Mosquitos tend to adapt to all sprays over time. In our town we have a large population of barn swallows(a kind of bird) that eats mosquitos.
I propose re-introducing mosquitos natural predators...such as dragonflys, bats, swallows, martins etc to the marshes.
Also much can be curtailed by eliminating standing water in uncovered rain barrels, old tires, gutters etc.
We put a little catfish in our horse tank to eat all the mosquito larvae, it works well.
Travis