|The Big Pond in which the dogs like to stand (and drink).|
|This one's good only for drinking from.|
I have at least two Water Features in my yard (that is to say, I have two intentional water features in my yard. Who knows how many nooks and crannies that I'm not thinking about are harboring ponds of fugitive mosquito larvae).
My dogs happen to like the water in my 2 ponds. They mostly just drink from the waterfall, but Tika and Boost in particular like to actually get into the bigger pond, even though I keep it not all that deep. (Used to try to keep it empty, which was impossible in the rainy season and challenging during irrigation system, but now that I know that they like it, I'll try to keep some water there.)
So using mosquito fish doesn't seem practical; I'm sure they'd be a game for the dogs until the dogs had managed to do them all in. Bti is supposed to be pretty much harmless for mammals (I'm not sure I'm fully confident about the "pretty much" part, but then chlorine, which is used all over the place, doesn't even pretend to be pretty much harmless) but it's a bacterial agent that lasts only 24-48 hours per application, and sure, like I'm going to do that all the time. I don't know how much it costs per dose.
I contacted Santa Clara County Vector Control and the woman to whom I spoke confirmed that actually having the water move even a little bit every day is an effective control. But pumps and spouts enough for a pond of the big one's size can be over a hundred bucks, not entirely in my budget. The smaller one's waterfall runs for an hour every evening, and she said that's way more than sufficient.
But she also said that simply using a swimming-pool net to scoop out the mosquito wigglies is quite effective. And since I do that on a semiregular basis to keep out the leaves and other debris, I'll just be a bit more diligent. If the pond were much deeper, it wouldn't be practical, but at probably 6 to 8 inches or less, this can be accomplished.
But I also apply a wee bit of cholorine to try to keep the algae and stagnant odors down. I don't know how harmful that could be. I suppose I ought to research that, too. I tried some organic stuff that's suppposed to be safe for wildlife and keep the pond clear, but it didn't appear to do anything for me at all.
All to keep the doggies happy!