When I was taking care of mom 2 years ago, she had a few come to her lilac bush. She decided they needed "fattening up" for the winter and we had go shopping for feeders. We got some and mom made the sugar solution for them, but she made it super-sonic! She dissolved a 5 lb bage of sugar in about 2 gallons of water. Anyway, she had fights going on at the feeders everyday! We loved watching them chase each other.
Here's a few pics of mom's hummingbirds (I can't wait to get my landscaping done, I miss them!).

Lone male, I guessed male b/c of the colors.

I think this was a female, dull/gray colors.



This was a daily crowd fighting over the feeders. These pictures are small, it's difficult to see, there's 3 birds at the feeders.

This fight lasted over 2 hours. They chased each other non-stop. I could not believe how loud hummingbirds can be!