Butterflies of Britain
Family - NYMPHALIDAE
subfamily - SATYRINAE
Tribe - SATYRINI
subtribe - COENONYMPHINA
Coenonympha pamphilus, Heyshott Down,
This is one
of the most widely distributed species in the Palaearctic region,
being found throughout most of Europe, including most of the
Scottish islands, most of the Mediterranean islands, and east across
temperate Asia to Mongolia. It is also widespread across most of
Prior to the 18th century the male Small Heath
was called the Selvedged Heath Eye, and the female was known as the
Golden Heath Eye. These names refer to the small but prominent
ocellus at the apex of the forewing. Later it was realised
that both "Heath Eyes" were the same species, which became known as
the Gatekeeper, although that name is now associated with a
different species - Pyronia tithonus.
The name Small Heath was proposed by the famous 18th century
entomologist Moses Harris, in his book "The Aurelian".
In continental Europe there are several other
similar Coenonympha species, but all of
these have prominent ocelli on the underside hindwings. In Britain
the only species with which pamphilus
can be confused is the Scottish race of the Large Heath
C. tullia, which has almost identical
markings, but is much larger in size.
resting / basking posture amongst grasses ©
common name, this is not primarily a heathland species, although
populations do occur on the heaths of the New Forest and elsewhere.
It is in fact found across a wider range of habitats than any other
British butterfly - occuring on open grassland, mountainsides, road
embankments, old quarries, cliff tops, sand dunes, heaths,
moorlands, meadows and around field margins. It also occurs
sparingly in woodland where it can be found in clearings and along
wide grassy avenues.
is most abundant at warm, well-drained, south-facing sites which are
lightly grazed to produce a sparse sward of fine grasses. At such
sites populations can sometimes be enormous, although they fluctuate
dramatically in response to grazing and climate.
Cerne Abbas, Dorset ©
In most areas
of Britain the butterfly produces 2 broods, the first of which
emerges as early as late April at the warmest sites, but usually in
mid May elsewhere. Most areas produce a 2nd generation emerging in
August and September, but in mountainous regions and in the far
north there may be only a single generation, emerging in June.
Emergence times vary considerably from site to site.
Thus it is possible to
see the Small Heath on the wing at almost any time between April and
October by visiting appropriate sites.
The eggs are
spherical and can be either pale green or straw coloured, with
reddish blotches. They are laid singly at the base of grass blades.
The larva has several colour forms, varying from
pale green to reddish-brown, but always with narrow white stripes,
and tiny, twin pink and white prongs at the tail end. It feeds
openly in daylight on tufts of Festuca,
Agrostis and other fine grasses.
Some of the first brood
larvae feed up quickly to produce adults in August, but others feed
more slowly, with larvae of both broods entering hibernation in late
September, some being quite small, while others may be half grown or
almost fully developed. They
over-winter at the base of the grasses, and resume feeding in late
pretty pupa hangs by the cremaster from grass stems, and is pale
green, marked on the wing cases with black stripes.
In the spring the
butterflies nectar mainly at daisies, but the summer generation
insects visit a much wider range of flowers including small
scabious, marjoram, clover, thyme and heathers. Both broods however
only visit low growing flowers, and rarely if ever nectar at taller
plants such as knapweeds, hemp agrimony or thistles.
Small Heaths often settle on
stones. The heat reflected back helps the butterfly to maintain a
high body temperature and high energy levels needed for instant
Males fly rapidly,
zig-zagging or flying in tight circles just above the grasses, but
rarely cover any distance. They frequently settle amongst grasses or
on bare ground, and are attracted to small whitish objects such as
stones, lumps of chalk, or bits of dry wood. Second brood males
often settle on the pale flower-heads of stemless thistle or
stemless carline thistle.
When the butterfly first
settles it exposes the ocellus on the forewing apex for a moment, so
that any bird which has spotted it will aim it's beak at the false
"eye" target. After a few seconds when the butterfly feels safe it
tucks the ocellus out of sight behind the hindwings.
The butterflies spend
long periods lateral-basking ( basking with wings closed ). By
angling their wings to present the maximum wing surface to the sun
they can absorb enough solar energy to keep their body temperatures
high. Consequently they always have enough energy to instantly dart
up and intercept passing females, or to escape from approaching
predators. If on the other hand temperatures are high and the
butterflies need to reduce their body temperature, they tilt towards
the sun so that only the edges of the wings receive direct sunlight.
are mildly territorial - encounters with their own sex result in
aerial sorties in which the pair spiral upwards flying in tight
circles. When they reach a vertical threshold of about 3 metres
above the ground, they split up and each male returns to ground
level, although not usually to its original perch. With most
territorial species, it is usual for the intruding male to be the
loser in these battles, conceding defeat to the original "owner" of
the territory. In the case of the Small Heath however the larger of
the 2 males generally drives off the smaller, irrespective of which
was the intruder.
Females fly to the male
territories, flying about to attract the attention of potential
mates. Courtship is very brief - the female settles on the ground,
and the male nudges her with his head and then crawls alongside her,
curving his abdomen to make contact. Mated pairs can often be found
amongst grasses in late morning. If disturbed the pair will take
flight, the female carrying the smaller male to a bush or another
clump of grass. Copulation lasts about an hour.
pamphilus, copulated pair, Cissbury Ring, West Sussex ©
separating the females disperse over open grassland to lay their eggs,
spending what's left of their lives walking or fluttering about
amongst the grasses inconspicuously.
dusk approaches the butterflies migrate across their sites to areas
where there are long grasses and shelter from the wind. There they go
to roost for the night, sometimes facing head-downwards, typically on
grass-heads, plantain flowers or dead flowerheads of marjoram.