Wall lizard: rocking on the cliffs

The wall lizard (Podarcis muralis) is considered to be an introduced species to this country. It is a common species throughout most of Europe. It also occurs on Jersy where it may be native so it would be quite able to turn up here on the south coast and there are good populations in various pockets in Dorset, especially on the zig-zag paths in Bournemouth and in the limestone quarries of Purbeck and Portland. They are larger than our native common lizard and brown in colour but the male develops a beautiful mottled green streak along its back during the breeding season. This green colouring could lead to confusion with the sand lizard but their habitat requirements are so totally different that it should be obvious which is which! These are active little creatures, quickly gathering warmth from walls and rocks as they enjoy basking in the sun and they are quite confiding, only running off if directly threatened. Sadly, as with many ‘invading’ species, it seems that their presence may have a detrimental effect on populations of our common lizards so whilst they add to the diversity of our fauna there is a price to be paid

Grass Snake: the snake in the grass?

Over thirty years ago my wife and I were out for a stroll near our home and were returning along the roadside footpath that led towards our house. Stood in the road was a policeman who looked rather concerned and apprehensive; he was staring intently at the ground. As we approached we could see he was looking at a snake in the middle of the road! He obviously wanted to move it but was not at all sure whether he would survive the experience. I was pleased to be able to tell him it was not an adder, it was a grass snake. “Err, how can you be sure?” he asked. No V on the back of the head, no zigzag design down the back, yellow patches on the side of the head, too large to be an adder, wrong habitat – he was convinced, picked up the snake and moved it to safety at the side of the road! Although called the grass snake (Natrix natrix) this is not a snake that we often see in grassy areas, not because they are not there but because they are hidden. They are also nervous creatures that will generally slide away as soon as they detect you approaching. You most frequently see them in water, they are strong swimmers. They can be seen in lakes and ponds, including garden ponds, where they are both looking for food (they adore a fresh frog for lunch) or they are cooling off on hot days. They have become increasingly uncommon in the wild and large gardens with a pond and a good compost heap are now their preferred habitat where they stalk their prey and eat it alive which can be disconcerting if you hear the screams of a frog that is half inside a grass snake! Going back to the opening story, I have since found out that they often ‘play dead’ when under threat which is probably why it was lying in the road when approached by the policeman, there being no cover to ‘run’ to. I also understand that they can release a foul smelling liquid from their anal gland when handled and stressed so I reckon that policeman got away lightly don’t you?

Common Lizard: feeling tyred

I was leading a walk when we encountered a common lizard (Lacerta vivipara) on a discarded car tyre. Despite being very vulnerable and with over a dozen people staring at it it did not budge an inch. After a short while one of the party said “Is it tired?”. I explained that reptiles are cold blooded and as it was not a particularly warm day this lizard would be short of heat and so would be lethargic. The rubber tyre was absorbing some heat from the sun and the lizard was then absorbing heat from the tyre … then the penny dropped and I got the joke! Despite a ripple of laughter the ‘tyred’ lizard stayed put while many of us photographed it! The Dorset heath is home to all six species of indigenous reptiles and lizards tend to be a little easier to find as they are happy to sun bathe in more conspicuous places than snakes. The best time to find them is in the morning in spring. They can feel the ground vibrate as you approach and will make off into cover and safety unless you catch them cold like this one. The common Lizard is by far our most widespread reptile, as its name would imply. It is found across much of the country where the habitat is relatively undisturbed. Despite being common it is seldom seen unless you go looking for it. Our smallest native species of lizard, it eats small insects and spiders, it is not large enough to tackle anything bigger.

Sand Lizard: the sun worshipper!

