Snail kite building nest

I was taking picture of a couple of snail kites, the male was building the nest while the female was perching on a bush about 20 ft from the nest location. The male will land on the same branch that the female was perching and look for the female "approval". The female will pick up the branch briefly on her beak and the male will fly to the nest location to place the branch.
The interesting part was that one point the female seem to disapprove one branch, she did not pick up the branch and start screaming at the male, the reaction of the male was really confusing, he start flying around with the same branch landing several times on the same branch that the female was perching, until she got tired and flew away.
Is this sound as normal behavior or I am going crazy.

Sounds pretty normal in general Raul (I don't know Snail Kites well at all however). The process of nest building is often ritualised so that the pair bond between male and female is strengthened and they get used to being close together and interacting with each other. In many species the male brings the nest material back to the female as happened here. It is possible that this was a young pair that had not built a nest yet and that the male was showing the female that he was a good provider of, in this case, sticks to build a nest. Maybe the pair was not established yet and so she was being coy. In some seabirds, males fly around or stand in the colony with a "show" fish, basically saying to potential mates "I can catch fish. I'll be a good provider". Maybe Snail Kites do this with sticks??

Having said all this, remember, it is only a theory or an idea and there may be others equally valid out there. Can all the Snail Kite or raptor experts chime in on this one?

I observed the same pair ( I believe) last week. There is a nest, not with eggs yet. Let's say the nest is in area A, and the female is on top of the tree line in area C. The male will fly from then nest in A, to get the branch in area B, between A and C. Instead of going back to A by the short route, which was turning back, he would fly to C and show her the branch. If she approved, then he'd go from C to A, deposit it in the nest and start all over again. Girl power :)
That day she liked all branches, so there was not a problem.
At one point, they came both to the empty nest, where she perched higher in the tree while he fuzzed with the newly acquired branches. Then they would take off together and fly around doing dives, having fun, until the whole process got started again.
I was doing some research on them, and once the eggs hatch, she may leave the male in charge of raising the young so she can find another male and start a new nest, bringing to batches of chicks to the world. I wonder if they sense they are endangered, and try to compensate, like the oranges right before an upcoming freeze, when they get the sweetest and have the most seeds to make sure the species carries on?

John/Fab,
Thanks for the info.
I read the same about the females finding new males after the eggs hatch... Are there more males than females on this species?

Raul