Poor butterflies :(( and a question for some people

[Neil Jones]

In message <01c0285e$a20c0ef0$cff0ed96 at bug.m> David Chesmore writes:
> It is interesting that, while Neil Jones reports there has been a general
> decline in butterflies in the UK, some species have undergone rapid
> expansions, particularly in the North of England.  Two species that come to
> mind are the Speckled Wood (Pararge aegeria) and the Marbled White
> (Melanargia galathea).  The Speckled Wood has recently (last year and this)
> been recorded in East Yorkshire and appears to be expanding eastward.

These are both satyrids and grass feeders I suspect that they are therefore
a bit less vulnerable to the problems caused by habitat loss.

It may be due to the change in the climate. (I know that 4 or 5 years ago when
I mentioned this here you didn't accept it was happening but I think there
is now a broad scientific  consensus that it is a real phenomenon.)

Certainly both species show a tendency not to occur in colder areas.
The Specked Wood's occurence in western scotland being because of
its paradoxically milder climate.

There has certainly been a marked northward movement in some species.
We now have Dartford Warblers ( A bird whose scientific name
I don't know) nesting in Glamorgan. These were a very
southern species which suffered huge losses in cold winters.

> 
> The Marbled White, confined to the chalk on the Yorkshire Wolds has been
> colonising many new sites over the past decade and there are records some
> distance from the Wolds.  This species is interesting in that pre-1900
> records exist for sightings many km away from the Wolds; it then declined
> until there was only 1-2 known locailities in the 1960's.  It began
> expanding again in the 1970's and 1980's.  The reasons for such changes are
> not known.

Marbled Whites do some odd things. Here in South Wales they have an odd
distribution. There are some in the east and a band of colonies stretching
from the Gower Peninsula north into Carmarthenshire. 
There are odd sightings in between but there doesn't seem to be a permenant
colony anywhere.

The Gower colonies are on sand dunes but the Carmarthenshire colonies
are mostly on wet heathy mires or "Rhos Pastures" as they are called.
This habitat occurs in Glamorgan but the butterfly is curiously absent.
Glamoragan also has other coastal dunes.

One nice suprise was to find a Marbled colony on Butterfly Conservation's
nature reserve at Caeau Ffos Fach (K-aye-aye ffoss VahKH)
It  is an excellent example of Rhos Pasture (the Rh is an aspirate unvoiced
rolled R. It is Welsh for "heath") and had been bought as a
Marsh Fritillary (Eurodryas aurinia) colony.
 
> Another species doing well in my part of England is the Wall butterfly.
> Many have been seen.

It has been having real problems in some parts of southern England though.

> 
> It is also worthwhile noting that quite a few moth species have been
> expanding their ranges in recent years.
> 
> Dave

-- 
Neil Jones- Neil at nwjones.demon.co.uk http://www.nwjones.demon.co.uk/
"At some point I had to stand up and be counted. Who speaks for the
butterflies?" Andrew Lees - The quotation on his memorial at Crymlyn Bog
National Nature Reserve