There are some species that really are specialities here in Dorset. In fact, in the National Biodiversity Database there are more species recorded for the Isle of Purbeck than for any other area of similar size in the whole of the United Kingdom (this is what I am told, I have never checked it out!). This is primarily because of the Dorset heathland and the special animals and plants found there; some are very rare indeed and found only in this habitat. So it is with the sand lizard (Lacerta agilis). Along with the smooth snake they are nationally very rare creatures but are common here; they take some finding however! The sand lizard was once more widespread in Britain than just the heaths of Dorset, Hampshire and Surrey. They do have pretty specific habitat requirements; the soil must be sandy for them to be able to lay their eggs, they like extensive vegetation for shelter, a good supply of insects to feed on and sunny south facing slopes to warm up by sun-bathing. It has taken a lot of conservation effort to create areas ideally suited to it and the success of this has led to the species spreading further and further afield. I understand some are now being re-introduced to areas from where they have been lost. Being cold blooded they often use metal, especially corrugated iron, to warm themselves. The metal quickly heats in the sun and retains that heat and the lizards and snakes are quick to take advantage of it. However, until they are up to temperature there is little they can do to avoid the glare of the camera! During the breeding season the male sand lizard has a lovely bright green colouring on its flanks and both sexes have distinctive ‘eye-spots’ on their back. They are quite ‘chubby’ and so they are quite easily told apart from their duller, slimmer cousins, the common lizard. Like our other lizard species they are primarily insect eaters but the sand lizard is capable of taking larger prey and will even eat young of its own species.

Slow-worm? It is neither slow or a worm

The slow-worm (Anguis fragilis) is obviously not a worm at all, it is not even a snake. Despite its lack of legs it is a lizard and it can move very quickly when it needs to. It lives much of the time under ground and so legs would just get in the way and it can move much more effectively in its environment without them. It is because they live in the soil they are called worms of course. The slow-worm has smooth scales and is usually brown or grey in colour. In sunshine they can look an amazing combination of bronze and copper. The slow-worm is quite common but not often seen. Your best chance is to have a compost heap in your garden and then watch out for young slow-worms emerging. The adult slow-worm emerges from hibernation in March and spends a lot of time basking in the spring sunshine, usually in a well hidden spot in herbage, to gain warmth as they, like all reptiles, are cold blooded and need the sun’s rays to enable them to become active. They mate in May and the young are born in late August or even early September. Slow-worms are a gardener’s friend as they eat large numbers of slugs and snails. They have been known to eat small mice so this is quite a fearsome predator in the wild.  In my opinion the slow-worm is a stunningly beautiful reptile and they are certainly welcome in our garden.

Adder: summing it up

If there is one species of British wildlife that will strike fear into people it has to be the adder (Vipera berus)! Not only is it a snake (and many people love to hate snakes), it is a poisonous snake and uses its venom to kill its prey. I do not pretend the adder is a harmless creature and I treat them with respect as anyone should, but adder bites are rare and, whilst uncomfortable, certainly not serious.  It is uncontrolled dogs that are most likely to be ‘innocent’ victims of the adder and I am not even sure that that is at all common either. The adder is a very shy creature and can detect approaching people by the vibrations in the ground and so they generally slide away in to nearby cover at the first hint of danger approaching. Only if accidentally trodden on, or foolishly handled, are they likely to bite. Although as common here in Purbeck as it is anywhere in the UK the truth is that the adder is now far from common even here and seems to be in serious decline. Research shows that as the adder’s natural habitat becomes fragmented by roads and development so populations are forced to interbreed and the gene pool is becoming very weak and the species is dying out. Efforts are under way to try and correct this but it will take time before enough can be captured and relocated in to other colonies before we know if the programme is successful. Not only can they be found on the Purbeck heaths you may also find them basking on sea cliffs, grass downland, south facing embankments and other ‘wild’ places. To many the news of the decline of the adder will be welcome but it is a truly beautiful creature with striking markings down its back and dark V on the back of its head To me the loss of the adder would be a tragedy. I rarely see one but when I do I never fail to be thrille; they are just special!

Smooth Snake: a real smoothie

All of our three native British species of snake are now scarce to say the least but the smooth snake (Coronella austriaca) is nationally rare. In Dorset, however, thanks to the large area of remaining lowland heath which is now a protected habitat they are actually quite well established. Despite this they are rarely seen as they are very shy and secretive creatures and you are very fortunate if you encounter one. It is a small, slender snake with what I consider to be a very gentle face! They are not, however, gentle creatures and are quite capable of killing lizards and slow-worms as part of their diet. They are constrictors squeezing their victim to death before swallowing them whole. They are not venomous and are totally harmless to human beings. As their name implies, their skin is smooth to touch as the scales lie flat and this, as well as their size and pale brown blotched skin, tells them apart from the other two species. That said, they are a protected species and should not be handled without a licence to do so as they need to be treated with care to avoid injury. It is such a shame many people dislike, or are even frightened of, snakes. They are truly awesome animals in my view.