I usually have birds act their most aggressive when nests and or young are around (I have the scars on my scalp to prove it) but I have seen them mob/attack herons, hawks, sub-adult gulls without necessarily defending a nest or young. Probably just a natural defense response. We had an osprey fly close to Popasquash today. There were about 30 terns on him/her in a flash. It didn't stay long.
As far as the possibility of a nesting attempt on Arrowhead, it seems unlikely though not necessarily out of the question. If they did they probably would not have set up shop so close to nesting osprey.
Director of Conservation
255 Sherman Hollow Road
Huntington, VT 05462
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From: - Maeve Kim [mailto:[log in to unmask]]
Sent: Monday, August 11, 2003 2:52 PM
To: [log in to unmask]
Subject: Re: Terns and such
No, Mark. We saw either two or four terns (the same pair twice or two pairs)
and all were adults. We watched a pair dive bomb and harass nesting osprey for
about twenty minutes - behavior that appeared to be just "fun" for the terns.
(There were two successful osprey nests, one on a man-made platform and one
quite low to the water - maybe six to eight feet - on the spreading roots of an
old fallen tree. Each nest had an least one good-sized chick. The bird in
the tree-root nest did a lot of stretching its wings and looked fledge-able.)