I'm thinking that ponders actually help the
mosquito problem rather than contribute to
it.
A pond with fish, or a pond treated with Mosquito
Dunks, is like a trap. Mosquitoes laying eggs
are in danger of being eaten by the fish or the
dragon and damselflies that the pond attracts
(and the toads and the frogs, too) and their larvae will
most certainly be eaten or in a fishless pond they
will be taken out by the Mosquito Dunks bacteria.

So by keeping ponds we are luring mosquitoes to
their doom. Without that pond there the mosquitoes
will lay their eggs in abandoned bits of water laying
around or in bigger waterways where the amount
of water to fish is much larger and they have a chance
to escape.

Our garden ponds are way overstocked compared
to Mother Nature's ponds and waterways so they
much better at reducing the mosquito population.

k :-)