Alternatives to Deltamethryn, mosquito spray?

[Paramvir Singh]

My building in Mumbai sprays a lot of Deltamethryn to get rid of mosquitos. Although in the long run, it isn't safe even for humans, in the near short run it kills all other insects as well, including moths, butterflies, lady bugs, etc, and along with it, prey base for insectivorous birds.

Is anyone aware of an alternate kind of mosquito repellant? I have vaguely read about those based on citronella oil and Neel oil etc, but nothing too concrete?

[Sabyasachi Patra]

Citronela oil, Neem oil mixed with any vegetable oil as base would work for sprays. These days people prefer sprays than smoke. However, smoke is easy. Coconut husk which is available everywhere after taking out the coconut, with some resin (called dhoop or jhuna) plus add some neem leaves and when you burn this to kills all mosquitoes. You can even feel the bitter taste of neem. Nothing can be more effective than this. During childhood days we used to use it in our house and in all traditional houses. Unfortunately, now people are more comfortable with these chemicals.

There is a type of mosquito larvae eating fish called Gambusia affinis when released in the drains can be of help. However this species is an exotic species which was introduced in 1928 (http://www.indiawilds.com/diary/indiawilds-newsletter-vol-3-issue-x/) . There are also indigenous species.

PS: In Delhi these days the Government in order to kill off mosquitoes, is using chemical smoke and it becomes difficult to breathe during that time.

[Paramvir Singh]

Thanks for the suggestions. Will try these. Well maintained water bodies with natural diversity will also help.

[Abhishek Jamalabad]

If there is a small artificial water body around that is a mosquito breeding ground, then Gambusia or guppy fish can do the trick. Guppies are available very cheaply from aquarium shops as they are used as food for larger carnivorous aquarium fish. It would not be advisable to release them in a natural water body as they breed exponentially and might overrun any native fauna (if present).

Citronella works well in two forms - as a spray and as an oil in a diffuser. I have used both. The spray is commercially available and works well for personal use or for use in a regular sized room. The diffuser is a more "fixed" method - add a little citronella oil to some water in a small heating container (like a katori) and place this over a small flame (like a candle or a lamp). The water heats up and the oil vapourises slowly (you can start to smell it in a few minutes). Using the diffuser for just about an hour or so in the evening works remarkably well.

However, I think you're looking for a larger scale alternative than a personal or household one. Always, the very best thing to do is to simply keep the neighbourhood clean. :) Bottles, cans, plastic boxes, bags, tyres etc. lying around are a delight for mosquitoes.