THE STAG BEETLE IN NORTH-EAST ESSEX 167
The Stag Beetle in North-East Essex
By J. T. Clark
(Colchester Royal Grammar School)
The Stag Beetle (Lucanus cervus (L.)) is one of the largest and
most famous of British insects. Its portrait appears in practically
every popular book on insects. One would expect therefore that
such a conspicuous and well-known creature would have been
thoroughly investigated with regard to its distribution in this
country. It became obvious to me on my arrival at Colchester
that this was not so, for all sources of information clearly stated
that this was an insect that was mainly confined to the area South
of the Thames, particularly in the London district. On the other
hand the boys of the Grammar School all agreed that this was
an exceptionally common insect in the Colchester area. In 1962
I was able to confirm this by collecting considerable numbers from
the School grounds alone. Consequently it was decided that the
School Field Club should systematically record all occurrences of
the Stag Beetle during 1963—a survey which is summarised in
this article.
An account of the known distribution of the Stag Beetle in
Britain may prove of interest. Definite records are not always
easy to obtain. For instance, some County Field Clubs, although
believing the insect to occur in their county, possess no actual
records of either dates or localities. The first attempt to present
a picture of its distribution was made by Donisthorpe in 1941.
This took the form of a map showing in which vice-counties the
insect had been known to occur. This was of limited value since
no distinction was made between areas where it was regularly
common and those where it had been seen once only. The first
detailed distribution pattern was given by Hall (1961) for the
London area. The accompanying map (figure 1) shows its known
occurrence by ten-kilometre squares. This has been compiled
from some two dozen printed sources and from correspondence
with naturalists in the areas concerned. The circles indicate
squares where there is only one known record. Those with from
two to five records are shown as solid discs, whilst solid squares
indicate locations from which there are more than five records.
It can be seen that according to this map there are two
distinct centres—one in the London area and one in the Colchester
area—with a discontinuous occurrence along the South Coast. It
is possible that there is a third centre in Gloucestershire—certainly
this was the case in the past according to Fletcher (1941). Those
counties which appeared on Donisthorpe's map but from which I
have not been able to find location details are indicated by
question marks on the map.
One thing appears to be certain about the distribution of this
insect. It may be very common in one place and rare or absent
in the surrounding areas. This means that there are probably