The Comma butterfly with its very odd wing shape is an unusual and attractive resident of Hadlow parish, over-wintering as adults, in sheltered places in woodland for example. Like the other Nymphalids (Red Admiral, Peacock, Small Tortoiseshell) it is a bit of a wanderer, not restricted to particular colony sites, and individuals can be found in various places across the Parish.
Description
Commas are generally orange when first seen flying, and when examined more closely, the uppersides are a complex pattern of dark blotches on an orange ground, complicated by the outlandish and unique "serrated" wing shape. When they close their wings however, they appear completely different, camouflaged in a complex pattern that from a distance appears an overall dark grey.
This is a fairly fresh individual at the start of July 2017, possibly of the brighter Hutchinsonii form, that quickly lays eggs for a second generation that same year.
This individual is showing a little wear on the front edges, rear edges and a few other areas of the wings by the beginning of July, and I am fairly sure that it is an Hutchinsonii. The bodies of the adults are often quite plump:
Dene Park, 24-07-2012
Once the wings are completely folded, no sign of the orange upper wings remains, and the camouflage of a dead leaf, or of bark, becomes complete:
Distribution
Comma butterflies can be found over most of Hadlow parish in the summer, in woodlands, farmlands and gardens, and can be quite common in July to October in a good year. The over-wintering adults from the second generation (more rarely from the first), tend to be rather more limited in distribution and in the autumn might often be seen in gardens, before they move into woodlands to hibernate.
After hibernation, as they re-emerge in the spring, they are most likely to be found sunning themselves on footpaths through farmland or tracks through woodlands. Good footpaths are those around the Access Trail between Hadlow and Golden Green, the footpaths towards the River Medway and also the footpaths between the College's Equine Unit and Clearhedges Wood.
Nationally, the Comma went through a terrible numerical and range contraction in the 1800s, becoming confined to a few counties in the Welsh Marches by the turn of the century, becoming nearly extinct in the UK. However it has, amazingly, since the First World War, recovered all the ground lost, and now extends even into southern Scotland, after an absence of 140 years or more. The reasons for its decline, near loss and then remarkable recovery can only be guessed at.
Life cycle
Over-wintering adults mate in March, giving rise to the spring generation of caterpillars on nettles, and the "July" generation of adults. I think the butterflies seen in July are often quite likely to be the brighter "Hutchinsonii" form, which will mate and produce a second summer generation of caterpillars and adults appearing in August. These are darker and these are generally the butterflies that are likely to over-winter. However some of the first generation, the ones produced later, will also be darker and "too late" to breed in the summer, and will themselves over-winter, not breeding until the following March. Any of the "about to over-winter" individuals might well be found in gardens in September and October, feeding up ready for hibernation on flowers or rotting fruit.
Traditionally the caterpillar food plant was hops, grown almost everywhere for the brewing of beer for about a thousand years, but with the decline of its cultivation for brewing, nettles or possibly elms are the usual foodplant of the Comma nowadays in the UK. The single glossy green eggs are laid on the upper surface of tender leaves, sometimes on the extreme tip. Plants chosen may often be on the edge of a wood, scrub or a hedge, almost never in the open countryside.
The caterpillar looks like a bird's dropping, with a splash of white at one end, and the chrysalis is designed to look like a dangling withered leaf.
Oddities
The dark patches, more enhanced in the over-wintering individuals, are created using chemicals such as melanin, using up scarce nitrogen, an element thought to be in short supply in the caterpillar's diet. The short-lived summer Hutchinsonii form may sacrifice some of its ability to protect itself with melanin by diverting nitrogen into more rapid reproduction in some way, then dying soon afterwards.
Like many other butterflies, an adequate salt supply may be essential for optimum activity and successful reproduction (especially by the female, salts may be involved in nuptial gifts from the male?). Butterflies may therefore be found apparently taking salt from paths, car tyres, or even as in this case, dog's mess!
Predators and parasites
Birds are a major threat. The overwintering generation lasts longer and is therefore darker above than individuals of the short summer generation of bright Hutchinsonii, helping to reduce predation. When the over-wintering butterflies close their wings however, as they will do when actually hibernating, and as seen above, their camouflage of a dead leaf is almost perfect, and the insects can be very difficult to spot indeed!
