Saturday, 12 November 2016

Meet the Molluscs

On a beautiful November morning, we went with Dr Adrian Sumner, expert in slugs and snails, to explore along the Water of Leith centre and Redhall walled garden. Despite being a bit late in the season, and many of the invertebrates having retreated to hide from the cold weather, we saw seven different species of snail and nine different species of slug, and discovered the variety and beauty of these underappreciated animals. 

Trails on a wooden fence where slugs have scraped off the algae
The Smooth glass snail
The Cellar snail is shinier
The beautiful Lymicus maculatus is brindled all over. Like many molluscs, it first arrived in Britain about 40 years ago, and it seems to have pushed out its native relative.
By far the largest snail we saw, the Garden snail, which likes to live in colonies. There were at least three hiding in this crack in a wall under some ivy
The fungi was good too!
The elegantly striped Valencian slug is another incomer which is now widespread. They come in for example in plant pots and wooden pallets, and many appear benign although some are destructive either to native relations or to plants.

Arion distinctus is a slug with a bright orange sole of its foot, and a black back: here in an undignified upside-down posture.
The Grey field slug: not very fancy-looking, but a native. It's also the bane of farmers as it does love a nice monocultural crop field. 
Just for a change, it's a Shield bug!

The beautiful brown striped Copse snail
Another bigger copse snail, looking like a conker - or perhaps a toffee apple.

The Girdle snail was common around Redhall garden. It has a distinctive sharp 'keel' running round its shell. It came over from France and stayed in the south of Britain for a long time. It has only recently been recorded in Edinburgh but is becoming well established around Scotland. 
The Strawberry snail has a 'shoulder' rather than a sharp keel, and a big umbilicus (hole underneath)
There are many species of these little round snails, and once you've found one, you'll find lots!
The Tramp slug is a rather aggressive invasive
Slugs can have keels too! This one is called Tandonia sowerbii. I think it looks like it has a mohican...
Another beautiful slug, Limax maximus, has a brindled mantle and striped body. Its much rarer relative, Limax senerio niger, is an important ancient woodland indicator
Another upside-down slug, and another incomer, the Budapest slug, has a distinctive pale sole with a dark stripe down it.
These Budapest slugs were mating. Aww! 
A Brown-lipped snail, colourful, variable, beloved by Thrushes, and with a distinctive brown edge to the opening of its shell. 
A final slug: Arion flagellus, with brown stripes down its sides.

Many thanks to Adrian for lending us his expertise for the afternoon! If you are interested in finding out more about molluscs, have a look at the Conchological Society of Britain and Ireland, There are only about half a dozen mollusc recorders in Scotland, so they are badly under-researched, so if you are interested in contributing to knowledge of Scottish ecology you could make an important contribution.

Wild Reekie is a group which runs ecology and conservation events around Edinburgh. If you are interested in future events, please follow our Meetup group. You can also follow me on Twitter @eleanormharris.