By Ruth Brooks
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Snails and I go back a long way. As a child I adored them. I marvelled at the way they slid along their shiny tracks; at the fact that they had been around for six million years â€" gentle souls who did not kill or eat each other.
It was only later when I had a garden of my own in Devon that my ardour began to cool, to be replaced by fury. With rage in my heart, I would wander round my flowerbeds at night listening to them destroying my delphiniums, or chomping their way through my runner beans.
Enough was enough. I declared war.
Ruth Brooks research into the curious habits of garden snails led to some surprising results
One spring evening in 2010, I scattered a few pellets of poison round my vegetables and waited to see what would happen.
The following morning, my garden was a veritable graveyard of contorted mollusc corpses. Some were twisted into horrible convolutions, as if their final moments had been spent in the throes of agony. Others were still gasping their last, green froth oozing from every aperture.
‘You’ll get used to it,’ said a friend. ‘I felt just as you did at first. But think of it this way â€" it’s them, or the plants.’
I stuck it out for three weeks. Then one day I found a shrivelled worm with its head bitten off. Horrified, I wondered which of the lovely birds in my garden had started to eat it, been put off by the vile taste â€" the worm having fed on one of the pellets â€" then possibly died from the poison it had now ingested.
That day I vowed no more snails would die on my watch. So began a battle of wills that would drive me almost to the brink of insanity.
I read that snails hate coffee grounds. And yet whole armies gathered for long sniffing sessions of the grounds I spread out. Then â€" possibly drugged up on caffeine â€" they made a dash for my sunflowers.
I bought grit and gravel â€" snail-proof, said friends. The little blighters skipped over the rough terrain as if over a silk sheet. I could almost hear the tinkle of snail laughter.
An organisation dedicated to organic gardening recommended I try bran as a barrier. The snails were supposed to gobble it voraciously, then swell up and die a well-fed death. Mine nibbled it as an hors d’oeuvre, and then moved on to my lupins.
Snails are not supposed to be able to swim. M ine did. Bobbing their way across a series of water-filled moats became some kind of snailish extreme sport.
Then, browsing through the Guinness Book of Records, I came across Archie, the champion snail ‘sprinter’, who was capable of covering ten feet in 22 minutes. How long, I wondered, would it take my snails to travel this distance? And if I took them far away from their haven, would I see them again?
So I collected up a handful and dumped them by my garden fence, around ten feet from my flowerbeds. To identify them, I daubed their shells with a blob of red nail polish. I hadn’t a clue what I was doing but for the first time in months I was enjoying being in the garden, without obsessing about my ruined flowers.
Two days later, at least half of them were back and demolishing a new delphinium. I gathered them up again and popped them over the fence. Wou ld they bother clambering over the fence, and sliding all the way back?
A week later, they were nearly all back. By now I was intrigued. About 40 yards behind my garden was a small plot of waste land.
To get home from here my snails would have to cross two fences, or crawl along the pavement until they came to my front hedge, then make their way through the front garden and round the side of the house to reach their feeding ground.
Mission: To find out whether snails, when removed from their feeding and resting sites, would find their way home again, and from what distance
With the red spotted snails in a bucket, I crept out at dead of night and tipped them carefully into the long grass on the waste land.
I never saw them again. Maybe they were exhausted from all their enforced journeys. Maybe they were busy eating my neighbours’ plants instead of mine. I’ll never know.
What I do know is that I was disappointed. I wanted them to come back. And I wanted to prove to myself something that I had begun to believe in â€" the homing instinct of snails.
The following winter BBC Radio 4’s Material World invited listeners to send in research ideas for the forthcoming Amateur Scientist of the Year competition.
I sent in a 100-word proposal outlining my mission: to find out whether snails, when removed from their feeding and resting sites, would find their way home again, and from wha t distance. It had never really occurred to me that out of all the entries, my proposal would make it to the final four shortlist.
But now, a few weeks later, here I was, with just five months to conduct a series of experiments. Acting as my new mentor was Dave, an ecologist from the University of Exeter, who spends his time studying animal populations and habitats.
