RAUK - Archived Forum - Wall lizard distribution

Here's my first stab at confirmed/possible? locations of Pm colonies here in the UK. I would welcome comments, corrections, confirmations etc.

Ta.

Hi Steve

The location of Shoreham (shown as near Orpington) should be on the coast at Shoreham-on-Sea. Within the London suburbs, Charles Snells colony at Kidbrooke is possibly still in fragmented existence, and the Portland populations have spread over most of the cliffs, east and west. The is at least one other Dorset population at Winspit quarry, as noted in yesterdays post. My memory is rather vague now, but I also seem to remember there being a small colony on one of he railway viaducts in SW London, plus a couple of others in 'inland' Hampshire.

It may be worth looking at this article - Quayle A & Noble M (2000) The Wall Lizard in England British Wildlife Vol12 No 2 December

The Shoreham population is on the coast in Sussex - I think are still there - J Baker photographed their habitat - garden walls etc

London - Kidbrooke, Shropshire - Ludlow & South West Hampshire (New Forest) are all mentioned.

Regards

Jon

Cheers guys. I'd completely forgotten about Kidbrooke! Stab 2 below.

Fantastic - Perhaps we could try and visit these sites to get some counts - Wall Lizard Monitoring Project or something?

I am heading to Isle of Wight and Portland in the next few weeks so I can get a few counts - standard transects etc

Regards

Jon

Jon,

It would also be interesting to see how far each colony has spread. Plenty about Ventnor, but I had a good search for them at Shanklin (E) and at St. Catherine's Point (SW), with no sign at all. I wonder how long 'til some colonies link up?

I'm certainly interested in confirming absence/presence at some of the questionable sites, and I bet we've missed some populations.

Suz,

The only reference I have for Totnes is:

"In 1954, Lord Chaplin released 15 into the garden of his estate near Tornes, Devon; and by 1976, these had been known to have multiplied to around 100."

also:

"In 1937, 300 were released in the grounds of Paignton Zoo, and these were still in existance in the late 1960s."

I can't find a Tornes in Devon, but I have traced a Viscount Chaplin who was "a leading member of the horticultural society" (so not beyond character to add some lizards to set off his nice new plants). I know he planted gardens between Dartmouth and Totnes (Blackawton area), So I'm currently assuming Tornes = Totnes. I have one reference to Tornes being the last bridge on the river Dart, which kinda fits too.

I'd be grateful if people who know the area better can cast some further light.

Steve,

Thanks for the info I'll get on the case and do a bit of research before setting forth.

Is there any further steps which could be taken to tip the balance in favour of the sand lizards? how good is the habitat for the sand lizards or do they occupy the same type of habitat on the cliffs?

Jon

What evidence is there that it is the Wall lizards that have caused the decline in Sand Lizards? apart from one species is getting less (Sand) while the other is increasing (Wall) - As you say David the taks of removing the aliens would be futile when all that may be needed is some type of specific management for sand lizards.

Jon

Question:

Are Wall lizards territorial ?

I regularly see Lvs (in small numbers) in close proximity to Pm, but then Lv wouldn't need access to (possibly defended?) egg-laying sites.

Pm appear far more agile, I have seen an Lv and a Pm chasing the same spider, and the Pm won hands-down, was faster and turned far more quickly even though the Lv had a small head-start. But their coincident distribution would suggest this is not a significant factor for species exclusion?

Hi Steve

Its the La which people would be worried about like David says it appears that the decrease in sand lizards on Boscombe cliffs may be the result of the increase in Wall Lizard numbers. But like a lot of wildlife issues relating to introduced animals - e.g. Marsh Frog and apparent ill effects on Common Frogs - this has still to be proven discounting all the other reasons why sand lizards are declining and that wall lizards are increasing - the two may be unrelated (possibly)

Regards

Jon

Aye Jon, I was being too subtle I think (unusual for me :P). I should phrase my thoughts more explicitly!

I was exploring possible mechanisms, as I regularly see Lv and Pm co-habiting, but have not seen La and Pm together (personally), it led me to a potential hypothesis that competition for egg-laying sites might be a factor, as Lv obviously doesn't compete in this manner.

Thoughts ?

I have on occasion seen Pm and La together on the Bournemouth cliffs but have seen no interaction to give a clue as to the possibility that the apparent reduction in La numbers is due to the Pm. I am not sure that egg-laying sites would be the answer as Pm is far mroe catholic in its choice of egg-laying sites - it likes sand but will happily use other features - under stones for example. Many years ago I had both species sharing a large outdoor vivaria and they co-existed perfectly well even though both can be very agressive. 

Three factors are clear - Pm is far more adaptable to habitat change/sub optimal habitat, it is faster more efficient predator and it will produce multiple egg clutches (three or four) against La's one or two with quicker incubation - thus higher chance of alter clutches hatching.

Most recent version of the distribution.

If anybody could confirm that any of the 'questionable' colonies still exist, and email or private message me with sighting co-ordinates, I'll update the plot.

Cheers !