Adder
Description
Adders are relatively short and robust with large heads and a rounded snout. Their red–brown eyes have vertical elliptical rather than round pupils. They have a characteristic dark zigzag running down the length of the spine and an inverted "V" or sometimes "X" shape on the neck. Males are generally greyish with a black zigzag; females are a pale brown with a dark brown zigzag; however, some adders can be completely black and are mistaken for other species.
Behaviour
Males shed their old winter skin and are ready to mate by mid-April when their frenzied activity may be witnessed on warm days as they compete with other males for supremacy in getting the females attention. The "dance of the adders" was once thought to be a mating display between a male and a female but it is actually a larger male confronting a smaller male. The snakes writhe around each other, often covering the ground at considerable speed.
Size
Length: 50–65 cm. Females are larger than the males.
Where to see them
Fairly common in areas of rough, open countryside and woodland edge habitats.
Adders have been recorded on the following SWT reserves: Carsegowan Moss, Feoch Meadows, Flanders Moss, Grey Hill Grassland, Knowetop Lochs, Largiebaan, Loch of the Lowes.
When to see them
Relatively easy to see particularly on dry, sunny days. Early spring when they emerge from hibernation is probably the best time to look for them.
What they eat
They eat lizards, amphibians, small mammals and nesting birds using venom to immobalise their prey. After striking, they allow the venom to take effect before returning by using their keen sense of smell to find the body.
Status
Protected under the Wildlife and Countryside Act 1981 from being killed, injured or sold and is a UK BAP Priority Species (new list).
Distribution
Widespread throughout mainland Britain but absent from Ireland. They occur throughout Europe with the exception of the Mediterranean islands, and across Russia and Asia through to Northern China. They are one of the most widespread species of snake.
Threats
Habitat loss, fragmentation or inappropriate management.
Fascinating facts
The only poisonous snake native to Britain, adders have the most highly developed poison-injecting mechanism of all snakes. Though not naturally aggressive and only using their poison as a last means of defence, they are quick to defend themselves if molested and can move with lightning speed. No-one has died from an adder bite in Britain for over 20 years. With proper treatment, the worst effects are nausea and drowsiness followed by severe swelling and bruising in the area of the bite. Most people who are bitten were handling the snake.
Treat adders with respect and leave them alone.