RAUK - Archived Forum - Posts by RhysOwenRoberts:

Dear all

I'm new to this forum but hope that someone will be able to help me out.

I have a number of sites under my management which are owned by BAA Heathrow Ltd.  Two of these sites are closed access, situated around balancing ponds and support good numbers of grass snakes (with good weather, sightings are almost guaranteed).

I have identified Natrix natrix as an indicator for certain aspects of my management of these sites.  Therefore I wish to carry out formal surveys.  Currently I conduct a standard transect along which I note reptile species seen and numbers.  However I am keen to determine more strictly our population size through capture-mark-recapture and am seeking adivice on the best way to do this with minimal disturbance. 

I am aware of techniques for individual recognition such as belly patterns and scale clipping but in reality have no experience or idea of how easy this will be.  I do have experience of handling snakes (allbeit those from tropical Malaysia) but have not caught nor attempeted to catch UK snakes.  How regularly should surveying occur and what sort of impact would handling have on the population?  The site is not massive and fairly isolated (although there is a border with a river corridor).

Well, I hope that this is enough info, I look forward to any adivce or tips that may be thrown my way!

Thanks

Thanks for the tips!

Rhys

Robert

I got the email fine, thanks very much for the help.

Rhys

Robert,

Ok - ID02 and ID23; ID03 and ID24; ID31 and ID12.

I think!

I see what you mean though, once you look a little closer the markings are quite different.

 Tony

I know that grass snakes are also found at Harmondsworth Moor (BA Waterside Offices - just off the A4 near to the M25) so they are certainly fairly common in the wider area as a whole.  However, much of the land around Heathrow airport is fragmented sufficiently enough to present significant dispersal barriers.

The sewage farm sounds interesting(!) was it an actual airport site or just in the Heathrow area?  Of course it is possible that these sites still exist just under different names.

Rhys

Tony

Perry oaks is now the building site which will be the new Terminal 5 and the replacement water works is actually a site of mine. I am required to conduct bird surveys here (principally due to the location of the site under the flight path) but the site would no longer be suitable for grass snake.  I have seen little ringed plover there however, which were a nice sight, even if only briefly.

Perry oaks was subjected to a major conservation project which entailed moving an entire wet grassland (which supported water avens) to a new location.  This site has survived the whole process remarkably well and no doubt would present excellent snake habitat given some initiatives to provide egg-laying and hibernation habitats.  The only drawback is that open water is generally considered a no-no as planes and birds dont tend to mix well.  This site is due to come under my care in the not so distant future.

Rhys