Common toad

Common toad by Philip PreceyCommon toad by Philip Precey

Bufo bufo

The common toad is a welcome visitor in gardens because its diet includes pests such as slugs. It is distinguished by the brown, warty skin on its back and a blunt nose. During the day the pupils of its eyes are horizontal slits against a beautiful gold/bronze iris. At night when it is most active, the pupils expand and become circular. Less agile than frogs, toads tend to walk rather than hop but usually spend daylight hours sedentary, tucked under a suitable log or stone or buried in soft earth.

The warty skin contains glands which, when the toad is threatened, secrete a distasteful and odorous toxin. It will also extend its legs and puff itself up to look as large as possible to deter predators. Tadpoles also have the toxin which makes them less likely to be eaten by fish allowing them to breed successfully in ponds where fish are present. However tadpoles and toadlettes can still fall prey to beetles and dragonfly larvae which pierce the skin to suck out body fluids so, avoiding the worst of the toxins.

After emerging from hibernation in the spring adult toads move, often en masse, to their breeding ponds. It is at this time of year when the adverse effects of habitat fragmentation can be seen on this species. Where roads have been built between hibernation sites and breeding sites, casualties can be high. Known, important sites are marked with road side signs and at many of them teams of volunteers turn out every year to help the toads cross the roads.

Toads prefer deeper water for spawning than frogs so tend to favour larger ponds. A double string of eggs is laid in a rope through aquatic vegetation. A female can produce up to 5,000 eggs each year but very few of these eggs will survive to become mature, breeding toads. It will take between three, for males, and five years, for females, to reach breeding age. Toads have been known to live for 50 years in captivity, but in the wild, life expectancy is more likely to be about ten years.

The loss of large ponds in the countryside is one factor having a negative impact on toad numbers. As well as being lost through pollution and infilling, once suitable breeding ponds may be lost as Britain experiences longer dry spells and water bodies dry up before the toadlettes are ready to leave the water. On top of loss and fragmentation of habitat, toad populations have been hit by disease in the last 20 years. Firstly ranavirus, or red leg disease and now the threat from the fungal chytridiomycosis or chytrid. Disease is spread by material, plant or animal, being moved between ponds so it is very important not to move spawn or aquatic plants about. It is especially important not to introduce captive animals to ponds in the wild. This may be how the devastating ranavirus arrived in Britain.

Toads often hibernate in woodland and are fond of leaf litter as a shelter taking refuge in piles of leaves or bonfire heaps in gardens. Unfortunately this exposes them to the risk of incineration, so if garden clippings must be burnt rather than used to make habitat piles, the best course of action is to make the pile immediately before burning to avoid wildlife moving in. Otherwise check any heaps carefully before setting alight.

Suffolk Wildlife Trust works alongside Suffolk Amphibian and Reptile Group to promote understanding and conservation of all herpetofauna. Report any sightings via the recording page or send them directly to the County Recorder, Rosie Norton.