There was a bald eagle raid on the heronry on the Black River in Renton a
few years ago, but apparently the situation has stabilized with the herons
still in place.

Gene Hunn.

On Tue, 4 Jun 1996, Dennis Paulson wrote:

> Don Baccus wrote:
>
> >Since bald eagles are highly territorial during the breeding
> >season, only one pair is likely to ever include a particular heronry
> >in their territory. So, the effect is likely going to depend on
> >the size of the heronry.
>
> I dunno. My guess is that one eagle with moderate ease can cause desertion
> of a heronry of almost any size (although see below). I suppose there
> might well be variation among eagles in their interest and persistence in
> such matters.
>
> >I wonder if herons ever mob a maurading eagle? That would be a sight
> >to see!
>
> It would indeed. Rick Droker told me that when he saw a Bald Eagle eating
> the eggs in a heron nest at Nisqually, the heron advanced on the eagle and
> actually struck at it (from a respectful distance), but the eagle ignored
> it. Apparently the other herons in the colony remained at their nests
> while this particular interaction took place. The observers left without
> knowing whether the event was repeated at another nest, but one could
> imagine an eagle returning again and again with impunity until each heron
> clutch was eliminated. I don't know how many such visits it would take for
> the entire heronry to desert.
>
> I know nothing about the effects of eagles on storkeries, ibisries, and
> spoonbilleries.
>
> Dennis Paulson, Director phone 206-756-3798
> Slater Museum of Natural History fax 206-756-3352
> University of Puget Sound e-mail dpaulson at ups.edu
> Tacoma, WA 98416
>
>
>