Description
Commas are generally orange when first seen flying, and when examined more closely, the uppersides are a complex pattern of dark blotches on an orange ground, complicated by the outlandish and unique "serrated" wing shape. When they close their wings however, they appear completely different, camouflaged in a complex pattern that from a distance appears an overall dark grey.
This is a fairly fresh individual at the start of July 2017, possibly of the brighter Hutchinsonii form, that quickly lays eggs for a second generation that same year.
Dene Park 01-07-2017
This individual is showing a little wear on the front edges, rear edges and a few other areas of the wings by the beginning of July, and I am fairly sure that it is an Hutchinsonii. The bodies of the adults are often quite plump:
Dene Park, 04-07-2017
This photo shows the long hairs on the upper side of the wings close to the abdomen, that might help with trapping warm air. I haven't seen anything in the literature to support this view though. Alternatively, perhaps they help stop cold rain getting to the abdomen?
Dene Park, 04-07-2017
Once the wings are completely folded, no sign of the orange upper wings remains, and the camouflage of a dead leaf, or of bark, becomes complete:
Weald Way from West Peckham, 06-10-2012
West of Hartlake Bridge, 27-06-2014
Comma butterflies can be found over most of Hadlow parish in the summer, in woodlands, farmlands and gardens, and can be quite common in July to October in a good year. The over-wintering adults from the second generation (more rarely from the first), tend to be rather more limited in distribution and in the autumn might often be seen in gardens, before they move into woodlands to hibernate.
After hibernation, as they re-emerge in the spring, they are most likely to be found sunning themselves on footpaths through farmland or tracks through woodlands. Good footpaths are those around the Access Trail between Hadlow and Golden Green, the footpaths towards the River Medway and also the footpaths between the College's Equine Unit and Clearhedges Wood.
Nationally, the Comma went through a terrible numerical and range contraction in the 1800s, becoming confined to a few counties in the Welsh Marches by the turn of the century, becoming nearly extinct in the UK. However it has, amazingly, since the First World War, recovered all the ground lost, and now extends even into southern Scotland, after an absence of 140 years or more. The reasons for its decline, near loss and then remarkable recovery can only be guessed at.
Life cycle
Over-wintering adults mate in March, giving rise to the spring generation of caterpillars on nettles, and the "July" generation of adults. I think the butterflies seen in July are often quite likely to be the brighter "Hutchinsonii" form, which will mate and produce a second summer generation of caterpillars and adults appearing in August. These are darker and these are generally the butterflies that are likely to over-winter. However some of the first generation, the ones produced later, will also be darker and "too late" to breed in the summer, and will themselves over-winter, not breeding until the following March. Any of the "about to over-winter" individuals might well be found in gardens in September and October, feeding up ready for hibernation on flowers or rotting fruit.
Traditionally the caterpillar food plant was hops, grown almost everywhere for the brewing of beer for about a thousand years, but with the decline of its cultivation for brewing, nettles or possibly elms are the usual foodplant of the Comma nowadays in the UK. The single glossy green eggs are laid on the upper surface of tender leaves, sometimes on the extreme tip. Plants chosen may often be on the edge of a wood, scrub or a hedge, almost never in the open countryside.
The caterpillar looks like a bird's dropping, with a splash of white at one end, and the chrysalis is designed to look like a dangling withered leaf.
Oddities
The dark patches, more enhanced in the over-wintering individuals, are created using chemicals such as melanin, using up scarce nitrogen, an element thought to be in short supply in the caterpillar's diet. The short-lived summer Hutchinsonii form may sacrifice some of its ability to protect itself with melanin by diverting nitrogen into more rapid reproduction in some way, then dying soon afterwards.
Like many other butterflies, an adequate salt supply may be essential for optimum activity and successful reproduction (especially by the female, salts may be involved in nuptial gifts from the male?). Butterflies may therefore be found apparently taking salt from paths, car tyres, or even as in this case, dog's mess!
Dene Park, 26-07-2012
Predators and parasites
Birds are a major threat. The overwintering generation lasts longer and is therefore darker above than individuals of the short summer generation of bright Hutchinsonii, helping to reduce predation. When the over-wintering butterflies close their wings however, as they will do when actually hibernating, and as seen above, their camouflage of a dead leaf is almost perfect, and the insects can be very difficult to spot indeed!
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