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Oxfordshire has five native species of amphibian;
The Natterjack Toad, Bufo calamita, is not found in Oxfordshire. A few non-native species have escaped and in some instances have become naturalised, but they are rarely encountered.
The Common Frog and Common Toad are thought to be widespread throughout Oxfordshire although their exact numbers and distribution are not known. It is suspected that their numbers are declining.
Smooth Newts are the most common and widespread of the three newt species, with the Palmate being more restricted and usually found in areas with more acidic water. The larger Great Crested Newt, although heavily protected, is in fact not as rare as most people would think. Britain is home to a large percentage of the world population and it is commoner than the Palmate Newt in Oxfordshire.
Amphibians are under-recorded. Most ponds support at least one breeding species with Frogs probably the most obvious species. Newts, which are more secretive and strictly nocturnal, are less recorded. Also, because the two small species (Smooth and Palmate) can be difficult to tell apart, their precise distributions, especially the Palmate, are not accurately known. During the breeding season male Palmate and Smooth newts are easily distinguished but the females are very similar. Male Smooth Newts are often misidentified as Great Crested Newts by inexperienced observers because they too have a well developed crest in the breeding season.
(You should find these useful if you don't have an ID book.)
These pictures clearly show the difference between the Common (Smooth) Newt and the Great Crested (Warty) Newt.
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Great Crested Newt (63KB JPG image) plus picture of belly. |
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Great Crested & Smooth Newt (61KB JPG image) |
Frogs, and to a lesser extent toads, are more noticeable because they are very vocal and noisy as they gather in the early spring to breed. Frogs will spawn in almost any pond and are familiar garden animals. Outside the breeding season most frogs and toads live away from the water. Toads prefer larger water bodies for breeding and during the summer months they are often seen in their terrestrial phase.
Compared to frogs and toads the three species of newts spend more of the spring and summer months in water; they also breed later and over a longer period. During the day they may be seen briefly coming up for air before quickly dropping to the bottom of the pond again. They are more active at night - patrolling for mates or searching for food.
Like frogs and toads, newts also spend a great deal of time feeding on dry ground. All these amphibians are predominantly nocturnal feeders and are usually inactive during the day unless they are disturbed. Frogs, toads and newts usually overwinter in terrestrial habitat. Some frogs and newts, however, will hibernate in mud at the bottom of ponds. Many human encounters with newts occur on land when they are found hiding under stones or logs, or down drains. These and similar locations are good places to live outside the breeding season when the animals are not in the pond.
Amphibians do best in areas with;
The loss or degradation of terrestrial and aquatic habitats has serious consequences. Gardens can provide alternative breeding and living habitat, especially for the Common Frog and Smooth Newt. The other species generally prefer a more natural landscape with the Great Crested Newt preferring to live in, or close to, woodland.
Water bodies, such as ponds, are essential for breeding. The eggs are laid in the water and the larvae (tadpoles) are aquatic. The location and type of the water body together with the water quality and chemistry will determine which species breed. Predation of eggs and larvae by fish or water birds are often critical factors. Great Crested newts, for example, do not usually breed successfully if fish are present in a pond. Water birds (ducks etc) can damage or destroy plants (by eating them) that provide essential egg laying sites and protective cover for larvae.
