Mosquito Control Questions

Pre Strike torpedo and live larvae

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I have used PreStrike Torpedoes for years and have never had a problem. This year , because of the drought, I have been using muck buckets for water, and so the water is changed completely every week at least.

However I put torpedoes in two tanks I no longer used, that had 8 to 10 inches of water still in them, thinking these would attract the mosquitoes and then the larvae would die. But today, 5 weeks later, I suddenly noticed larvae wriggling about, coming to the surface and going back down. I scooped up some, and they are more transparent and a kind off lightish green rather than black and perhaps a bit smaller than the black ones I am used to seeing in other years. I tried coating the water of one tank with a whole bottle of sunflower seed oil, but I can see that every once in a while, one larva swimming up, is not discouraged and finds somehow a spot where he must be able to get air. I am going out to find the strongest of Chlorine bleach. I know that bleach, even full strength does not kill them, but I just read that most bleach is not strong enough. If that does not work, I thought I could spread a big piece of black plastic in a large hollow and pour a very thin layer of the infested water into that so that it will evaporate and kill them ?? 1) can they live once dried out ? 2) What else can I do? 3) What happened? Why did the torpedoes not work this year ? Thank you, Polly du Pont

Verified Answers
  • Polly,

    The PreStrike Mosquito Torpedoes have an active ingredient of s-methoprene, which is an IGR (insect growth regulator).  The IGR is a synthetic insect hormone disrupts the insects life cycle by making it impossible for larvae to complete development.  Because of this, you can have live mosquito larvae since s-methoprene is not an insecticide.  The live larvae ingest the s-methoprene, which stops their bodies from successfully transitioning into adults.  So while you may see live larvae, they will not become adult insects, instead they will either wither and die as larvae or try to transition to the pupal stage where they will die.

    As for your other questions, if you dump the water out of the tank, the larvae will die quickly.  Mosquito larvae cannot live without water.  If you don't like seeing the larvae, the best option is to dump the tank (save your Mosquito Torpedo), which will kill any living larvae.

    If you have any other questions, please let us know.

    Thank you,


  • Hi Jessica, I had pretty much come to the same conclusion, as I could see that I still had the same number of larvae ( in a smaller control muck bucket) and that mre and more of them fell to the bottom, clearly dead. Thanks for your answer. I guess I was just seeing the middle of the cycle..It is such a relief to have something that WORKS Polly

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