In early January, I observed a pair of Red-tailed Hawks soaring over a large field in Wrentham, MA. The birds were fairly easy to tell apart, as one had a noticeable gap in her primary wing feathers. Based on size – female raptors are as much as one-third larger than males – I figure that this larger bird is a female, and the smaller bird a male.
The above and below photos capture the mid-air talon drop display of the presumably male bird, which according to the Stokes Guide to Bird Behavior: Vol 3 is a visual display employed during courtship rituals and territorial confrontations. According to Stokes, if the display is territorial in nature, it will be followed by one bird leaving and one bird remaining on the territory. In this case, both birds flew out of view, so I can't say for sure, but I suspect these two hawks are a pair.