Jonathmartinez

the underwing pattern of the outer primaries fit well for Western Mars Harrier (note the limited pale area at the base of the outer primaries), but the head pattern and the yellow streak on breast suggest that it is not a pure bird and probably have some Eastern Marsh Harrier origin as well. Nice looking bird...

Jonathmartinez

yes exactly, but the situation is very unclear especially about which features is reliable or not to exclude any hybride, maybe some of the features especially about head pattern and streaks on breast are just a case of moulting issues. The underwing pattern suggests that this bird has strong Western Marsh Harrier influence, and it could be possible that this bird is simply just a Western Marsh... As Paul said, good pictures showing the rump may be of great help to better document this bird.

Jonathmartinez

the broad and pale tip on one of the uppertail covert is probably indicating some Eastern Marsh origin as well, on a pure Western I would have expect uniform brown or with a slight rufous tip uppertail covert but not as contrasting as on this bird....So an Hybrid to me...