Tuesday, 7 May 2013

Great but crest-less

I've been bothering wildlife in ponds for most of my childhood but I've never come across one of these before... actually, I only saw my first Great Crested Newt early last year when another Ecologist was surveying for them at Gatwick. Last Tuesday we carried out our first G.C.N. survey of the year, the result of which was seven thumping great big females like this one.

A female Great Crested Newt (Triturus cristatus), about 14cm in length

It is slightly odd that the individuals we caught were all female as the males are generally the first to arrive at breeding ponds. Only the males have the impressive crest which runs along their backs, which I am yet to see! It may be that the relatively cold spring has confused breeding cycles somewhat, so it will be interesting to see what turns up in the next few weeks.

 Emptying the bottle traps with James Webster of EHM and ecology volunteers Katie and Kwame

The overall population trend shows these impressive fire-bellied amphibians have suffered a decline in numbers in the UK, probably due to agricultural intensification and loss of suitable habitat. That’s not to say they're not around: in fact, people have reported G.C.N. turning up in some rather interesting places including water-treatment ponds and concrete pools! However for breeding sites they tend to favour medium-sized bodies of deep water with good vegetation cover.

By taking photographs of the undersides of GCN we can identify individuals and estimate the population

 Underbelly of the beast: the plastic box and sponge doesn’t hurt them, think of it as like a damp foam-hug...

We gently hold them in place while photographing the exotically-patterned underside, creating a database of individuals. These ladies were all rather cold and sluggish so cooperated well to being handled before we released them back into the pond. We also caught some of our other two native newt species...

A female Smooth Newt (Lissotriton vulgaris) which has distinguishable spotted throat, and is around 9cm in length

A male Palmate Newt (Lissotriton helveticus), which has the indicative tail filament and webbed back feet

Female Palmate Newts, distinguishable from the female Smooth Newt by their pale pink, unspotted throats. The aquatic plant also occurring in pictures is Fat Duckweed (Lemna gibba)

We are continuing our surveys for G.C.N. over the next few weeks at the Land East of the Railway Line. All amphibians are protected by UK law and Great Crested Newts receive full protection, which means it is not permitted to capture or disturb them without a licence. You can read more about these and other UK amphibians at www.froglife.org