My first job was to prove the snails actually had a homing ‘instinct’. Were they acting on a whim as they meandered around or did they have an innate ability to return home?
With Dave’s help, I devised an experiment. We established a base where the snails would, we hoped, return again and again. This was my patio, or ‘Home’. The bait â€" a huge basket of petunias â€" was placed there.
Then I had to find a ‘control’ group â€" snails collected fro m another location. This would be the ‘Away’ group to see if they returned to their home area too. All would have their shells marked, and everything about their journeys would be recorded. Other variables, such as the weather or terrain, would be noted.
I found 14 home snails on the patio and 26 away ones lurking in the sysyrinchium, an iris-like plant with sword-shaped leaves. One by one I marked my Home snails with a blob of maroon paint. The Away snails I marked yellow.
I then set them on their journey from a metal tray that I had positioned exactly halfway between the Home and Away bases, a distance of around ten metres.
The snails moved off at incredible speed. Some started hitching a ride on each other’s backs. A couple even started climbing up my leg. A few days later, however, I made a triumphant note in my diary:Findings: eight out of the 14 snails from the Home patch were recovered in the Home patch and nine out of the 26 snails from the Away patch recovered in the Away patch. There was no crossover at all.
Two days later, I repeated the experiment with similar results.
Dave was ecstatic, posting a report on Facebook and urging the public to join in with the experiment.
My third experiment, however, was a failure. This time I collected ten from the Home patch, and 15 Away snails from three separate areas of the garden â€" the rockery, vegetable patch and strawberry bed. Once again I placed them on the metal tray and set each one off to find its respective way home, this time from almost double the distance.
Not one returned ‘home’. Why? The snails had been collected on the hottest day of the year. They would have been slower, less moist and more vulnerable to birds. Had this been a factor? They’d had to cross a lawn, not paving slabs â€" perhaps this put them off? Was the distance too far? Was I getting on their nerves, constantly disturbing them?
By now, my reputation as the mad snail lady of Totnes was taking hold in the town. I roped in neighbours to help with the project and drafted in children from the local primary school.
It took a little unintended tragedy to convince me finally of the genuine homing instinct of snails. In that ill-fated third experiment I had removed some marked snails from their favoured strawberry patch and taken them to the front garden. I finally found one of them some weeks later clinging for dear life to the side of my house.
My courageous snail had battled its way, in intense heat, all the way from my front garden, trudged round the corner of the house and staggered a further ten metres before throwing in the towel and perishing not far from home.
If anyone needed extra proof of a homing instinct, this was surely it. There was no possible other motive for that little snail to use up its precious moisture trying to travel more than 20 metres in the burning July heat unless it had a purpose.
Full of remorse, I buried it, with full honours, in the strawberry patch.
Many more experiments later, it was time to present my results at the competition final in Birmingham. ‘From the evidence so far,’ I declared, ‘it seems clear that Helix Aspersa â€" the garden snail to you and me â€" does have a strong homing instinct, over distances up to 30 metres.
‘For frustrated gardeners, it seems that it would be safe to take and place their snails elsewhere at a distance of 100 to 200 metres.
‘Ther efore, there is no need to kill them. The implications of not using pesticides are: healthier micro-bacteria in the soil and less danger of poisoning to pets and birds. And the feel-good factor for humans!’
I’d started the project with a simple question, letting the research sweep me along from one day to the next. But now, incredibly, I was declared the winner.
It had been an amazing summer and ended with the confirmation that no snail death is worth it. The gastropod deserves to live and thrive as much as the plants. If you end up with a row of half-eaten cabbages, well, so be it.
And now, three days after winning, here I was, in the September sunshine, back at home with my snails, who were even now creeping out of their hiding place â€" a group of hungry youngsters heading for the lettuce seedlings I had planted a few days earlier.
In th e garden, nothing had changed â€" except me. I had made peace with my snails. We were friends again. My life had come full circle.
Adapted from A Slow Passion: Snails, My Garden and Me by Ruth Brooks, to be published by Bloomsbury on March 14. £12.99. To order a copy for £10.99 (incl p&p) call 0844 472 4157.
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