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Reptile Ramble - Isle of Arran Wildlife Festival
More Inland Walks
A
ramble into Glen Rosa in Brodick with a chance of a closer look at
adders, slow worms and common lizards, weather conditions permitting.
Suitable for children over 14.
Dates 2010 |
Times |
Price |
| Wed 12th May |
13.30 -17.00 |
£2 per person |
| Max 12 people |
Meet |
Glen Rosa Campsite (NS001376) |
Organiser |
|
Wheelchair access |
No |
Booking required |
Tel: 07501 337532 |
What to bring |
Walking boots, waterproof jacket and trousers, packed lunch and a drink |
The adder is the only venomous snake native to Britain. Adders have the
most highly developed venom injecting mechanism of all snakes, but they
are not aggressive animals. Adders will only use their venom as a last
means of defence, usually if caught or trodden on. No one has died from
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.
Name
Adder (Vipera berus)
Lifestyle
Habitat
Adders are relatively common in areas of rough, open countryside and
are often associated with woodland edge habitats. They are less
inclined to disappear into the surrounding undergrowth when disturbed
and so are probably the most frequently seen of the three British
snakes. The best time to see them is in early spring when they emerge
from their hibernation dens. By mid April, the males have shed their
dull winter skin and are ready to mate. There is a lot of frenzied
activity on warm days, with males looking for females and occasionally
wrestling with other males for supremacy. The 'dance of the adders' was
thought to be a mating display, but it is a larger male attempting to
drive off a smaller one. The snakes writhe around each other in an
impressive way, often covering the ground at great speed.
Breeding
Following mating, females seek out a suitable place to give birth,
often travelling over 1 kilometre from the hibernation site. Births
take place in late August / early September. Unlike most reptiles,
adders do not lay eggs. Young snakes are born about the size and shape
of an earthworm, but a perfect miniature of the adult snake.
Development
During the autumn, adult snakes follow scent trails left by other
adders to find their way back to the hibernation site, which is often
used by many snakes over several years. The young adders tend to
hibernate in the area where they were born. Their survival largely
depends on the severity of the weather in the following winter.
Diet
Adders usually eat small rodents, such as the short-tailed vole. They
will also eat lizards, frogs and newts, and have been seen taking young
from the nests of ground nesting birds. When hunting, adders strike
swiftly at the prey, injecting a lethal dose of venom. They then wait
until the prey dies before starting the often lengthy swallowing
process. Like all snakes, adders eat their prey whole, their teeth are
designed to grip the prey as it is swallowed. Their jaws are linked by
extensible connective tissue so each of the four main bones can move
independently. This means they are able to swallow items much larger
than the width of their head. The lower ends of the ribs are not joined
as in most animals and can also open out considerably. The adder's
digestive fluid is amazingly powerful and will digest the flesh and
bones of their prey almost completely. Only the hair and teeth of
rodents pass through intact.
Threats
Young adders are threatened by a variety of predators, including birds
of prey such as the common buzzard and sometimes adult snakes. Others
may be killed and eaten by rodents while in hibernation. Adders are
protected by law against being killed or injured through human
activity.
Identification
Most adders are distinctively marked with a dark zigzag
running down the length of the spine and an inverted 'V' shape on the
neck. Males are generally white or pale grey with a black zigzag.
Females are a pale brown colour, with a darker brown zigzag. But some
adders are entirely black and can be mistaken for some other species.
How we manage our woods
Most of the woods managed by the Forestry Commission are
suitable for adders. The way we manage the woods - cutting down older
trees and planting young trees - provides excellent habitat. For the
first 10 years as the young trees grow, adders can build up large
populations unseen. Then as the tree canopy closes overhead, the snakes
seek out the light and warmth that is available at the woodland
edge.
info from the forestry commission. |