Lissotriton vulgaris - The smooth newt

 

Written by Lachlan Royle - BSc Ecology and Conservation Student 

The Smooth Newt: This small amphibian is one of the UKs most abundant and goes by many names such as the European newt and Common Newt. It is one of three newt species native to the UK alongside the palmate newt of the same genus Lissotriton, and the Great crested newt of genus Triturus. Of the three species the smooth newt is the only one not actively in decline, thought to be due to its great abundance in garden ponds and pools. It is remarkably widespread with records from the northernmost to southernmost tips of the country. 

Behaviour 

The smooth newt like many of its other family members are generally rather drab looking throughout the majority of the year whilst also being largely terrestrial based. However when breeding season arrives males transform with a large undulating crest along their back stretching from head to tail tip. Courtship between smooth newts can be dramatic and brief, with mating season generally only lasting for a few weeks. The courtship process involves males harrying or chasing after females in order to attempt a successful spermatophore transfer. Other males will actively try to break up mating attempts between individuals in order to increase their own chances of a successful mating process. This form of courtship is most similar to a lek like you may observe between rutting stags, with the intensity of the male conflict dependent on female availability. 

Smooth newts diets are entirely carnivorous with earthworms and other small invertebrates making up the majority of  their diet, however they are not unknown to be cannibalistic with instances of individuals consuming eggs of their own species. Being rather slight in size they are a source of food for many different animals including fish, waterbirds, snakes and occasionally larger newts such as the great crested newt.   

 

This smooth newt was found and pictured in the wooded area near the sainsburys centre on campus 

Life-Cycle  

A smooth newts life cycle begins when the eggs are laid upon vegetation under the water, unlike frogs that lay their eggs in large spawns to allow for a few to survive smooth newts instead distribute their eggs in little clutches, wrapping each one in the leaves of various aquatic plants in order to conceal them from predators, the female will also pick multiple different locations for eggs so if one is happened upon by a predator it will not consume her entire clutch in one go. 

After only 10-20 days the larvae will emerge from their eggs and spend roughly 3 months developing in the body of water before they undergo metamorphosis into efts, now better adapted for terrestrial life with developed limbs these efts will leave their body of water and make for wooded areas. It is not uncommon then for these juvenile newts to not return to a body of water until they reach sexual maturity which generally happens between the age of 2 and 4 years old. Once this age is reached they return to a body of water to undergo the same intricate courtship display that their predecessors performed. Some newts will even return to the pond where they were born to breed. It is also not uncommon for some efts to overwinter in ponds for an extra year instead of immediately heading into the forest. The average smooth newt has a lifespan of 6 years due to predation and disease however they have been known to live up to 14 years old if fortunate enough, however this means the average individual will only have 2-3 breeding seasons in their life hence why competition is so fierce.