Grass Snake Natrix natrix
A small and slowly declining snake, which can vary in colour from greens, greys, browns and, occasionally, black. Its most recognisable feature is the collar behind the head which can be yellow, orange or white.
Conservation status in Norfolk
Grass snakes have become scarcer. There are still some areas where they are locally abundant, but nationally they are in decline.
How to help
Create a compost heap in a sunny location. Not only will this help you recycle green household waste but it will create a suitable egg-laying site for grass snakes.
Grass snake, Julian Thomas
Grass Snake playing dead, Darren Williams
Grass Snake in water
Information on the Grass Snake
How to recognise
Body colour can vary from green to grey to brown or even black. However, the most distinctive characteristic of this snake is a yellow, orange or white collar immediately behind the head.
Where to see
Open woodland, heathland, fens and meadows are all suitable habitats for grass snakes. They seem to inhabit sites close to water and people may find them visiting their garden pond. A good place in Norfolk to view a grass snake would be one of Norfolk Wildlife Trust’s broadland sites, for example NWT Hickling Broad and NWT Upton Broad and Marshes.
When to see
From October to late March grass snakes hibernate, usually communally in a mammal burrow. The female will lay her eggs in June or July, with the young emerging from late August through September (if it has been a cool summer eggs may not hatch until October).
Did you know?
Grass snakes are primarily associated with water. They swim well, feed mainly on fish and amphibians, and can remain underwater for well over half an hour if disturbed.
Related questions
How can I attract reptiles to my garden?
Of the four species of reptile occurring in Norfolk only two,the grass snake and slow worm are likely visitors to your garden.
The other two species, the adder and common lizard, are creatures of more open and undisturbed habitat such as heathland and only rarely visit gardens. Even then it is likely that the garden in question adjoins an area of suitable countryside.
If you wish to attract slow worms or grass snakes you will need to keep some areas of your garden undisturbed and uncultivated. Unkempt areas of long grass, wild areas of scrub and hedgerow with plenty of undergrowth and other nooks and crannies, such as provided by log piles, would be ideal. A compost heap is particularly useful since both slow worms and grass snakes will inhabit these either to feed on the abundant slugs and worms or to lay their eggs. A garden pond is also of great value to grass snakes because it provides ideal habitat for them to hunt frogs and newts.
If you are lucky enough to see any reptiles in your garden you should report sightings to
the National Amphibian and Reptile Records Scheme (NARRS) so that distribution and population trends can be monitored.
What reptiles can I see in Norfolk?
Four of the six UK reptiles occur in Norfolk the exceptions being the smooth snake and the sand lizard which are largely confined to the heathlands of southern Britain.
The reptiles you can see are:
Adder. The adder is a quite common species in Norfolk and can sometimes be disturbed from areas of heathland, dune systems or woodland glades especially during early spring when they are reviving from their winter hibernation or are engaged in courtship.
Grass Snake. These are quite common, especially on or near wetlands where they will hunt for frogs, newts and other such prey. Broadland has a large population and the best time to see them is on warm early spring days.
Slow-worm. These ‘legless lizards’ are not very common in Norfolk. They do occupy a variety of habitats but prefer grassy meadows, woodland margins and open fields. They can also sometimes be found in gardens.
Common (or Viviparous) Lizard. These reptiles are very common and widespread in Norfolk. They are best looked for on sunny days basking on fenceposts and other exposed objects.
What is the difference between an adder a grass snake and a slow worm?
THE ADDER
The adder is found on heathland, dry commons and in sunny clearings in woodland. The basic colour is variable, ranging from off white through to brown, but whatever the colour the distinguishing feature is the wide, dark zigzag stripe running along the back. This stripe is usually flanked by a row of spots running along each side.
The adder has a distinct "V" or "X" shaped marking on the head and the eye has a pupil with a vertical slit. Adders appear quite chunky and males can reach a length of up to 60cm, females up to 75cm.
GRASS SNAKE
Grass snakes are usually found in wetland habitats. The basic colour is olive green and there is a distinct yellowish/off-white and black collar around the neck. There are dark side markings along the whole length of the snake.
The grass snake has an eye with a round pupil. The grass snake has a quite slim appearance and is the largest indigenous UK reptile. Males can reach a length of up to 100cm and females up to 130cm.
SLOW WORM
Slow worms are very secretive creatures but can be found in a variety of habitats including gardens.
The slow worm has a colour which varies from light or dark brown through to brick red but they are far less well marked than the adder or the grass snake.
Males and females show marked differences when fully grown. Females very often have a thin dark stripe running along the length of the back and the flanks are speckled and striped with dark brown or black. Adult males are more uniform in colour and occasionally have very distinct blue spots. Length of both sexes is between 40 - 45cm.
What is the gestation period of a grass snake?
grass snakes mate during April after they come out of hibernation in March. The female will then lay her eggs in June or July in a warm place where the heat will allow the eggs to develop. This takes around 10 weeks and the young will hatch from late August through September. If the weather has been particularly cold then hatching may be delayed until October.
Surveying amphibians and reptiles - How can I find out what species are present in my garden?
Unless you live adjacent to a suitable wild habitat or have a large garden with a corridor to an area of open country, you are unlikely to have amphibians or reptiles in your garden. Perhaps the most likely will be grass snakes, which may feed in garden ponds or lay eggs in compost heaps.
However, if you live close to a wild area, amphibians and reptiles may sometimes use your garden for feeding and breeding or as a corridor between more favoured habitats. Techniques for surveying amphibians and reptiles in your garden is essentially the same as for larger spaces. You can tailor the techniques to suit the size and nature of your garden.
Use sample garden amphibian and reptile survey form g.