Yes, while native species of mosquitoes mostly bite at dawn and dusk, the invasive Aedes mosquitoes that are now established in Southern California bite in full daylight.
For a long time, the standard advice if you wanted to avoid mosquito bites was to stay inside at dawn and dusk. This is not the case any more. With the native Culex species, it was good advice. But Aedes mosquitoes do not follow the same rules. They bite in full daylight and often go for ankles with surprising aggression.
Aedes mosquitoes can be split into two groups: the yellow fever mosquito and the Asian tiger mosquito. Both arrived in California over the past fifteen years and are now established across Orange County. You can usually identify them on sight. They are small and dark with white stripes on the legs and body, noticeably smaller than the mosquitoes most people picture. And, as mentioned before, they fly low and target ankles and feet, which makes them extra annoying.
Their breeding habits explain why they tend to show up in yards that never previously had mosquito problems. They can breed in very small amounts of water close to where they bite. Even a plant saucer or the cup of a bromeliad is enough. They will breed in irrigation valve boxes if given a chance, or even a bottle cap. They lay eggs just above the waterline and those eggs can survive dry for months until flooded by rain or irrigation.
That last part matters the most for control. Pouring water out of a container leaves eggs stuck to the sides. Scrubbing removes them. So check the yard weekly and dump and scrub containers that hold water.
As for the adult mosquitoes, that is where mosquito treatment can help. Products are applied to shaded foliage where they rest between meals. When they rest on treated foliage, it knocks them down. This is enough to reduce their presence for about three weeks per visit.
If daytime bites have you avoiding your own yard, Mosquito Squad of North Orange County can help. Mosquito Squad treats the shaded areas where mosquitoes rest and checks your property for the water they breed in. This will help you protect your yard with up to 90% reduction in mosquito activity on a recurring 21-day cycle.
