I am currently reviewing Amphibians and Reptiles by Trevor Beebee and Richard Griffiths (the things I have to do for this forum )
On page 62 there is brief reference to (RG) finding Palmate Newts in water filled tractor ruts in the west of England.
I observed this also in 1986, a rough pasture in Surrey had between 7-10 deep ruts filled with water (the area was reasonably boggy at this time but has now become much drier due to the formation of an adjacent pond, the ruts appeared to have been formed at least a year before judging by vegetation growth around the edges)
The ruts were literally packed with many hundreds of Palmate Newts, one on top of another, very actively moving in bright sunshine. I spent a few hours watching the local Grass Snake population taking full advantage of the situation. (I also observed many Adders in the general area but none were seen to feed on the Newts)
I have often wondered why, when an established garden pond lay approximately 50m to the West, and a purpose built new amphibian pond lay approx. 25m to the East that the Palmate Newts chose to congregate in the ruts. The only advantage I could see was a very high temperature in the ruts, placing a hand in amongst the newts, it felt quite unnaturally warm.
Has anyone else observed this in Palmate Newts or other Amphibian species?
A similar strange aggregation was uncovered when Mervyn and I were moving spawn at Dartford. A local volunteer removed an old newspaper from the pond, only to find it contained in its folds around 28 adult Smooth Newts. Again the paper and water in the area felt unnaturally warm to the touch. No other Smooth Newts were observed elsewhere in the pond.
I am interested as both these observation suggest to me a plausible survey technique for newts, anyone have any thoughts, similar observations or heard of heated traps for newts ever being described or used?
As an addition to the above, is it possible that bottle traps act in this way?
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