Only one species of newt left in Ireland

I came across a newt the other day in a shallow garden pond.

I hadn’t seen one for a while and I’d forgotten what extraordinary creatures they are — little dinosaurs left over from the Jurassic.

There’s only one species of newt in Ireland, though there are several in Britain and even more on the Continent. It’s sometimes called the smooth newt or the common newt. Its scientific name has changed as well. It used to be Triturus vulgaris but now it’s Lissotriton vulgaris.

Ireland and Britain have their own sub-species, the doubly vulgar Lissotriton vulgaris vulgaris.

They are about 10 centimetres long and during most of the year it’s quite hard to tell males from females. They are both brown or dark olive coloured with a long paddle-like tail to help them swim rapidly to catch prey. But the male has a single black line down its spine, while the female has two parallel black lines either side of her spine. And, if you get a very close up view, you may notice that only the male has fringed toes.

But during the breeding season, which is now, mature males develop a spectacular livery that makes them unmistakable. They go much darker and grow a long, wavy crest along their spine and tail. Dark spots appear all over their bodies and their undersides turn orange, brightest on their throats.

The male displays all this finery in front of a female, with much waving of his new crest, and eventually deposits a capsule containing sperm in the water. This is called a spermatophore. The female then has a lot of complicated manoeuvring to do before she can pick up the capsule in her cloaca. Fertilisation is then internal, which is quite unusual among amphibians.

A couple of weeks later, when the water temperature is right, she starts laying eggs. They are single eggs, not great clumps like frog spawn, and usually deposited on the underside of the leaves of water plants. She lays 7 to 12 a day but will do this for some weeks, producing a total of up to 400 in a season.

The eggs hatch into tadpoles two or three weeks later when the water has warmed up a bit more. The tadpoles are nourished by their yolk sacs for a few days, rather like fish fry, and then start eating freshwater zooplankton before graduating to bigger prey. Large tadpoles and adult newts mostly eat insect larvae, molluscs and fish fry. Newts are totally carnivorous from the word go.

As the tadpoles grow their lungs develop, their feathery external gills shrink and they start to develop legs. After about 10 weeks they leave the water as small adult newts, though a few late-hatched ones may over-winter as tadpoles.

Most newts hibernate on land in a warm, damp crevice in a rock or a rotten log. On land their skins have a soft, velvety feel. They spend about two-thirds of the year as land animals and one-third, or a little bit more, in the water. They don’t become sexually mature until they are about three years old and their life expectancy is six years.

In Ireland it is an offence to capture, kill or sell a newt, including a newt tadpole, without a licence. For practical purposes this means that if you have a garden pond and you have an ambition to have newts in it and not to break the law you’ll have to lure them in from the wild. They like fairly shallow water with plenty of water plants and prey animals in it and the pond must have gently sloping edges to allow them to clamber in and out.

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