Grovelling for snails

I’m standing on top of a windswept hill somewhere in England, and there’s a man in an Australian ‘buckaroo’ hat trying to explain something about this area of grassland and escarpments, but the wind whipping around is so loud that each time he talks I just see his mouth open and close, and I can’t really hear anything he’s saying.

Class Field Trip No. 2. We’ve actually come all the way to Buckinghamshire this time, to a place of chalk and limestone called the Chiltern Hills. Pulpit Hill Nature Reserve is one of the largest and most important of these sites. It comprises what’s called ‘calcerous grassland’, large tracts of open grass underlaid by lime-rich, nutrient-poor soils. Traditionally, these were kept continuously close-cropped through grazing by sheep and rabbits. Now that the old ways of farming have been discarded and forgotten, the grasslands are slowly falling away under the determined onslaught of scrub and woodlands.

We’ve come here to grovel for snails. I can say that with confidence, because that’s what’s actually stated on the assignment sheet we were given: “Make sure you wear gloves when grovelling in the deep undergrowth”. I found that quite amusing when I first read it, although no one else seemed to get it. It’s not everyday you can tell people that you went grovelling.

The specific reason we’re here is a certain species of snail called Cypaea nemoralis. I’m not even sure whether it has an English name. This little invertebrate has generated much excitement and fascination within the realm of evolutionary studies because it’s such a perfect, easy-to-observe case study of selection in action. Selection in Action! That actually sounds quite sensational. There’s an incredible amount of variation within this one species. For a start, it comes in three main colours: brown, yellow, and pink. That’s right – chocolate, vanilla and strawberry flavours. Then there’s the different number of bandings, from five stripes all the way down to none. Who could resist such pretty little trinkets?



We slap on the rubber gloves and start grovelling in the undergrowth. We’re blessed with kind weather today – although the wind is whipping all around us, the sun is smiling down, and it’s an unusually pleasant day. We’re supposed to be three to a group, but I’m one extra person, and I decide to impose myself upon Sanjay, Shashwat and Sami. We mark out a plot of 10 square metres and before you know it we’re entirely focused on snails, snails, and more snails. And there are lots of ‘em here. All you can hear are cries of “Adult, live, yellow, five bands!” and “Subadult, dead, pink, no bands!” and variations upon this theme. Sanjay, Shashwat and I are grovelling, and Sami, looking like a shady character in a B-grade gangster movie, is frantically running around trying to jot all the data down. It’s engrossing work. You’d never think you could get so fixated on snails.



It's actually quite nice here, on your haunches, rooting around in the undergrowth. It's a place of cool quiet dankness, mossy and moist. As long as you're careful to keep away from the clutching brambles you're alright. And we’re all happy to be out in the field again, doing some real work. We chat, we laugh, we sing Bollywood songs. We even manage to squeeze a bit of birding in – kestrels, and even some red kites. Time in the field passes by like nothing at all, and before we know it, the shadows are getting long, and it’s time to wrap up and head back.


Who would’ve thought that counting snails would be a pleasant way to spend the day?