Butterfly "Pararge Aegeria"

Description:

The scientific name: Pararge Aegeria Family: Nymphalidae Satyrinae.

Habitat:

It is often stated that butterflies make excellent "indicator" species, as their distribution ranges and population dynamics adjust rapidly in response to changes in the environment. This is particularly true of the Speckled Wood. The butterfly was widespread and fairly common in Britain until the late 19th century when it suffered a sudden and unexplained collapse in numbers. Then from the 1930's onwards it gradually expanded it's range : this species favours darker and damper woodlands than most other butterfly species, so it's populations expanded in response to the large scale conversion of coppiced woodlands to plantation management. Today the Speckled Wood is regarded as a common woodland butterfly, which breeds in damp areas where dappled sunlight filters through the trees. It can commonly be seen basking on low foliage, or on forest paths in deciduous woodland, but is quite tolerant of shade and can also be found in conifer plantations, where it breeds along grassy rides. In recent years it has demonstrated a favourable response to climatic change, having expanded into more open habitats, and can regularly be seen in gardens, along hedgerows, and scrubby areas of open grassland. It has also extended it's range northwards, now reaching Ullapool in n.w. Scotland.

Notes:

On sunny mornings the males take up residence in areas of woodland where dappled sunlight filters through the trees. Each male selects a "perch" in the form of a sunlit leaf, from which it can survey and intercept passing females. During the course of the morning, the changing position of the sun causes the various perching places to be periodically shaded, at which time each male has to move to establish a new perch. Inevitably this results in a high number of male-male encounters. When males meet, they engage in a sortie, spiralling up to the tree tops. This appears to be a test of strength, but probably also involves chemical messages. Either way, after a few moments a "winner" emerges to return to his chosen perch. Experiments have shown that the winning male is usually the one which first established his perch. The intruding male is ousted, and has to establish a new perch elsewhere in the vicinity. In experiments when 2 males have been introduced simultaneously into an area, and both believe they have ownership of a perch, the ensuing sortie can continue unabated for several minutes. Ultimately one of the combatants seems to get lost, or gets distracted, leaving the other to reclaim its perch. Some males adopt a different mate-location strategy, choosing to patrol in search of females. In his fascinating book Butterflies of Britain and Ireland, Jeremy Thomas states that "certain individuals - especially those possessing 4 spots on the upperside of each hindwing, are more inclined to perch, whereas males with 3 spots have a tendency to patrol". Males always intercept other Speckled Woods of either sex but usually ignore other species. When a receptive female is intercepted, she settles on foliage, and spreads her wings. The male then settles below her, and gently walks onto her hindwings. Butterflies have olfactory sensors on their feet, so this ritualised behaviour probably enables the male to "taste" her scent and determine whether she is recently emerged - vital information because younger females have a longer life ahead of them, and are therefore capable of laying more eggs. Copulation takes place in the late morning and lasts for about an hour. The adult butterflies feed mainly on honey dew ( aphid secretions ) on the upper surface of oak, ash or hazel leaves. The spring and summer adults rarely visit flowers, although I have at times seen them nectaring at wood spurge. In late summer males sometimes nectar at fleabane or knapweed flowers, but are more often seen feeding at the juices oozing from fermenting blackberries. Females prefer to feed on the sticky secretion which coats ash buds - individuals often spend several minutes at a time walking about on ash twigs, avidly feeding on the sticky secretion which coats the buds. They also visit the flowers of certain trees and bushes including pear, hawthorn, lime and buckthorn. Overnight and in dull, cold or wet weather, the butterflies go to roost in bushes - e.g. at Ballard Down in Dorset I have watched them go to roost in prickly gorse bushes, at Stansted Forest in West Sussex I have seen them roost in bramble bushes, and at Noar Hill in Hampshire I have watched them enter blackthorn and dogwood bushes in late afternoon.