Swans mucking about - too much testosterone?

I consider myself really lucky to be able to watch various water birds doing their stuff just a short walk from work so very "do-able" in my lunch break. This is in the middle of a small market town and the birds seem not to mind the pedestrians, most of whom completely ignore the birds, relying on just a modest percentage to throw whole loaves into the river to "feed the ducks - aaah"

These boys have been pulling each other about for the past few weeks.

Canon EOS-1D Mark II, either 70-200 + 1.4 extender or 100-400L, @260.0mm,

Exposure Time: 0.0005 s (1/2000)
Aperture: f/5.6
ISO Equiv.: 400
Exposure Bias: -0.33
Whitebalance: Auto
Metering Mode: matrix
Exposure: shutter priority (semi-auto)

WDYT?

Could be an advert for underwing deoderant. Nice behavioural shot.

a interesting shot Pete but lacks real impact if I'm honest. A lower POV and greater interaction between the swans may help, but not easy I realise.

Matt