INTRODUCTION

Amphibian and reptile (herpetofauna) recording in the county has gained momentum in the nineties and with the development of an electronic database these records can be used to produce distribution maps at a 1 km squared resolution. Over 3500 records are in the Warwickshire database with new ones being entered all the time. Each record is a six figure ordnance survey reference and is not technically a ‘site’, as there may be several records for one specific ‘site’. The mapping facility enables any records within a 1 kilometre square to be summated in order to produce a series of distribution maps of Warwickshire’s herpetofauna.

The UK supports six native species of amphibia and six native species of reptile. In Warwickshire there are four amphibian species and four reptile species (asterisked).

Amphibians		Reptiles
Common Frog (Rana temporaria)*		Grass Snake (Natrix natrix)*
Common Toad (Bufo bufo)*		Adder (Vipera berus)*
Natterjack Toad (Epldalea calamita)		Smooth Snake (Coronella austriaca)
Smooth Newt (Lissotriton vulgaris)*		Common Lizard (Zootoca vivipara)*
Palmate Newt (Lissotriton helveticus)		Slow Worm(Anguis fragilis)*
Great Crested Newt (Triturus cristatus)*		Sand Lizard (Lacerta agilis)

The Natterjack Toad, Sand Lizard and Smooth Snake are rare species and are confined to specific habitats such as sand dunes and lowland heath elsewhere in Britain.

The Palmate newt (Triturus helveticus), despite being frequently recorded in Wales, West England and Scotland has not been recorded in Warwickshire after the second World War, although we do have unconfirmed reports from Nuneaton and Sutton Park for this species. In the 1901 Victoria County History of Warwickshire the Palmate newt is described as 'very common and abundant on the oolitic hills of Gloucestershire and the near parts of Warwickshire.' The writer mentions that the further from those districts the rarer it becomes and there are no records from North Warwickshire. More survey work, especially in the extreme south of the county around the Warwickshire/Gloucestershire/Oxfordshire border is needed to confirm the Palmate newt's definite absence from the county.

Due to their secretive nature, reptiles are under-recorded compared to amphibians which are relatively easy to see during their spring breeding season in ponds and other water bodies. 74% of the records in the database are for amphibians, compared to a mere 26% for reptiles. Surveying for reptiles is very weather-dependent, with reptiles preferring to bask when the air temperature is between 10 - 20 degrees Celsius with no wind. Ideal conditions within this temperature window are sunshine after a rainy spell or an overcast day, when the sun is trying to break through the clouds.

Reptiles and Amphibians

Reptiles are easily recognised by their dry, scaly skin whereas amphibians skins are moist and lack scales. Unlike warm-blooded birds and mammals, reptiles and amphibians have variable temperatures and gain heat by basking in the sun and live close to the temperature of the air or water that surrounds them. All amphibians need fresh water in which to spawn or deposit their eggs whereas reptiles need warm sites to deposit their eggs or retain the eggs inside the body and give birth to live young. Reptiles and amphibians play an important part in ecological communities and are valuable indicators of environmental change.

Reptiles and Amphibians in Decline

Numbers of reptiles and amphibians continue to decline. The threats facing them include habitat loss through urbanisation, intensive agriculture, habitat degradation, as well as changes in land management, pollution and persecution. Ponds have been filled in and are not created and important retile breeding sites have been knowingly or unknowingly destroyed. Unusual mass mortalities of frogs have been reported and lizards can build up a high level of insecticides in their bodies which has a toxic effect, as well as depriving them of their insect prey.