Adder

ADDER (VIPERA BERUS)

LOCAL BIODIVERSITY ACTION PLAN

Links to associated HAPs

Heathland

Ecology

Appearance
The adder is a robust snake with very distinctive markings, which make it easily recognisable in the field. These snakes can reach 90cm in length, however, they rarely exceed 65cm. Females tend to average 55cm (total length), males tend to be approximately 5cm smaller. Colouration is variable, though males and females differ sufficiently enough to be able to distinguish between the sexes. Both sexes have a distinctive dark zigzag pattern along their backs, with an associated row of dark spots along both flanks. The marking on the top of the head is shaped like a V, X or H. Females tend to be reddish brown whereas males tend to be a cream colour. However, confusion can occur when the males emerge from hibernation as they tend to be darker and resemble the females until their first moult.

Habitat
The adder can be found in a variety of habitats. These habitats include; heathland, moorland, coastal dunes, rough grassland, disused quarries and railway embankments. The adder prefers undisturbed habitat and is therefore rarely found in urban
areas unless they are associated with their preferred habitat.

Food
The adder is Britain's only venomous snake. However, the venom is designed to kill small mammals such as wood mice and is not particularly potent. The adders diet is mainly made up of small mammals such as voles, mice and shrews, though birds, lizards and frogs will be taken. Adders seem to combine two methods of hunting, the sit-and-wait and active hunting.

Lifestyle
Spring: Adders emerge from hibernation during March-April. Mating occurs April-May. Males slough their skin before mating occurs. Combat displays between rival males may be observed during the mating period 'the dance of the adders.

Summer: Females slough their skin for a second time before the birth of their young, which takes place between August-September.

Autumn: Adders seek out suitable frost free hibernacula i.e rabbit burrows in which to spend the winter.

Winter: Hibernating animals. Adders tend to hibernate for a period of roughly
five months (October-March). However, this can vary due to climatic conditions. Females tend to hibernate for a longer period of time.

Current Status

The adder or Northern viper (Vipera berus) has been recorded at five sites in Cheshire since 1995. It is considered to be of rare occurrence in the county although this may be due, in part, to a limited survey. Adders were recorded in the Cheshire region in the 1950s, although there seem to be only two records documented, neither of which make up any part of the post 1995 picture. Local unofficial sightings are commonplace but given that most turn out to be grass snakes (Natrix natrix), it is essential that these are looked into and the correct identification carried out. A Presence/Absence survey is required and results documented. Numbers and frequency can then be investigated in the future based on such results.

The most important records from Risley Moss LNR and National Trust properties on the Mid-Cheshire Ridge suggest that populations have survived in these areas for some time, and are relatively stable.

The adder is found in a variety and may crop up virtually anywhere, but dry grassland, scrub, heathland, moorland and open woodland are favourite. The vegetation cover and elevated nature of railway embankments may make this habitat the most important in terms of the widespread distribution of this species locally. Prey animals include viviparous lizard (Lacerta vivipara), slow worm (Anguis fragilis), various small mammals and the chicks of ground nesting birds. Therefore it is reasonable to expect two or more of the above at localities favoured by this species.

Adders are protected under the Wildlife and Countryside Act 1981 Schedule 5, Section 9, against intentional killing or injury. Trade in adders is also prohibited. The Adder was added to the UKBAP priority list in 2007.

Threats
* Disturbance and possible persecution by man.
* Loss of food animals further down the food chain.
* Loss of habitat due to human impact on recreational areas.
* Loss of habitat due to constructional development, agriculture and pollution.

How are we helping to conserve Adders in the Cheshire region?
* Cheshire and Wirral Amphibian and Reptile Group along with Cheshire Wildlife Trust, conduct recorder training events to encourage awareness of reptiles in the county, training on survey, identification and recording method for the more secretive species.
* The Risley Moss staff are aware of the group's activities, as are the National Trust staff responsible for the management of sites containing adders. Some survey work has been carried out and more work of this nature is planned.
* The Local Records centre, rECOrd, is producing a Provisional Atlas of Amphibian and Reptile sightings. Please send all sightings to rECOrd.

Objectives, Targets and Actions

The objectives, targets and actions to help conserve adders in the Cheshire region can be found on the Biodiversity Action Reporting System (BARS) along with full details of our progress so far.

How to find out more about Adders

BBC Wildfacts website - www.bbc.co.uk/nature/wildfacts/factfiles/279.shtml
Herpetological Consrevation Trust - www.herpconstrust.org.uk/

How can you get involved?

Join the Cheshire and Wirral Amphibian and Reptile Group, ask Julian Whitehurst (phone 01829 770797) for details.
Enter adder sightings and see the preliminary results on the HCT 'Add an Adder' project page - www.adder.org.uk

Contact details

LBAP Chair Julian Whitehurst
Phone: 01829 770797

References & Glossary
HCIL (1995): The Herpetofauna Guide.
Langton et al. (1993): A review of British Herpetofauna populations in a wider context, Joint Nature Conservation Committee.
English Nature (1994): Species Conservation handbook.
HMSO (1981): The Wildlife and Countryside Act (1981).
HMSO (1995): Biodiversity: The UK Steering Group Report, Volume 1.
HMSO (1995): Biodiversity: The UK Steering Group Report, Volume 2.