Wall Lizard or Podarcis Muralis
A strikingly marked and agile animal the wall lizard is represented by having many Different species and variations. Even within a local population colour morphs vary considerably causing possible confusion to the human observer. Here in Bournemouth many differing colour morphs occur, perhaps different stock has been introduced regarding different sub species, which have now interbred.
It is not known when the species first occurred here in Bournemouth, but certainly in the 1970's a male was collected from Bourne valley this is not exactly the cliff top. It was taken as a male sand lizard along with other specimens and stored at The Bournemouth natural science society in a jar of formaldehyde. It was not until much later that they were officially recorded. It is of course possible for these types of lizard to naturally colonise islands. They naturally occur on the channel islands and northern France, and the colonies That do occur seem to be mainly on the south coast of England No proof has been Found that would indicate that that our animals are direct descendants of these Animals. Some colonies though are certainly more reminiscent of them, such as the Portland colony.
In Bournemouth they are concentrated in two large sections of the cliff top and cliff face, the longer stretch is around the Poole chines, and the other area is between Boscombe and Southbourne cliff; the later colony perhaps displaying more variation. A very active species, it does not hibernate like our natives but remains semi-active during the winter months in sunny weather. The south facing aspect of the cliff Habitat resembles that of a Mediterranean climate. Along with many continental Species of plants and insects, our traditional heathland habitat of the cliffs is disappearing.
This is a purely natural occurrence, and even if one of our protected reptile species i.e. the sand lizard is replaced, it of no great loss, as the cliff habitats are small in comparison to the much larger blocks of heath in which that species does better in terms of genetic variation and cooler winter temperatures. No proof has been found to suggest that one species is out competing another. There is proof though that the warmer climate and warmer winters are affecting our native species especially in terms of hibernation success, mainly in regards to the common lizard.
Western Green Lizard - Lacerta Biliniata (Viridis)
This continental species has been living around the Boscombe and Southbourne Cliff tops for some years. I first saw a female in 1999. There was a report from 1996 of a dead huge all green lizard on the Portman ravine steps, but the body had gone by the time I got to the scene. Not surprising as the area is very busy with people and corvids.
There has since been reports from beach hut owners of large green Lizards being seen as far back as the 1970's. Nobody has admitted to releasing them, although there are suspicions. It may well be that several introductions took place each with varying degree of success. It would seem that there is a mix in genetic make up; this could reflect the captive breeding or natural wild breeding within the colony of the different released animals. There could may well have been taints from another species the eastern green, lacerta triliniata, as I personally have Had seen several individuals that correspond to that species but have now died out During hard winters.
Our climate is certainly favouring the smaller and brighter animals that are more reminiscent of the true north western variety. Green lizards hibernate like the sand lizard of which they are related to, but do not Specialise in sand egg laying as that species does. They are much larger than sand lizards, attaining lengths of 40 cm, but as I suggested the size is shrinking as natural selection kicks in. The smaller ones seem to have brighter colouration and the males have brighter Blue throats or in some cases heads. The larger specimens had white throats and Heads, with thicker snouts than back of head, similar to trilineata. Some individuals are very small, not much bigger than a very big sand lizard.
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