red kite standing in water

On Fri 5th Nov I watched a mature red kite standing up to its belly in Maes Llyn pool on Cors Caron at 07:45. It was not moving but seemed relaxed until a farmer came along on his tractor and it flew off. It seems strange that a kite would deliberately wet its under-belly and tail coverts. I remember a similar thing being reported before but the supposition was that it was cooling itself(being summer-time), not applicable on Friday. Any ideas Tony?