Smooth Newt

Amphibians are cold-blooded animals that enter a state of semi-dormancy, similar to hibernation, during the cold, winter months in order to survive. It is called brumation, and they brumate in burrows, crevices and under logs where it is dark and damp. There are 7 species of amphibian in the UK: 2 frogs, 2 toads and 3 newts. The rarest of them all is the Pool Frog Rana lessonae, which is only found at a few secret sites following reintroduction programmes.

Adult Smooth Newt Lissotriton vulgaris that was found wandering around
between some of the UEA student accommodation.

Of the 3 newt species, the Smooth (Common) Newt Lissotriton vulgaris is the most widespread and common. It is much smaller than the Great Crested Newt Triturus cristatus, but is very similar to the Palmate Newt Lissotriton helveticus. In order to distinguish between Smooth and Palmate Newts, you have to look at the underside, as both sexes of Smooth Newt have white throats with dark spots, whereas Palmate Newts have unspotted pinkish throats. The males of all 3 newt species develop a wavy crest on their backs during the breeding season, however it is very low and smooth in Palmate Newts and much more developed in Smooth Newts.

Adult Smooth Newt found wandering around the UEA campus - returned to an area
with lots of fallen and dead wood for it to brumate (hibernate) under.

The reproductive strategies of the Smooth Newt are similar to those in the better known Common Frog Rana temporaria. The male Smooth Newts display to the females by vibrating their tails in a particular fashion and when she indicates that she is ready to mate, the male deposits a capsule containing his sperm in front of the female so she can pick it up with her cloaca. The female will lay her fertilised eggs individually, wrapping each one in an aquatic plant. A single female can lay 7-12 eggs per day and may produced 400 eggs in one season.

Immature Smooth Newt found brumating (hibernating)
underneath some deadwood in NE Hampshire

After about 2 weeks, the eggs hatch into larval form, first feeding off the nutritious contents of the yolk sac, before beginning to eat freshwater plankton, insect larvae and molluscs. Unlike frogs and toads, newts are carnivorous throughout their lives. The juvenile newts develop into smaller versions of the adults and leave the water after ~10 weeks. Smooth Newts take around 3 years to become sexually mature, and have an average lifespan of 6 years. Most adult and juvenile newts brumate over winter, emerging in the spring.


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