Even with the pitifully tiny amount of rain we've gotten this year, still there are or could be puddles lurking in your old tires, your plastic mulch bags crumpled in a corner somewhere, your pile of retro/green glazed pottery, your dog's chewed up and forgotten basketball, or those buckets you thought were too good to throw away. These, and even your birdbath can be breeding sites for mosquitoes.
This of course is a male mosquito (likely culex quinquefasciatus but could be a number of other species) . . . with the telltale feathery antennae which are designed to pick up the frequency of the female's beating wings. This leads the male to her, which leads to the inevitable mating, and then blood-sucking (by the female) and egg-laying in one or more of the above-mentioned neglected pools of water. *sigh* The eggs hatch, the larvae develop, pupate and the whole thing starts over again.
How to break the cycle 1) Remove antennae from all male mosquitoes, thus preventing any but the most lucky from mating; 2) Apply DEET to every warm-blooded host (including birds) to stop the female from getting her blood-meal and so stop the development of eggs. Oh, except some mosquito species can produce their first batch of eggs without blood. Well then; 3) Mind yer puddles. Seek out and drain any standing water on your property. Monitor your birdbaths and ponds and if you find wigglers in there, dump 'em out on the hot, dry earth to die; or get some mosquito fish to consume the mosquito larvae for you.
Remember, the itch (or even disease) you prevent could be your own. Thanks from one whose blood seems to be especially attractive to skeeters.