Reptiles and amphibians

Adders are Britain’s only venomous snake; their bites are painful and can be potentially serious, but adder bites to humans or dogs are very rarely fatal.  There have only been around ten recorded cases of death from adder bites in the last 100 years, and most bites occur when the adder has been disturbed or deliberately antagonised.  Their venomous bite is used to kill prey (small mammals, amphibians, reptiles, and birds) which they swallow whole.  They are found in open habitats with plenty of sunshine, such as heathland and moorland, rough grassland, open woodland, and coastal areas; they are rarely found in gardens.  The majority of adder records come from Dartmoor, Exmoor, the Pebblebeds, Haldon and the Bovey Basin Heaths, but there are also scattered records from the rest of Devon.

Adders are 60-80 cm long, with a stocky body shape, unlike the longer, more slender grass snake.  They have a dark zigzag along their backs; males are grey with black markings while females are brown or coppery with dark brown markings.  Completely black (melanistic) adders are common in some areas. 

Adders emerge from hibernation in late February-early March and mate a month later.  The males compete with eachother, in the ‘Dance of the Adders,’ rising up with their bodies twisted together in an attempt to force each other to the ground.  The females give birth to 6-20 live young in August and September. Adders hibernate, often in groups, in frost-free locations such as south-facing, dry high ground with plenty of cover, or in disused mammal burrows.  They can hibernate from October to February, depending on local conditions.

Adder populations are under threat nationally; Make the Adder Count, a long-running citizen science project set up by ARG UK, found that 90% of the sites surveyed had small populations, with fewer than 10 adders.  On average these small populations were declining, and only 10% of sites had large populations, that were stable.  If these trends continue over the next 10-20 years, adders will be restricted to just a few sites in the UK and will be at risk of extinction.

Habitat

Common Toads are slightly smaller than Common Frogs, crawl rather than hop, and have rough, warty and relatively dry skin. The skin of adults and tadpoles contains toxins, making them distasteful to predators.

Toads lay eggs in the early spring (often a few weeks after frogs) in waterbodies such as ponds, ditches and lake. Toad spawn is easily distinguished from frog spawn as it forms long strings (not clumps). Toads have a strong migratory instinct and will follow the same route back to ancestral breeding ponds each spring.

After the breeding period (a few weeks) adult toads migrate away from ponds. They live in moist, shady well vegetated areas with lots of leaf litter, logs, rocks and dense vegetation which provides cover and food. They eat insects, slugs, snails, spiders and occasionally smaller amphibians. Like frogs, they’re mainly active at night. They spend the winter buried in mud, under compost heaps or among deadwood.

Population

The toad population has declined nationally, especially in the southern half of Britain. The main reason is thought to be due to fewer ponds and other water bodies. Toads are widespread across Devon but are far less common than frogs. They are listed as a Devon Special Species as they are near threatened and (like Great Crested Newts) are a great flagship species for pond conservation.

Habitat

Adult Great Crested Newts are easily recognised due to their large size (they can be up to 17 cms), bright orange underside with black blotches and an impressive, jagged crest along the back of the males.  

Great Crested Newts breed in around March to June. They lay eggs in waterbodies, preferring large ponds or small lakes with abundant weeds, a neutral pH, and no fish. They’re often found in flooded mineral workings, where huge populations can develop. However, they can also breed in smaller ponds (including in gardens) and ditches. Females lay around 200 eggs, wrapping each one individually in the leaves of pond plants.

Outside the breeding season they can be found outside waterbodies. Like toads (and other amphibians) they need moist, shady well-vegetated areas with lots of leaf litter, logs, rocks and dense vegetation that provides cover and food. They can therefore be found in a range of habitats such as woodlands, dense hedges, scrub, tussocky grasslands and field margins, in rural and urban areas.

Great Crested Newts are thought to be able to travel an average of 500 m from a pond, but have been known to travel further distances, possibly up to 1.7 kms depending on habitat continuity and barriers such as large roads.

Like other amphibians they are carnivorous and will eat whatever they can find including worms, slugs, insects and tadpoles. They’re largely active at night, spending the day at the bottom of ponds or in vegetation. Great Crested Newts don’t hibernate but spend the winter under rocks or log piles, in compost heaps or buried in mud. However, in warmer weather they may come out to feed. 

Population

The Great Crested Newt population has shown huge declines in range and abundance over the last century and they’re strictly protected under British and European law.  

Devon is on the edge of their UK range, and they’re mainly found in the south and east of the county. However, they have been re-introduced to several locations in the north and west, including Braunton Burrows. They’re listed as a Devon Special Species as the majority of Great Crested Newts are found outside protected sites and as they (like toads) are a great flagship for pond conservation.