The most common reptile encountered within the Clyde catchment, the common or viviparous lizard (Zootoca vivipara) are found in a huge variety of habitats within the area.
Adult Common lizard measure approximately 15 cm. They have long bodies and short legs. The colour and patterning of this species is very variable. They are generally mid-brown but they can be green, olive-grey or black with patterns of spots or stripes. They have a series of white spots down the flanks, which fuse to form a line, and a black line along the back. Common lizards also have numerous black spots scattered over the body. Males have orange/yellow bellies with black spots and females have cream/white bellies.
Adults emerge from hibernation in March, usually the males are a few weeks earlier than the females. Mating is between April and May. The females produce between 3 and 11 young in July, the young are born in an egg sac that breaks either during birth or soon afterwards. This is why the name "viviparous" is sometimes used, as it means bearing live young, as opposed to laying eggs, which is more usual for lizards. The young are black in colour; They reach their sexual maturity at two years of age in males, and three years in females.
Common lizards are active during the day and spend the morning and afternoon (but not the intense heat of midday) basking in the sun either alone or in groups, going to find food when their body temperature reaches 30 degrees Celsius. They are good swimmers and will dive underwater when threatened. At night, and when startled, they will shelter beneath logs, stones and metal sheets. Common lizards hibernate from October to March. They will often hibernate in groups, and sometimes emerge for a brief time during warm spells.
In Britain, common lizards are protected by law under sub-section 9(1) and all of sub-section 9(5) of the Wildlife and Countryside Act, 1981. These prohibit the intentional killing and injuring and trade (i.e. sale, barter, exchange, transporting for sale and advertising to sell or to buy). This species is also now a priority species within the UK Biodiversity Action Plan and has associated conservation targets.
Emma Downie, CARG Secretary