 Hello again. Today's question, it's a very interesting one, might apply to you and that is what is the point of slugs? So this is very much about systems thinking and looking at the bigger picture and how do things connect together and we could also add different things on the end of that sentence so as well as slugs we might say what is the point of mosquitoes or midges or ticks or leeches or wherever it is that you might find a little bit annoying where you live for whatever reason okay something's nibblers or stingers and other things eat the things that we like to eat like rats and mice for instance they like to eat a lot of grains that's basically their natural diet and so they compete with us for those foods. So what we have to do is to look at the bigger picture and say why do we have so many slugs in the first place and Bill mollison famously said you don't have a slug problem you have a duct deficiency and it's quite funny to hear that phrase but at the same time it does make a serious point which is that for systems to work they need to be in balance and when we create imbalance by putting a lot of one thing for instance in the landscape then we attract a lot of the things that will want to consume that thing so we store lots of grains so we attract a lot of mice and rats and we give them lots of food so they breed you know they increase their numbers and the same is very much the same of organisms like slugs. Now slugs are really important in the soil okay let's let's give you the benefits of slugs slugs are really important in the soil they spend a lot of time underground in the soil itself rather than just on the surface and as they're doing that that sticky substance that they use off the outside of their bodies is helping to stick together the granules of the soil so they make larger tunnels within the soil just like lots of other organisms smaller organisms so fungi do it too worms do it as well at different scales and bacteria they produce a slime that allows them to stick to particles of soil so that they don't wash away because when you're that size of a blob of water coming down to the soil can easily take you off somewhere else and so all the things that live in the soil many of the things that live in the soil make substances that will help stick soil particles together to themselves to soil and so on and so forth and slugs are really important part of the drainage system of soil if you like so soil needs to be able to hold some water that's the organic matter in the soil is able to do that for the plants that obviously grow there and the life that lives in the soil but it also doesn't want to hold too much if you have a lot of clay for instance clay very tightly binds water and so what can happen is clay soils can get very wet and then there's not enough oxygen in the soil for the plants and the animals that live there so slugs have important benefits in the soil and many of them are about you know what they're called what are called detritivores and detritivores are things that eat the things that have died basically so many slugs are very important in consuming the dead material that is falls off trees and plants and you know dead animals and insects and so on that also are part of the system to recycle those things so small things tend to be pretend to find there's a lot of small things because when you're small you don't need so much food and so you can have many more of you in the landscape populations of slugs are much higher than perhaps elephants which of course need a lot more energy and a lot more food in order to maintain one elephant so there are less of them and generally populations of bigger things tend to go extinct more quickly because in times of food shortage their numbers drop to a critical level much more quickly for instance than small things like bacteria that've been around forever pretty much so what about those other things like mosquitoes and such well mosquitoes very what happens I would say if you have a mosquito buzzing around what do you do well if you're in a position where you might move you might just get out of there as quickly as possible part of the problem is that our ancestors would have been able to do that to run away whereas we want to stay in one place we basically create a home or a place that we stay and so we try and get rid of the mosquito but the role of the mosquito for instance in the system is that if you have for instance large animals and they're hanging around in one place for a long time they start to compact the ground and certain in certain places if you have clay for instance that compacted ground will start to puddle so when it rains or any water coming across the surface will start to puddle there that will attract mosquitoes like to lay their eggs in the water and the mosquitoes obviously will start to buzz around and the animals will if they can if there's no fences in the way in a natural ecosystem would go somewhere else so their role is to keep things moving in the same way that big predators do the same so if you're in a landscape and you're looking out and you're seeing large groups of herbivores for instance moving around they move around to look for food but also they're kept moving by carnivores that are chasing them trying to eat them of course so the big things and the small things that are trying to eat us do the same job they keep us moving and part of our problem is that we don't like to move anymore so whenever you have a question like what's the point of what are they doing here what can I do about them what you need to do is step back and say what is their role in the system what do they eat but what would eat them and that of course comes back to Bill's original answer about you don't have enough ducks so what would eat this thing to create a balance and an example where we live here is that we have pear trees out in the bank on a little gorilla forest garden and there are a lot of pheasants that wander through the area and they eat the little fruits at the bottom of the pear tree so there's a problem a problem called pear mage this little insect that flies into the the immature fruit and lays its eggs and then the fruit falls off and it spends basically it overwinteres at the base of the tree turns back into a mage and then flies back and does the same the following year and the thing that breaks that cycle are birds that come around and eat those things and that might be for you that might be chickens we don't need to have chickens in our system for that reason because pheasants are already doing that job so look at the system as a whole say what is this thing doing in the bigger picture and what can I do in order to break that cycle to reduce their numbers