna nudum is. I was amazed at how poorly documented it is on the internet. I expected to find annotated diagrams or photographs but could find neither. This has led to a riot of confusion with attempts to use antenna colour for skipper identification. Some say ‘use the colour of the front of the antenna’. Others say ‘use the colour of the antenna tip’. Both are half right as the nudum is a small bare patch on the tip of the front of the antenna. The small skipper in the photo above is displaying an orange nudum, which is the minute bright orange dot at the very end of its left antenna. This can be seen more clearly in the enlarged image. The colours of the rest of the antenna are highly variable. I’ve even seen one small skipper where the antenna was all black except for the orange nudum.
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| The orange nudum on the antenna of a small skipper |
Knowing what nudum means is only part of the problem for identification. One has to both see the nudum and then find a way to show it to others in an identification record. Once again, binoculars become a most helpful tool for field identifications. Getting the nudum in a photograph involves taking a view from below or a face shot such as this Essex skipper photo which clearly shows the black nudum of each antenna. Getting these shots isn’t too difficult. All that’s required is a little patience because the insects tend to go around in circles when feeding on a flower.
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| Getting the right angle to photograph the black nudum on an Essex skipper |
Blog post and photos - Roy Lowry
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