I have assumed this is in the UK? There are only 3 newt species; this looks like a Smooth newt (Triturus vulgaris), but I don't know if it's a female or a male outside breeding season. It can be distinguished by its throat spots which are absent in both male and female Palmate and Great crested newts. In the breeding season the male Smooth newt develops a continuous crest along its body and tail.
I have been following this thread for a long time without daring to say what I think, because I felt I would make a fool of myself. But here I go, because it haunts me: I think it could be a hybrid between the Smooth Newt (Triturus vulgaris), from which it has the spots on its belly, and the Alpine Newt (Mesotriton alpestris, or Ichthyosaura alpestris, or whatever it’s called today). This would explain its overall appearance an the lack of crest in its aquatic phase.
It may seem like a long shot, but where I am from (Eastern Romania), there is a place where a hybrid population used to thrive in a small lake and around it, so I know it’s not impossible.
That's really interesting I hadn't realised we had some populations of a non-native newt that had been introduced into the UK. Do you know where it came from? apart from hybridising does it pose a threat to the UK species?
I found this on a British site:
They say the Alpine Newt has been introduced intentionaly, but it's not a threat to the native species.
Thanks for the interest.
Here's the information about the newts habitat.
There are at least 100 newts in a large pond in a school playground in Stoke Newington, North London.
The pond has been there for about 20 years and was opened by David Bellamy.
It is surrounded by high brick walls and busy roads, and I can't think of any other pond nearby which they could safely migrate to, so I think it's population is definetly isolated.
Unfortunately the school is getting rid of the pond, so I've been trying to find suitable locations to take them to.
I have already taken 40 to two new ponds that have no other amphibians or fish in them.
Your suggestions have made me think I should be extremely careful about where I put the others I've yet to rescue.
Your information has been really useful and helpful even if we're still not sure exactly which type they are.
a population isolated from both other newts and from most predators as its in a town could certainly produce these differences to the native newts as there's virtually no natural selection occurring, this is really interesting i found similar when i introduced woodlice to a vivarium i kept frogs in for after just 2 years i had the normal black woodlice, but mottled black and white ones, mottled black and terracotta ones, completely terracotta ones which are clearly very different to the wild population