Click the links (at the link) for photos. There are a couple that might be what you are seeing.
OS
http://www.examiner.com/article/five-species-of-hummingbirds-that-frequent-san-diego
Hummingbirds can be fun to watch and easy to attract with feeders. They are also good for insect control. In San Diego, there are five types of hummingbirds that frequent the area. Other species visit or pass through the area from time to time, but four manage to stay for any length of time. Two are seen all year around and three are mostly in the area during the summer or on migration.
Anna's hummingbird:
The Anna's hummingbird is probably the best known hummingbird species in San Diego and a year-round resident. They are a medium to medium-large sized hummingbird with a bright magenta or red throat and head on the male who flashes the feathers for attention. Sometimes, the feathers on the chin can appear black when these birds are in the shade or resting. Females are less flashy and green overall with paler bellies, though they may have a small spot of red feathers on their throat.. The male Anna's hummingbird is the only one that is known to “sing” for his mates and territory. He's will sit on an exposed branch, television antenna, or wire and sing with a raspy call.
Costa's hummingbird:
The Costa's hummingbird is also a year-round San Diego resident, but less common except in the desert and coastal areas and not seen in the foothills and mountains at all. They have a feathers that look black, blue or purple throat and chin and on the head. Some individuals also have a distinguishing paler eyestripe that can trail down to the back of the head. They also have a rounder head and shorter body profile than the Anna's.
Rufous hummingbird:
Rufous hummingbirds are often migrating visitors to San Diego, but some do spend the winters here. These birds are said to be constantly on the move, as a species, and never truly have a summer or winter range. This species of hummingbird is easy to distinguish from other local species with their overall reddish-orange and green color. Though they are smaller than the Anna's and Costa's, they make up for it with their aggressiveness. They also have good memories for locating food and can remember where a feeder used to be the last time they visited even if said feeder had been long removed.
Allen's hummingbird:
Allen's hummingbirds can often be confused with rufous because they, also, have a noticeable amount of red-orange. However, males have shiner green feathers on their back and rump and their throats are more brightly red. They tend to visit San Diego on migration, but sometimes spend the summer in the area.
Black-chinned hummingbird:
The black-chinned hummingbird is mostly a summer resident. They look similar to Anna's in shape and size, but their chins are either black or dark purple in the sunlight. They also have a noticeable white or pale belly and a white spot behind the eye which easily distinguishes them from many other species in the area.
So, keep those feeders full, especially during migration times for the chance to see all four species in action.
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