Since I actually did this work myself (in the US) I am going to go into too much information about my experience. Read the bolded bits if you want the summary of important points without the juicy mosquito-abatement details.
I was checking weekly anywhere we historically found mosquito larvae, including adding new locations any time another location was found—much the same as this program does: using a tablet, satellite map, and gps locations.
I witnessed the larvae populations reducing in response in many places and in other places maintaining a high number of larvae (but no further development stages). It did prevent there from being pupae except if returned to the site late. Pupae are the next stage ( 7-10 days) when the mosquito baby quits eating to morph (and BTI no longer works). As you can see this happens so rapidly that it is important to return to sites weekly and not a day late. Fortunately pupae can also be killed in an environmentally friendly fashion with mineral oil[1]although I rarely (twice per week over ~60? weekly sites in a 7mi2, 35hr a week with recordkeeping, car travel, etc)needed toresort to that.
As mentioned, the biggest obstacle is finding every transient water body, from large to small, and getting people to let you treat their puddles, ditches, water troughs, etc etc etc. I did not scout for new locations although I was encouraged by my employers to ask around for new problem locations. Having an updated map is really helpful but eradication seems unlikely. Another issue is that mosquitoes can fly up to 2 miles (iirc) so if they aren’t breeding nearby they still might by flying in.
Regarding missed locations: I myself skipped some waterbodies when I was scared to trespass. Also water appears and disappears sometimes without much discernable cause, which made it annoyingly important to check empty sites repeatedly. Also obstacles like barb wire fences, and uh… when you are totally alone cattle are really big and I didn’t want to find out if they would suddenly decide to charge me. Instead I kept hoping the next day they wouldn’t be on that side of the pasture.
We loaded up on equipment once every couple of weeks when we ran out of supplies, but I would scan/travel/work closer to 80% of my time. I figured out the faster routes to locations and how I preferred to chain them together through the season. (Although the water does keep moving around as water appears or dries up.) Recording was a simple paper datasheet of larvae/pupae seen and how much treatment I used. I would take a picture at the end of the week to submit so I never had to go visit a central office. And the tablet would track my movements if I might be lying about actually visiting locations. No one ever checked, I’m pretty sure, but if there was a complaint they could. And when working alone it is reallllly tempting to eat 2 hour lunches and skip long, hot, slogs that end in a mostly-dried-up tiny puddle.
They mentioned having much better results when hiring undergrads. I suspect its because undergrads believe they have to be thorough much more than mid-career hires. Also the biology knowledge helps. Honestly I wish they had checked our work more, because I at the end of the season I found out I had been deploying double the treatment what everyone else was. By accident. It was still within permitted doses, but… uh… oops.
In summary: It was highly cheap and effective in the spots I was active. The main issue is coverage of transient water and returning weekly.
Pupae still need to breath. BVA Mineral oil (only a few drops) makes the surface tension at the top too strong for the pupae to break the surface to breath, for about 2-5 minutes. Long enough for them to suffocate. I assume other tiny air breathing species would die too, but not the critters that don’t need air or the slightly-larger critters who can survive longer without air. These are mostly temporary standing-water areas with temporary populations so its likely to be easily repopulated after a suffocation event.
The oil naturally breaks down (from sunlight I think?) and disappears. There was no build up. It looked bad to see shiny oil across natural water but it dissipated in an hour or so, and left no residue. What really convinced me was encountering natural oils in the water from cattails that looked a lot worse than the mineral oil I was using. Oil is a natural thing too, sometimes.
Oil doesn’t work for large bodies of water or flowing water, because the choppy water breaks the oil surface sheet. But mosquitoes don’t live there because they need still water to breed for some reason. Oil is still used in water around the edges of ponds where vegetation keeps the surface still.
Thank you for sharing. I recommend to try “Aquatain AMF” instead of BVA Mineral oil. If you do try, please tell me which one was better in which context
Since I actually did this work myself (in the US) I am going to go into too much information about my experience. Read the bolded bits if you want the summary of important points without the juicy mosquito-abatement details.
I was checking weekly anywhere we historically found mosquito larvae, including adding new locations any time another location was found—much the same as this program does: using a tablet, satellite map, and gps locations.
I witnessed the larvae populations reducing in response in many places and in other places maintaining a high number of larvae (but no further development stages). It did prevent there from being pupae except if returned to the site late. Pupae are the next stage ( 7-10 days) when the mosquito baby quits eating to morph (and BTI no longer works). As you can see this happens so rapidly that it is important to return to sites weekly and not a day late. Fortunately pupae can also be killed in an environmentally friendly fashion with mineral oil[1] although I rarely (twice per week over ~60? weekly sites in a 7mi2, 35hr a week with recordkeeping, car travel, etc) needed to resort to that.
As mentioned, the biggest obstacle is finding every transient water body, from large to small, and getting people to let you treat their puddles, ditches, water troughs, etc etc etc. I did not scout for new locations although I was encouraged by my employers to ask around for new problem locations. Having an updated map is really helpful but eradication seems unlikely. Another issue is that mosquitoes can fly up to 2 miles (iirc) so if they aren’t breeding nearby they still might by flying in.
Regarding missed locations: I myself skipped some waterbodies when I was scared to trespass. Also water appears and disappears sometimes without much discernable cause, which made it annoyingly important to check empty sites repeatedly. Also obstacles like barb wire fences, and uh… when you are totally alone cattle are really big and I didn’t want to find out if they would suddenly decide to charge me. Instead I kept hoping the next day they wouldn’t be on that side of the pasture.
We loaded up on equipment once every couple of weeks when we ran out of supplies, but I would scan/travel/work closer to 80% of my time. I figured out the faster routes to locations and how I preferred to chain them together through the season. (Although the water does keep moving around as water appears or dries up.) Recording was a simple paper datasheet of larvae/pupae seen and how much treatment I used. I would take a picture at the end of the week to submit so I never had to go visit a central office. And the tablet would track my movements if I might be lying about actually visiting locations. No one ever checked, I’m pretty sure, but if there was a complaint they could. And when working alone it is reallllly tempting to eat 2 hour lunches and skip long, hot, slogs that end in a mostly-dried-up tiny puddle.
They mentioned having much better results when hiring undergrads. I suspect its because undergrads believe they have to be thorough much more than mid-career hires. Also the biology knowledge helps. Honestly I wish they had checked our work more, because I at the end of the season I found out I had been deploying double the treatment what everyone else was. By accident. It was still within permitted doses, but… uh… oops.
In summary: It was highly cheap and effective in the spots I was active. The main issue is coverage of transient water and returning weekly.
Pupae still need to breath. BVA Mineral oil (only a few drops) makes the surface tension at the top too strong for the pupae to break the surface to breath, for about 2-5 minutes. Long enough for them to suffocate. I assume other tiny air breathing species would die too, but not the critters that don’t need air or the slightly-larger critters who can survive longer without air. These are mostly temporary standing-water areas with temporary populations so its likely to be easily repopulated after a suffocation event.
The oil naturally breaks down (from sunlight I think?) and disappears. There was no build up. It looked bad to see shiny oil across natural water but it dissipated in an hour or so, and left no residue. What really convinced me was encountering natural oils in the water from cattails that looked a lot worse than the mineral oil I was using. Oil is a natural thing too, sometimes.
Oil doesn’t work for large bodies of water or flowing water, because the choppy water breaks the oil surface sheet. But mosquitoes don’t live there because they need still water to breed for some reason. Oil is still used in water around the edges of ponds where vegetation keeps the surface still.
Thank you for sharing. I recommend to try “Aquatain AMF” instead of BVA Mineral oil. If you do try, please tell me which one was better in which context