Hummingbird Migration in Full Swing

The number of hummingbirds observed in the Colvin Run Habitat this past summer was disappointing. I believe that the low numbers was due to the drought currently being experienced in the mid-Atlantic states.However, beginning the third week of August the number rose dramatically. Instead of seeing a hummingbird once a week, several were observed every morning and evening. The observed hummingbirds were clearly distinct as they were of different sizes. The hummingbirds are most likely passing through on their way to Central America for the winter.
I have never observed hummingbirds as aggressive - they not only chased each other from the feeders, but they also chased other birds - finches, titmice, and on one occasion a cardinal. These photos were taken as the sun came up one morning.This female (third photo-no red throat as in the male below) made a rare mid-day appearance. After she shared the feeder with a bee interested in the sugar water, she perched on the dogwood and posed for me (first two photos). I was able to approach to within ten feet.
This male paid a more typical sunrise visit. The low light of the early morning is the reason for the poorer photo quality of the last two photos.
Remember that these birds are about the length of an adult human's ring finger.