30 March 2009

Evolving snails: launch of Evolution Megalab

Continuing today's snail theme, today is the official launch of the Evolution Megalab, a project being run by the Open University where people can contribute to evolution research by surveying the Brown-lipped Banded Snail Cepaea nemoralis. There's been quite a lot of publicity about it today, and it is part of the OU's celebration of Darwin 200.

Anyone can take part in the survey, and the Megalab site has full instructions, along with associated videos (see below) and an identification quiz you can take to rate yourself as a Cepaea identifier. Cepaea snails have a long history as evolutionary study subjects, and the Megalab gives you the chance to add to this body of work. You can also see what historical records are held for your area.

For those with mixed feelings about snails, there is no need to hate Cepaea snails! They prefer dead or decaying vegetation and although they can be common in gardens they don't do much if any damage.

Snail identification: new edition of FSC key

Robert Cameron's excellent Key for the identification of Land Snails in the British Isles was published by the Field Studies Council in 2003, and a new edition came out towards the end of 2008. I was unable to resist getting the new one, despite being an infrequent recorder of snails who was quite happy with the old one! Was it worth it?

The new edition is not very different (e.g. 84 pages as opposed to the original's 82, and this has only changed due to the inclusion of a few new references), but it does contain four additional species, some corrections and some updates to the nomenclature (scientific names), quite a few of which have changed. The four new species are:
  • Myosotella denticulata. This is very similar to M. myosotis, and they are both species of tidal standlines and edges of saltmarshes. Both key out at the same place, and Cameron doesn't attempt to distinguish the two fully. Further information on separating these species is available in Roy Anderson's 2008 checklist of UK non-marine Mollusca, which can be downloaded from the Conchological Society.
  • Balea heydeni. This has been split from the similar B. perversa, and it seems that the 'new' species B. heydeni is actually the commoner of the two in Britain and Ireland, so previous records of B. perversa will have to be classed as an aggregate of the two species unless they can be checked. Balea spp. can be found on trees and rocks (the first edition of the key rather intriguingly says that B. perversa [agg.] is often found in places with few other snails, but this descriptive text has been sacrificed for lack of space in the second edition).
  • Papillifera bidens. A Mediterranean species that has been introduced into Britain; the only confirmed records so far are from a National Trust property in Buckinghamshire. Superficially similar to other clausiliid snails but with a distinctive dark band and white spots running round the shell.
  • Cernuella aginnica. Another introduced species that has so far been found only in Kent, and is not thought to be widespread. It is very similar to the common C. virgata, and requires dissection to confirm (features described but not illustrated in the key).
The only one of these that people living away from the coast are likely to encounter is Balea heydeni, so if you already have the first edition you should be quite safe to continue using it. But if you're keen to watch out for the latest introductions then the second edition is essential.

And if you don't have the key at all I would recommend it to anyone with an interest in snails - it is a thorough and careful key, but very well laid out and easy for a beginner to get to grips with. I particularly like Robert Cameron's introduction to using the key, which starts:
"Experience has shown that there are two extremes in reactions to keys. One is the expectation that a good key should lead simply to the right answer, even in the hands of a beginner. The other, sometimes expressed by experts, is that keys never work well, and that only face-to-face tuition by an expert works properly. The first view leads to frustration, or even despar. The second can have the effect of making identification an arcance professional preserve."
Robert goes on to chart a middle course between these extremes, providing guidance on how to get the best out of using a key, and what limitations have to be borne in mind. He demonstrates this advice well in his own key.

5 March 2009

OPAL soil and earthworm survey

The work I'm currently doing at the Open University's Biodiversity Observatory is part of a much bigger project called Open Air Laboratories (OPAL). The aim is to encourage more people to find out about their environment, get involved with the science associated with environmental issues, and learn more about wildlife and conservation.

One of the (many!) activities that OPAL is promoting is a series of public participation surveys, and the first of these is now up and running. It is devoted to soils and earthworms. The survey asks you to select a suitable site, do some simple tests to assess the nature of the soil, and find and identify a range of common earthworm species. You'll need to do a small amount of digging! The results are posted online and can then be seen on the survey map (some are appearing already).

In terms of biological recording, earthworms have been rather neglected in this country, perhaps surprisingly given our penchant for recording other rather obscure invertebrate groups, and at the moment there is no recording scheme nor published atlas for earthworms. The OPAL survey provides a well-illustrated Field Studies Council key to 12 common species of earthworm (download from the OPAL links given above), but if you want to take things further and look at the full range of species the Natural History Museum is seeking volunteers to undertake full surveys of worms in natural habitats. Training in the use of the full key by Sims and Gerard (1999, Synopses of the British Fauna, [currently out of print] UPDATE: now back in print) will be given. For further details of this, contact:
Dr David Jones, Soil Biodiversity Research Group, Department of Entomology, Natural History Museum, London, SW7 5BD. 020 7942 5706 or dtj [AT] nhm.ac.uk

While we're on the subject, there's a lot of good information on earthworms at the UCLAN Earthworm Research Group, and some fun video footage of Lumbricus terrestris at ARKive.