The Palmate Newt (Triturus helveticus) is a small newt common throughout the UK.
The Palmate newt is a relatively small species, males reaching only about 8.5 cm and females 9.5 cm. The base colour of both sexes is olive-green or brown, a dark mask-like line runs across the head through the eyes; males and some females have a dark spotting on the back. Sometimes confused with the Smooth Newt, the palmate does not have the spotted throat of the smooth newt, but both sexes have a yellow or pale orange belly that can show some spotting.
Males have webbed hind feet and a low, smooth crest along the back that continues into a slightly higher crest on the tail ending in a thread like tip during the breeding season of April - May. Males can also have enlarged cloacal regions when close to breeding due to the spermatophores pressure exertion on the cloacal tissue.The crest and filament become less obvious and may disappear at other times when they become terrestrial. Males also have marked dorsolateral ridges, giving them a rather square cross-section. Females grow to 10cm (4in) and males to 8.5cm (3.3in). During the breeding season they are active during the day as well as night, but outside this period activity is restricted to rainy or humid nights.
Habitat, reproduction and feeding habits
It lives in ponds, lakes, canals, marshes, forests, pasture or agricultural land, sometimes in acid pools on upland moorland or coastal areas. It spends the breeding season (February to May) in water laying 100 to 300 eggs which hatch into larvae in about 2 to 3 weeks and then metamorphose after a further 6 - 9 weeks. In colder areas the larvae often over-winter in the water and then metamorphose the next year. They become sexually mature in the second year, but neoteny is also known to occur in this species. Adults hibernate on land under logs and stones between November and March, or more rarely in water.
They feed on invertebrates, small crustaceans, planktonic animals, daphnia and also frog tadpoles. They are also known to display cannibalistic tendencies and they can live for up to 10 years.