About this guide
These web pages show the butterflies with resident colonies in the
counties of Gloucestershire and South Gloucestershire, England.
Common migrants and recently introduced species are also shown.
The guide is based on observations made during 1975 - 1999.
The guide is in four sections:
- Introduction - this section, which gives background information
about the area covered and butterfly recording within it, and about the
contents of the species pages
- Species - there is one page for each of the butterfly species.
The main species index is text-only,
and there is also a photo index grouping
species by type, with one page of photographs for each group
- Habitats - this describes and
illustrates the main types of butterfly habitat in the area, including
some of the sites open to public access
- Conservation - this section
indicates some of the conservation issues, particularly habitat loss
caused by lack of appropriate management
Gloucestershire and South Gloucestershire countryside
The area is shown in green on the map, with ground over 175m in
altitude shaded. The Cotswold Hills are in the east, the Forest
of Dean in the west, and the river Severn divides the county as
it runs southwards into the Bristol Channel.
The Cotswold Hills rise steeply from the Severn Vale.
Within them there are many hillsides and valley slopes
which are too steep for growing crops. Cattle and sheep are
farmed on grassland, though much of it is "improved" by
the use of fertilisers.
Although much reduced in total area during the 20th century,
there are still many patches of unimproved flower-rich grassland in the
Cotswold Hills. There are also many woods. There is a long tradition
of quarrying Cotswold limestone for buildings and field walls, resulting
in numerous disused quarries.
The Forest of Dean has large areas of forestry plantation, deciduous and
coniferous, and also the remains of heathland which was more extensive in
the past. Old industrial sites (from quarrying and coal mining), disused
railways and the many wide woodland tracks provide relatively open habitat
for butterflies. So too do recently-felled blocks of woodland.
The Severn Vale is quite intensively farmed. Some of the woods
in the Vale have good populations of the woodland butterfly species.
Unimproved grassland is scarce, and some butterflies found quite commonly
in the Cotswolds and the Forest of Dean are uncommon or absent in most
of the area.
In the north-west, the Malvern Hills just reach southwards into the
county. From the south-east corner at Lechlade westwards along
the course of the river Thames towards its source at Kemble, there
are many lakes resulting from gravel extraction.
Butterfly recording in the area
Several organisations encourage butterfly recording in Gloucestershire.
Most of the records used to produce the species distribution maps were
made by members of
the British charity dedicated to saving wild butterflies, moths and
their habitats. Butterfly Conservation ran a
project, taking records from the 1995 to 1999 seasons to show
distribution of butterflies throughout Britain and Ireland.
The Atlas was published in 2001 (ISBN 0 19 850565 5).
I was Butterfly Recorder for the Gloucestershire branch of
Butterfly Conservation from 1994 to 2000.
Naturalists Society (GNS) encourages its
members to record all forms of wildlife, and to pass their records to the
appropriate recorder. I was Butterfly Recorder for the GNS from 1981 to 2001.
Gloucestershire Wildlife Trust (GWT) runs a local
wildlife records centre for Gloucestershire, the Gloucestershire
Centre for Environmental Records (GCER). The GCER's records are used for
conservation purposes including advice to councils and government
agencies such as English Nature. I provided butterfly records and
site information to the GWT.
The Bristol Regional Environmental Records
Centre (BRERC) covers the former county of Avon, including
the area which is now South Gloucestershire. The Avon Butterfly Project
organises butterfly recording in that area. I exchanged
South Gloucestershire records with BRERC.
Members of various other wildlife and conservation-oriented organisations
also provided records. Directly or indirectly, at least 360 people
contributed to a total of over 85,000 records from 1975 to 1999.
I personally made over 25,000 of these records, and enjoyed visiting
not just the best (and well-recorded) butterfly sites but also many other
interesting places throughout the area.
The information shown for each species includes:
- Species name and scientific name - I have used the scientific
names given in some recent books, with an alternative genus name shown in
brackets in cases where the books differ
- Photographs - a selection of photographs of the adult butterflies,
and in a few cases also of an earlier stage. Identification features are
pointed out in some cases where there are two very similar species.
The photographs are mostly from Gloucestershire sites. They are
all highly compressed JPEG images, to reduce file sizes and
transfer times over the internet
- Habitat - the type of place where you might expect to see
the species when the adults are flying. Photographs of some
suitable habitats are shown
- Conservation issues - any particular concerns about the species.
More general conservation topics are mentioned in the
Conservation section of the
- Flight Period - the best time(s) to see the species in an
average year. Weather conditions may result in an earlier or later
flight period, and there are often some much earlier and later
individuals compared to the majority of their generation.
A few species hibernate as adult butterflies (rather than at
an earlier stage of egg, larva or pupa). Particularly warm days may
bring them out of hibernation at any time during the winter
- Distribution - a brief description of where the species occurs
in the area
- In most cases, a dot-map at 2Km scale (using the even-numbered
grid lines on Ordnance Survey maps) shows records made during 1995 - 1999
as solid dots, and other records from 1975 - 1994 as open dots.
For species recorded in less than 20 2Km x 2Km squares since 1995, no map
is shown because of the vulnerability of the remaining colonies
(a Conservation issue)
- An open dot, or no dot at all, does not necessarily mean the absence
now of the species from the location, just the absence of a recent record.
Some of the records shown are of "wanderers", specimens seen quite far
from their nearest breeding habitat. There are comments about this on
some species pages. Specimens of some species have been deliberately
released into the wild
(another Conservation issue)
- The commonest species occur almost everywhere in the area, so gaps
on their distribution maps indicate a lack of sufficient records to
provide full coverage.
- For some of the less common species, particularly
those restricted to unimproved limestone grassland in our area, a lot
of effort has been put into finding their colonies during the past
20 years, with special checks during 1995 - 1999 for the continued
existence of colonies known from earlier years. For such species,
the solid dots give a reasonably accurate indication of their current
- Above each map is a chart showing when records were made,
excluding late autumn and winter months. The bar heights in the chart
reflect relative numbers of records made and butterflies counted (where
this information was available). Weather conditions affect flight
periods, so in any one year the flight period for a generation of the
species is unlikely to be quite as long as shown on its chart. In many
cases, there are a few exceptionally early or late records for the
species shown as very short bars
Need a book on British butterflies to use out in the countryside?
For a field guide with illustrations of adult butterflies and
early stages (eggs, larvae and pupae), one book I would recommend
is the Hamlyn Guide to the Butterflies of the British Isles
by J A Thomas
First version February 2000
Revised to use additional records, March 2000
Links revised October 2005
© Guy Meredith