Tuesday 30 June 2015

What lies beneath

In early June, at the South Terminal long-stay car park, a small group of ecologists gathered for Gatwick's final newt survey of the season. 

Not the most obvious of wildlife settings, but a secret short cut from here takes us through to some secluded woodland ponds. These ponds seem to have been here a long time and are home to five different species of amphibian, all native to the UK. 

The infamous Bill Wadsworth of Chris Blanford Associates

Great Crested Newts are fully protected under UK and European law and you must be a licence holder to survey for them. Bill is a newt-extraordinaire, monitoring this pond over a number of years since the completion of a new water treatment area nearby. Counting newts means that we can estimate the population density, keeping an eye on the population health and ensuring that no long term impacts are apparent.

Specialist torches are used (1 million candle power) in order to cut through murky waters. The first thing we came across on this evening was....

Mirror Carp (Cyprinus carpio); a massive one at that

Not quite what we were hoping for! Fish are voracious predators of newts and so do not often occur together, however this particular pond is one we are restoring for amphibians. The fish were artificially introduced here, so this coming autumn electrofishers will humanely remove and relocate them, relinquishing the pond back to our amphibian friends. 
  Over to the next pond; now this is more like it....

Great Crested Newt (Triturus cristatus), male

Either a Smooth or Palmate Newt (Lissotriton sp.), female

Torching is quite a challenge in these particularly murky waters, resulting in a number of double-takes at a leaf-like-newt. Or is it a newt-like-leaf?

Common Toad (Bufo bufo)

Common Frogs and Common Toads are also quite a challenge to spot, until you get your eye in, then they are blooming everywhere!
   Another method to survey for newts is bottle-trapping, which might sound ridiculous but is very effective...

Preparing bottle traps

When Fat Duckweed dominates the pond surface, torching is out and bottle trapping is in

Trapping newts is quite an intrusive way to count them, so we only do it here when absolutely necessary, again with appropriate licences. The traps are placed out the day before and then collected back in very early the next morning; we want to minimise any disturbance to these guys and gals.

Great Crested Newt (Triturus cristatus), female
 This one is quite odd in lacking belly pattern

Great Crested Newt (Triturus cristatus), female

Ecology student Mark gives us a hand with the traps

Newts love hitting the bottle

Smooth Newt (Lissotriton vulgaris), male

Palmate Newt (Lissotriton helveticus), male, 
with heavily webbed back feet and a filamentous end to the tail

Palmate Newt (Lissotriton helveticus), female. 
The throat of this species tend to be rosy pink and unspotted

The breeding season is over for another year and most newts are leaving the ponds, but the next generation are still there, lurking just beneath the surface...

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