Reptiles — And More — In Keston

Keston top pond seen from the Westerham Road car park.  14 May 2011.

Yesterday, a group met in the Westerham Road car park near the south end of Keston Common to look for reptiles. The walk was led by Judy John of BCS, the Countryside Officer for this area.

Keston Common connects through some wet and dry meadows to the ancient Padmall Wood. Spread around the common and the meadows are small squares of corrugated iron, perfect shelters for snakes and lizards, and Judy aimed to take us around them to see what we could find there today.

Of the six reptiles native to Britain, we might see three today; grass snake, slow-worm, common lizard. There are also adders in the area, living on Hayes Common, but they have not been seen in Keston. Judy showed us some cast-off adders' skins. Grass snakes are present; they have been seen swimming in the top pond, shown in the first photo.

The head end of the cast skin of an adder, Vipera berus. 14 May 2011.

As usual, I was interested to see what plants and insects were around, and Judy was well able to identify almost all of those I asked about. It is wonderful to be walking around with someone who knows so much.

First we went up to the acid-soiled heath. Lizards and snakes can tell when someone is coming by the vibrations caused by footsteps, so we crept up to one of the plates and gathered round as Judy carefully lifted it with a crowbar.

This was needed, not because it was heavy, but just in case there was an adder nearby; unlikely, but best not to take an easily avoidable risk.

There was nothing beneath any of the plates on the heath but for some ants and sometimes some signs that something larger might have been there. Then one of the children saw a lizard under a bush! But it ran off before the rest of us could see it. So far, so elusive.

Cat's ear, Hypochaeris radicata, on Keston Common.

But there were other things to see on the heath. A startlingly coloured black and red cinnabar moth flew by. There were stretches of wavy hair-grass, with shiny flower heads rippling in the breeze. We saw the yellow-flowered cat's-ear, identified for me by Judy. Unlike a dandelion, which the flower resembles, this plant has branched flower heads with occasional scales.

Sheep's sorrel was widespread; it is an early coloniser of areas which have been scraped to restore the heathland to its former state, as I also saw recently on Hayes Common.

Judy showed us the droppings of a roe deer, distinguishable from round rabbit pellets by their irregular shape and pointed ends. They look like quite small pellets for such a relatively large creature.

We moved on past the sphagnum bog — where cotton grass was visible, common elsewhere but scarce in this area — to a group of meadows, some wet and some dry. These were full of interesting flowers. In the wet meadow we saw pink ragged robin, white milkmaids, and lots of field buttercups. We should look for bog asphodel to flower here in July.

Female slow-worm, Anguis fragilis, under a metal plate at the edge of a dry meadow in Keston. 14 May 2011.
Taken with a Canon EOS 450D and a Canon EF 28-135 f/3.5-5.6 IS USM lens.

It was in one of the dry meadows that we saw, at last, a slowworm under one of the plates. That was exciting! It didn't like being exposed and slowly made its way into the grass, apparently undisturbed by spiders and ants scurrying around and over it.

Common blue damselfly, Enallagma cyathigerum.  Male.
Dry meadow, Keston, 14 May 2011.

Despite its snake-like appearance, this is a lizard. You might read that you can tell it from a snake because it can't protrude its tongue - that's clearly wrong, and here you can see that the tongue is even partially forked. But a lizard it is.

Judy says that she sometimes finds several slowworms under that particular plate. So we didn't see as many reptiles as we might, but I saw more than I ever have while walking round this common in the past. OK, just one more, but one lizard is much better than none.

Also in this meadow we saw a damselfly clinging to a grass stem. Damselflies are like smaller, more delicate dragonflies and they are all quite beautiful, even this common species. I saw a couple of colourful beetles too, including a red-tipped flower beetle.

We saw field wood-rush and the bright blue eyes of germander speedwell. I was interested to see common or lesser stitchwort, after seeing so much of the larger greater stitchwort in the area. There were groups of bluebells still flowering, and some white star of Bethlehem flowers, which Judy told us don't really belong there.

On the way back, Judy pointed out a treetrunk with an orange stain. This was caused by an alga; algae are normally green but this species contains a carotenoid pigment. This alga, Trentepohlia, can combine with a fungus to form a lichen. The fact that it thrives without the fungus shows just which of the partners in a lichen is getting the better of the deal.

Here are some more images from this very interesting and instructive walk.

Ragged robin, Lychnis flos-cuculi, in a wet meadow in Keston. 14 May 2011.
Taken with a Canon EOS 450D and a Canon EF 28-135 f/3.5-5.6 IS USM lens.

Wavy hair-grass, Deschampsia flexuosa, on the acid heath on Keston Common.  14 May 2011.
Taken with a Canon EOS 450D and a Canon EF 28-135 f/3.5-5.6 IS USM lens.

Common or lesser stitchwort, Stellaria graminea, on a dry meadow in Keston.  14 May 2011.

Dropping of a roe deer, Capreolus capreolus. Keston Common acid heath, 14 May 2011.
Taken with a Canon EOS 450D and a Canon EF 28-135 f/3.5-5.6 IS USM lens.

Judy John addressing the group in a dry meadow in Keston.  14 May 2011.
Taken with a Canon EOS 450D and a Canon EF 28-135 f/3.5-5.6 IS USM lens.

Judy John cautiously lifting a metal plate on Keston Common. 14 May 2011.
Taken with a Canon EOS 450D and a Canon EF 28-135 f/3.5-5.6 IS USM lens.

Ash tree stained by an orange alga, Trentepohlia. Keston Common, 14 May 2011.
Taken with a Canon EOS 450D and a Canon EF 28-135 f/3.5-5.6 IS USM lens.