why are spiders important to our environment?

[the S.O.P]

Hi there i would like some ideas as to why spiders are important to our environment. I'm doing a scientific report for uni and am battling to find proper info in books or on the net. examples such as biological control etc. any input will be appreciated.

[Ales]

I don't think they serve a big purpose as like bees or flies,but they control bug populations and serve as food for other animals.
I'm sure there are other reasons they important.

[Puff the Magic Adder]

I'd say that their control of insect populations is fairly significant, and this is something that is very beneficial to humans when it comes to playing their part in controlling pest insects (e.g. flies).

An example from my own experience:
I have many spiders living with me in the flatlet where I stay - mostly Steatoda (Cobweb spiders) and Theridion (Comb-footed spiders), some Selenops (Wall spiders) and Salticids (Jumping spiders), a few Daddy Long Legs (though they seem to have become increasingly scarce around my house lately - no idea why), and occasionally Palystes (Rain spiders) and Cheiracanthium (Sac spiders). I don't keep them as "pets" or anything like that, they come and go by themselves (although I have "introduced" a few from other parts of the house when I've felt that they were in danger). I generally leave them to their own devices and do not interfere with them - coexistence with spiders really is no problem at all. One of the results is that the mosquito population inside my flatlet is considerably lower than in the rooms of the main house where there are fewer to no spiders at all. I've seen a number of mosquito corpses in their webs and have seen a Selenops pounce on a mosquito and eat it on more than one occasion. Residents in the main house have to use chemical control for mosquitoes (Doom, repellents, mosquito pads, etc), and this has actually proven to be less effective than my "biological control"; and with my "biological control" there are no chemical fumes to be inhaled, so it's healthier too.
Sac spiders can give a nasty bite which can leave a necrotic wound, but I have not yet been bitten by one. I have not seen that many around Cape Town suburbia though, but in the flat I had when I was in Russia there were quite a few Yellow Sac Spiders (Cheiracanthium punctorium) around in summer, but they never caused any problems whatsoever.
Mosquitoes in Russia during summer though are a much different story to the relatively pathetic little things we get in Cape Town. Russian mosquitoes, I'm afraid, do require some form chemical repellent as they are far too numerous (and large and aggressive) for a few little Sac spiders to take care of.

[Venom]

Maybe try to contact Prof.Ansie Dippenaar-Schoeman she will definatly be the right person for info.
E-mail: dippenaara@arc.agric.za
Telephone: +27-12-3569824

[Westley Price]

Topic is more than two years old.

I'm pretty sure the report is done.