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Slug sex


by Richard Jones

It may sound like a bit of a joke, but slugs are the supreme sexual acrobats, and their mating gyrations are sensuous well beyond the limits of their apparently simple slimy bodies.


Copulating slugsThankfully, Buster the guinea-pig has a thick night-time cover of old carpet, otherwise he might have been shocked to discover the fornication going on outside his hutch one morning last week. When I peered out from the kitchen at 6.30am, two great grey slugs (Limax maximus) were still in the throes of intense mollusc copulation.

It may sound like a bit of a joke, but slugs are the supreme sexual acrobats, and their mating gyrations are sensuous well beyond the limits of their apparently simple slimy bodies. When two receptive slugs meet, they climb to the vantage point of tree bough or bush branch and start to writhe together. In this case they had chosen the projecting ridge of Buster's cage as their launch point. As they twist, they secrete a special thick mucus, much tougher and stickier than their usual soft slime and this forms a dangling rope down which they slide. Usually, after an abseil of about 45cm (18in) in mid air, they start to spin in a slow balletic pirouette. All the while they coil their bodies around each other.

Copulating slugsThese two, though, had nearly reached the ground after 45cm, so their suspended acrobatics had turned into a kind of low-level pole dance. It did not stop them. Each inflated a huge pale muscular penis, and these too, contorted to grip each other, forming first a tight knot, then expanding into a broad round flower shape. This is the point at which each exudes sperm into the other. Slugs are hermaphrodites, their bodies containing both male and female organs, and the sexual pipework also accepts the sperm from a partner, and pumps it down (or up) to the waiting ovaries.

The whole process can take an hour of wriggling movements, and when they have finished, they drop, with a plop, to the ground. Having already arrived at the ground these two simply disentangled and slouched away. When I later uncovered Buster, he was none the wiser, but I was very pleased to have come across something I had never seen before.



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Gardeners' World Web User 15/09/2010 at 11:07

Wild life mating can be very fascinating. i have two collar doves which kiss beaks for ages before mating on next door's roof! The time od day does not seem to bother them but we will all have to get up very early to watch the slugs it seems. After all that gymnastics how can people step on their offspring?

Gardeners' World Web User 22/09/2010 at 07:20

I saw in my garden late yesterday afternoon a lot of dragonflies whizzing back and forth and wondered why. Is this the time for something I haven't noticed before. I live on the Isle of Wight and the weather has been lovely for the last few days.

Gardeners' World Web User 25/09/2010 at 09:46

"when two receptive slugs meet" Now there's an interesting thought Richard. I wonder what the chat-up line is?

Gardeners' World Web User 25/09/2010 at 20:54

I have never seen slugs or snails mating but I used to keep the large garden snails as a child and found a chalk 'arrow' in their jar one morning.

Gardeners' World Web User 26/09/2010 at 11:33

Please could we have a repeat of Gardener's World say on a Sunday morning as we are not all able to watch on Friday evening. It would be greatly appreciated.

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