Newt survey season runs from mid-March to mid-June, with the peak season being mid-April to mid-May. I’m doing quite a bit of ‘newting’ this year, and it occurred to me that I’ve never done a blog post about separating great crested newts and smooth newts.
The first major difference is size. GCNs, when fully grown, are whoppers compared to smooth newts. Take a look at the photos below of a smooth newt male vs a GCN female, both in the bottom of 2-litre bottle traps…
Great Crested Newts are black in colour, with tiny white bumps (which give them their other common but erroneous name – ‘Warty Newt’). They feel slightly rough to the touch. (So I’m not joking when I say “I can identify a Great Crested Newt with my eyes closed!”)
They also have bright orange bellies (with no white or cream), with elongated black splotches in. The orange colour extends along the underside of the tail, and the tips of their toes are bright orange:
Males (and only the males) also have a silver flash on the tail, and (when in breeding condition) a large, elaborate, jagged crest down their back, which gives them a bit of a Godzilla vibe. The GCN really has TWO crests – one for the back and one for the tail, as there is a noticeable break in the crest where the tail joins the body.
But don’t let the name fool you, because Smooth Newts also have crests! Read on…
Smooth newts are, well, smooth. They are extremely variable in colour, and like the GCN are sexually dimorphic (males and females look different). Males can be brown or almost black, with big round black spots on an orange and cream-coloured belly, whereas females are usually a variable shade of brown or orange. Females also have a pale orange and cream belly, but the spots are fine speckles rather than big splotches. Female toes don’t look ‘painted’ like a GCN, and male hind toes are flattened and fringed. In a smooth newt, the crest is continuous and runs the entire length of the body, and is wavy rather than jagged, matching the wavy outline of their feet. Think of it as matching tie and shoes.
Below are a few comparison photos. Firstly, a photo of an adult female smooth newt with an adult female GCN (to illustrate the incredible size difference):
Here’s a comparison of the bellies of male GCN (L) and Smooth (R) newts:
And male smooth (L) vs GCN (R) toes!
To make things significantly confusing, for half of the year, this sexual dimorphism isn’t there – and fringed toes and silver tail flashes disappear for the winter, and the crest reduces to almost nothing – often seen as a faint line down the backs of males. Generally speaking, GCN males and females are harder to tell apart at that time of year, or before they reach sexual maturity. It’s a bit easier with the smooth newts as the belly patterning remains fairly distinct. But even the larvae of these two species can be separated.
By August there are larvae swimming about in GCN breeding ponds. Because GCN and smooth newts will readily cohabit in a pond, the larvae of both species are present. The difference is pretty astounding. Here’s a photo of the two species at roughly the same stage of development:
So as you can see, the GCN larvae are massive, compared to a similar age of smooth newt. The GCN also have distinct splotches on their body.
So now you know how to tell them apart. The sharp-eyed among you will notice that I have left out Palmate newt, largely because I don’t encounter them often here in the midlands, and as such don’t have any photos, but also because telling palmates from smooth newts is a little trickier, and I’m likely to have a proper rant about poor biological recording practices. 😉 A tale for another day, perhaps?
*Please remember that it is illegal to disturb, handle or even photograph a Great Crested Newt, as they are a European Protected Species and you need a licence from Natural England to disturb them. If you’d like to get involved in amphibian surveys and conservation, contact your local ARG (Amphibian and Reptile Group), or contact Froglife and ARCTrust.