I walked down to a damp area of grass down by the River Bourne to the South of the village today, and found a Small Copper, Lycaena phlaeas. The Small Copper is an excellent small butterfly, generally seen only in small numbers but still found quite regularly - and its always a pleasure to see such a colourful and delightful insect.
Its numbers are recognised as declining, but this decrease is officially thought to be not so severe as to cause any serious concern of extinction at present - although there are differing views as to the whether this analysis, based on absence/presence in relatively large quadrat squares, is sensitive enough to pick up major declines in number within local areas. The geographical coverage as measured by 1 km squares, decreased as little as 15%, but numbers may have dropped by anything up to 90%, according to a recent transect study in North Wales. The species decline that has been recognised nationally has probably been associated with wholesale agricultural improvement and habitat loss.
However breeding success seems also to be quite dependant upon weather - better in warmer years, but on the other hand perhaps negatively affected by drought, when the sorrel food plants may suffer badly. Any effects of climate change are therefore likely to be complex. One effect that has already been recognised is a more rapid lifestyle with earlier peak appearances of the adult by 2 - 10 days.
The sun was low in the sky so this particular Small Copper oriented itself at a steep angle in order to bask most effectively in its rays - the shadow of its wing can be seen on the other stem of the Bristly Oxtongue plant behind! This is very important for butterflies as they have to thermo-regulate so carefully in order to function at optimum efficiency. It may very well even have carefully chosen its particular perch for convenience to make it easier to balance as it tipped so sharply towards the vertical. In fact this butterfly may be used to being nearly completely upside down, as both sexes tend to roost head down on grass stems at night.
The butterfly is said to exist in small colonies, with relatively few adults on the wing at any one time - so its nice to think that this one sighting might represent a colony in this area by the Bourne! This one should be an example of the second generation. We would normally expect three generations a year, peaking in late May, August and late September, with occasionally four generations in an exceptional year.
The primary larval foodplants are all Docks, Rumex species, Common Sorrel (R. acetosa), Sheep's Sorrel (R. acetosella) and sometimes Broad-leaved Dock (R. obtusifolius). The adults tend to be found in the variety of open areas where these plants are found, and will nectar there on Fleabane and a large variety of other members of the daisy family, heathers, buttercups and clovers. There is plenty of Fleabane, and other Asteraceae, in flower in this particular area at the moment.
The Small Copper tends to be a very active butterfly, fast-flying and often remaining mobile while nectaring. Males defend small territories while females characteristically fly low while hunting for egg-laying sites. The eggs are laid singly on the underside or upperside of dock leaves, white at first then grey, and last for two to three weeks. The larvae hatch and feed in grooves eaten out of the underside of the leaves (windowing). The overwintering generation hibernates as one of the first three instars. Pupation is low down on, or by, the food plants.
Its quite a variable butterfly with a very large number of colour forms. The Irish subspecies hibernica is differentiated from the British suspecies eleus by a more greyish colour on the underwings.
Its numbers are recognised as declining, but this decrease is officially thought to be not so severe as to cause any serious concern of extinction at present - although there are differing views as to the whether this analysis, based on absence/presence in relatively large quadrat squares, is sensitive enough to pick up major declines in number within local areas. The geographical coverage as measured by 1 km squares, decreased as little as 15%, but numbers may have dropped by anything up to 90%, according to a recent transect study in North Wales. The species decline that has been recognised nationally has probably been associated with wholesale agricultural improvement and habitat loss.
However breeding success seems also to be quite dependant upon weather - better in warmer years, but on the other hand perhaps negatively affected by drought, when the sorrel food plants may suffer badly. Any effects of climate change are therefore likely to be complex. One effect that has already been recognised is a more rapid lifestyle with earlier peak appearances of the adult by 2 - 10 days.
The sun was low in the sky so this particular Small Copper oriented itself at a steep angle in order to bask most effectively in its rays - the shadow of its wing can be seen on the other stem of the Bristly Oxtongue plant behind! This is very important for butterflies as they have to thermo-regulate so carefully in order to function at optimum efficiency. It may very well even have carefully chosen its particular perch for convenience to make it easier to balance as it tipped so sharply towards the vertical. In fact this butterfly may be used to being nearly completely upside down, as both sexes tend to roost head down on grass stems at night.
The butterfly is said to exist in small colonies, with relatively few adults on the wing at any one time - so its nice to think that this one sighting might represent a colony in this area by the Bourne! This one should be an example of the second generation. We would normally expect three generations a year, peaking in late May, August and late September, with occasionally four generations in an exceptional year.
The primary larval foodplants are all Docks, Rumex species, Common Sorrel (R. acetosa), Sheep's Sorrel (R. acetosella) and sometimes Broad-leaved Dock (R. obtusifolius). The adults tend to be found in the variety of open areas where these plants are found, and will nectar there on Fleabane and a large variety of other members of the daisy family, heathers, buttercups and clovers. There is plenty of Fleabane, and other Asteraceae, in flower in this particular area at the moment.
The Small Copper tends to be a very active butterfly, fast-flying and often remaining mobile while nectaring. Males defend small territories while females characteristically fly low while hunting for egg-laying sites. The eggs are laid singly on the underside or upperside of dock leaves, white at first then grey, and last for two to three weeks. The larvae hatch and feed in grooves eaten out of the underside of the leaves (windowing). The overwintering generation hibernates as one of the first three instars. Pupation is low down on, or by, the food plants.
Its quite a variable butterfly with a very large number of colour forms. The Irish subspecies hibernica is differentiated from the British suspecies eleus by a more greyish colour on the underwings.
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