Tuesday, 14 January 2020

The Curious Case of Climbing Newts

My eye was drawn to a post in the UK Amphibian and Reptile Groups Discussion Forum on Facebook which reported that as many as 50 Palmate Newts (Lissotriton helveticus) were found in reeds and low vegetation as high a three feet—nearly a metre—from the ground. Various comments followed as to why they may have been doing that when their breeding pond was close by. One of the comments was from Henrik Bringsøe in Denmark pointing out that he had written a paper on similar behaviour he and others had observed in the Smooth or Common Newt these days known as Lissotriton vulgaris, rather than the Triturus vulgaris we grew up with.



Bringsøe reported newts being found on the trunks of trees, on leaves and branches in vegetation about 40-50 cm above the ground and on the top of dead rushes at the edge of a pond. One was found 180 cm above the ground on the branch of an alder. Another, which was possibly attracted to invertebrates around a lamp, was found at a height of 2 metres on the wall of a house.


From Bringsøe, 2013


An obvious question is why this phenomenon has been so rarely observed. I could find no mention in either of the old standard books on British amphibians and reptiles, Smith and Frazer. Has it simply been missed or not reported?

There are all sorts of possible explanations for this little-reported climbing behaviour by amphibians which seem so ill-equipped for any sort of arboreal life. Indeed, there may be more than one reason with seeking food on vertical surfaces an obvious example. One suggestion that has not previously been raised might pertain to the climbing into vegetation near breeding ponds. Newts—both males and females—are known to use pheromones in courtship in their breeding ponds. Could it be that they are using an elevated position to ensure pheromones are further and more widely distributed in the surrounding air currents rather than relying on short-range diffusion close to the ground? Importuning—I’m here, come and get me’—could be what some of the climbing newts are up to, the unpaired ones climbing into reeds and shrubs to advertise their presence. 

Bringsøe H. 2013. Height-seeking habits of the Smooth Newt, Lissotriton vulgaris – a neglected behavioural trait. Mertensiella 19, 131-138.

Dusenbery DB. 1992. Sensory Ecology. New York: WH Freeman.

Frazer. D. 1983. Reptiles and Amphibians in Britain. London:Bloomsbury.

Smith M. 1954. The British Amphibians and Reptiles. Revised Edition. London: Collins

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