Species now extinct in England
Five butterfly species have become extinct as breeding species in England and a sixth (the large tor-
toiseshell) may now also be lost. Of the five definite extinctions, only two (the mazarine blue and the
black-veined white) ever bred in Essex. In both cases the species disappeared from Essex well before it
was finally lost from England. In neither case has a convincing explanation for the extinction been put
forward; the losses occurred well before major agricultural changes now widely blamed for
butterfly declines.
The large tortoiseshell was widespread and quite abundant in Essex during the 1940s and early
1950s as it was in much of south-east England (see Heath et al.pp94-95). It seems to have been rarely
seen earlier this century and has declined rapidly since then. The decline occurred well before the
ravages of Dutch elm disease affected the larval food-plant. Like the two earlier extinctions the cause is
a complete mystery (Heath et al.) although there is considerable evidence that large tortoiseshells
were only temporary residents in Britain: becoming established for a few years after major immigra-
tions. Scattered records of adults (but not of larvae) have occurred in some years, often in 'good' years
for other migrant vanessids. If this species should ever become re-established in Britain following such
immigrations, it will be the first species of butterfly to colonise or recolonise the country (unaided by
man) since records began.
Species extinct in Essex but still resident in England
In addition to the three species discussed above, there are 16 species which are known to have bred
in Essex which do not do so at the present time. Although vagrants are recorded in some cases and
one species may be re-established. These species fall into several quite distinct groups based on
when they disappeared from Essex and their ecological requirements.
The early loss of downland pastures (see above) explains the loss of the chalk-hill blue, adonis blue,
small blue and silver-spotted skipper in the 19th century. The old records are from the chalky north-
west near Saffron Walden (Fitch, 1891) although, strangely, there are 19th century reports of chalk-
hill blues and small blues from Epping Forest: a distinctly unusual habitat for these species. These
species are never likely to recolonise the county.
The purple emperor, brown hairstreak, wood white, Duke of Burgundy fritillary, marsh fritillary and
heath fritillary are six species from five quite distinct families and each with a different larval foodplant.
What they share is an ecological similarity: they are all woodland species that were most abundant in
southern England and have all declined in national range (but with some considerable recent re-
expansion in the case of the wood white). All six disappeared from Essex in the 19th century and what
evidence there is suggests that they were never specially common in the county. Only once
(Douglas. 1842) was the purple emperor recorded as common in the north-east of the county. The
researches in old literature by Emmet (1978) have confirmed the rarity of most of these species in the
Epping Forest district in Victorian times. Heath et al.( 1984) suggest habitat changes related to the
cessation of coppicing may, in part at least, explain the decline in these species. This could explain
what happened in Essex - Epping Forest was never a coppiced woodland but a grazed wood-pasture.
The coppice woods elsewhere in Essex (including the now largely destroyed Ongar Park Woods near
Epping Forest) have more old records of some of these species although Epping Forest was renowned
as the best locality for the brown hairstreak (see Fitch, 1891). The marsh fritillary disappeared by the
middle of the 19th century. Some colonies away from Essex are in open boggy ground where the larval
foodplant, devils-bit scabious, grows profusely. The butterfly needs ungrazed foodplants that grow
large leaves (Heath et al.) and it seems likely that the Essex colonies would have been on wet rides in
woods rather than in heavily grazed wet pastures.
With the exception of the marsh fritillary and the Duke of Burgundy fritillary, these woodland
species have been found in Essex since their extinction as breeding species. Their recent status is
discussed below in the section on recolonisations and re-introductions.
The silver-studded blue is mainly a heathland species; it was common in heathy parts of Epping
Forest in Victorian times (Fitch, 1891) and until the middle of this century in the Brentwood area. Loss
of heathlands is the most likely cause of this species loss. A brief recolonisation of Essex, in the 1950s.
was by the chalk form of the species which bred for a while in the Grays Chalk Quarry.
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