Tuesday, April 14, 2015

some local harrier action

in essence the local breeding harriers left last autumn and a pair of new birds moved in this spring and set up a territory; the rufous female from 2014 returned and tried to kick out the young male and female but seemed to be failing then the adult male came back and now it seems as if they have split the area between them but there could still be more action; this sort of thing seems to happen more and more often now as more birds stay the winter but most of the established adult males leave and if they come back late they have to start evicting the squatters;
Plumage variability of Marsh Harriers - British Birds
the paper above is well worth a read and study - baffled, you will be when trying to age and sex birds -- I have long been of the opinion that females in the local population occur in the sort of standard dark chocolate plumage with another rufous morph / plumage occurring infrequently but regularly enough to assume it is not just a one off occurrence -- ageing males on plumage I still wonder about with reference to the above paper but it looks as if they call every bird that is 3cy or older adult which is a bit confusing -- in the fighting shots the young male is the upper bird and the rufous female the lower

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