Another interesting observation; BHG frequently show a rosy flush, my feeling is particularly in breeding but from my records from Dec onwards; Olsen mentions for BHG (p438,439) but does not seem to identify seasonal variation - however, same is mentioned there for Franklin's "underparts white with pinkish tinge, generally strongest in spring" (p516). Ross's is also "less rosy-tinged" in winter (not that I would know!), Olsen p555. No doubt other hooded gulls the same.
Coming to case in point, Common Gull, I have one record of a rosy flush individual, Seton Sands 4/3/07; I can see no reference to this in Olsen. I do not recall any apricot gulls of any sort! I guess all of these are ultimately diet-related, though it seems unlikely it is just a coincidence there is a stronger flush in *breeding season* for at least some hooded gulls - there is a correlation then with the deeper bare parts colours.
A final tangential comment, I recall a Herring Gull with yellow legs at Seton, 11/3/06, this bird also had a very bright yellow bill and I recall reading of the same correlation in a subset of Baltic Herring Gulls, also cited in Olsen as a proportion of birds occurring in Denmark (5-20% Feb/Mar, p260).
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Another interesting observation; BHG frequently show a rosy flush, my feeling is particularly in breeding but from my records from Dec onwards; Olsen mentions for BHG (p438,439) but does not seem to identify seasonal variation - however, same is mentioned there for Franklin's "underparts white with pinkish tinge, generally strongest in spring" (p516). Ross's is also "less rosy-tinged" in winter (not that I would know!), Olsen p555. No doubt other hooded gulls the same.
Coming to case in point, Common Gull, I have one record of a rosy flush individual, Seton Sands 4/3/07; I can see no reference to this in Olsen. I do not recall any apricot gulls of any sort! I guess all of these are ultimately diet-related, though it seems unlikely it is just a coincidence there is a stronger flush in *breeding season* for at least some hooded gulls - there is a correlation then with the deeper bare parts colours.
A final tangential comment, I recall a Herring Gull with yellow legs at Seton, 11/3/06, this bird also had a very bright yellow bill and I recall reading of the same correlation in a subset of Baltic Herring Gulls, also cited in Olsen as a proportion of birds occurring in Denmark (5-20% Feb/Mar, p260).
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