70
THE ESSEX NATURALIST
7 am of [the] opinion that the grey squirrel can never become wide-spread
and dominant like our other introduced animals, the rabbit and the brown
rat' (Watt 1923).
Pre-1960 Grey Squirrel Records
Grey Squirrels were introduced to the British Isles at a number of points
in the late nineteenth and early twentieth centuries. No actual introduc-
tions were made to Essex, nor anywhere in East Anglia, the nearest intro-
ductions being those at Woburn in 1890 (ten animals) and Regent's Park
during 1905-7 (91 animals) (Middleton 1931a). From the introductions
made around London the Grey Squirrel spread rapidly north, south and
west, but virtually no eastward movement occurred.
In the early part of this century occasional Grey Squirrels were reported
from Essex, but these animals never established permanent colonies. The
pre-1930 records are listed in Table 2.
Table 2
Pre-1930 Grey Squirrel records
It has been suggested that the spread of the Grey Squirrel into Essex
was hindered by the geographical barrier of the Lea Valley, with its
industrial area in the south and treeless areas and reservoirs to the north.
As a result, the permanent invasion of Essex had to occur well up the Lea
Valley, actually occurring at Roydon in 1933, and from there the animals
moved south towards Epping Forest. During the 1934-35 Grey Squirrel
Survey Middleton (1935) only received three reports of Grey Squirrels in
Essex, and commented that 'in Epping Forest only an occasional grey
squirrel has been seen'.
However, in Epping Forest in December 1935 a pair of Grey Squirrels
was seen in Bury Wood. In the following two years the spread of the Grey
Squirrel in Epping Forest was documented by Johnston (1938), who also
described in detail the control measures enforced. As a consequence, by
the end of the summer of 1937, 150 Grey Squirrels had been destroyed.
Johnston further commented that although Grey Squirrels were still
present the threat to the native species had passed its most critical stage!
Dent (1937) recorded the first Grey Squirrel at Nazeing just outside the