"Slug"ging Along...

In recent weeks we have been experiencing a strange phenomenon in our back patio.  Slugs.  Lots of them.  I'd say at least a hundred a night when they are there.  They are only there at night and by morning they are gone.  And while you would think a slug would be a slow mover, apparently they are not since as recently as last night we had a few that made it thru the open slider door (screens are not common in Barcelona since we "supposedly" don't have mosquitos to worry about) and about halfway across our living room floor before we noticed them!  This was the night after one had managed to climb up to the door handle and when I went to close the door at night accidentally had it in my hand - you may have heard the scream back there in the States!

It appears they show up more often after it rains - similar to the earthworms we get at home in the driveway and streets after a good rainstorm.  The only difference here is that we don't know where they come from! 

We know the earthworms are aptly named because they come from the earth.  The grass and soil absorb so much water in a decent rain storm that they are forced to come up for air above the surface.  But here in Barcelona, in our apartment in particular, we have no grass.  We have some fake turf that we put on top of some wooden planks but not that these slugs are bright by any means but I'm going to guess they know the difference between turf and actual grass and soil.

So we have a few questions about these slugs:

Where are they coming from?  According to the website I just checked out - it appears that most slugs are your garden variety.  I don't have a garden, I don't have grass, so I'm not sure why they are attracted to our patio.  The 2 likely places they are coming from is our drain and from under the wooden planks we put down over the rocks so the kids would have more play area (you cannot pay me to look under there - perhaps we will send Josh out later!).  Apparently they thrive in high moisture.  I find that very interesting that they would even be here in Barcelona - we get maybe 40-60 days of rain per year and the air is more dry than humid - so how did they end up here? 

Where do they go when they aren't infesting our patio?  Are they coming from the drain that is in the middle of our patio and being forced up when it rains not unlike the earthworm from his home?  They are noctural (fun fact for you Aidan) and come out to feed at night.  But they go to their "home" to sleep all that food off when they aren't here I guess.

And finally what good are slugs?  We know that the earthworms help to cultivate the soil and are good for grass and crops.  Slugs are absolutely no good, destroying crops by eating roots, leaves, stems and fruits - and I should have no problems with my conscience if I get rid of them.  They do not eat bugs or help the environment according to what I have just read.  All I need are some toads, snakes, ducks, chickens and raccoons which some of the most common predators of slugs.  Those should be pretty easy to find here ;)  Until then I guess we'll just have to deal with our little nocturnal guests and keep our doors closed at night!

Just a few fun facts I found out:
*  Slugs are hermaphrodites, having both female and male reproductive organs.   Apophallation allows the slugs to separate themselves by one or both of the slugs chewing off the other's penis. Once its penis has been removed, the slug is still able to mate using only the female parts of its reproductive system.  (Men reading this be thankful we don't do that to you after mating!).
*  They actually have two pairs of antenae on their head - the top is for sensing light and the bottom for sensing smell.

They seem to gravitate to the food and water bowls which now need to be rinsed daily!  Disgusting!!!!

Julie