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Other Reptiles
On the UK Mainland one particular species of
European lizard has gained a firm foothold. While we know some populations have
been introduced, the origin of others is uncertain. It may, indeed, be native in
some areas. This is the Wall Lizard.
One further lizard species, the Green Lizard,
is most unlikely to be native although there have been repeated introduction
attempts in the past (now, of course, illegal), many of which have survived for
a great many years. There is certainly one current breeding colony known in the
South of England.
Both of these species are native to Jersey in the
Channel Islands.
Wall Lizard (Podarcis muralis)

The Wall
Lizard (Podarcis muralis) can grow to about 20cms in total length, up
to two-thirds of which might be tail. It is a little larger than the
Viviparous Lizard. Pattern and markings are very variable but can be very
similar to the Viviparous Lizard's. It can also be differentiated from the
latter species by its rather pointed head as against the bullet-shaped head
of the latter. Both male and female can often be coloured quite a bright
green - not to be confused with the occasional green tint in the Viviparous
Lizard.
The Green Lizard Lacerta bilineata (formerly
Lacerta
viridis)

This is far and away the largest lizard you are
likely to see in this country. It can reach a total length in excess of
35cms. It is another bulky lizard rather like the Sand Lizard in build but
unlikely to be confused with this or any other species because of its size
and the overall green colouration. Some females and juveniles have two
noticeable white lines on each side of the back and in the latter case,
the base colour is brown rather than green. Mature males often develop
blue cheeks during the breeding season. Although the adult animals
appear to have no difficulty in surviving in our climate, historically the summers
have not been good enough to allow egg incubation over sufficient years to allow
colonies to become truly established. With global warming this
situation is changing and we certainly have at least one
population which has now been established and growing over a
number of years.
The Aesculapian Snake - Zamenis longissimus (formerly
Elaphe longissima )
A colony of unknown origin occurs in and around the
grounds of the Welsh Mountain Zoo in Colwyn Bay, North Wales, and has
existed there for 30-40
years. Numbers are unknown, but the colony is likely to contain at least
several dozen individuals. Reproduction appears to occur regularly, as
specimens of all size classes can be found, but at present, there is no
indication that the species has spread beyond the immediate vicinity of
the Zoo. Adults are unmistakable, being more or less uniformly olive or
brownish, often with light stipples on some scales. Juveniles can be
confused with juvenile grass snakes. However, they differ in having a
well-defined dark stripe from the eye backwards along the sides of the
head, which is not present in grass snakes, and in lacking dark edges to
most upper lip scales, which are conspicuous in grass snakes.

The European Pond Terrapin (Emys
orbicularis)

This Terrapin used to be native c. 8,000 years ago. It was presumed to
have become extinct due to climate deterioration. However, odd individuals
have been found in this country in recent years although we are uncertain if
they are breeding. It can only be conjectured whether these constitute a
remnant of the original population or are escapees from captivity.
The Red-Eared Slider (Trachemys scripta
elegans)

The Red-Eared Slider is another terrapin species which has become distressingly
common in the wild in the UK. It is not however, native, originating from
North America. All the individuals in the wild in the UK are the result of
escapes or deliberate releases. There is some suggestion that they may
represent a threat to wildfowl chicks and fish but there is
little evidence to substantiate this.
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