Scott Gregg Beaver Falls, PA In thirty years of observing both ospreys' and eagles' nests, I've never seen their nest site preferences overlap. The one, ospreys, seem to build nests in the most extreme exposed locations, and the other, eagles, seem to prefer more protected locations (trees with foliage). Admittedly, most of my observations have taken place in PA and MD, with only a few in extreme eastern Ohio. I've only ever seen one eagles' nest on a man-made structure, a high-tension tower. Furthermore, the nest on this structure was placed mid-way down the structure, and the nest was never successful. In contrast, all the osprey nests I've seen are on the very top of a structure. They seem to prefer the most extreme, exposed nesting sites. Maybe this is not the case with these birds in Ohio.? I witnessed eagles taking over a red-tails' nest location and building upon the nest. The nest was in the vicinity of water, but the situation was not good -- I don't think the eagles were experienced nest builders (The female was a fourth-year, first breeding year bird.). The nest was not in a very substantial crotch - it appeared that either the weight of adding to the nest and/or a good windstorm would bring it down in pretty short order. Typically, they were not successful in their first breeding attempt, and they did not return to the site in the following year. It seems the same would be true of them building on a herons' nest - very poor location, the top of a tree with very little substance to support the nest. I consider the osprey an "all bark and no bite" bird. I've only ever seen them threaten (vocally) other raptors or make a few half-hearted dives at other raptors, always maintaining a safe distance. As someone else mentioned previously, they breed and raise their young much later in the season than other raptors. Has anyone actually ever witnessed ospreys usurping or using another raptors' nest site? ______________________________________________________________________ Ohio-birds mailing list, a service of the Ohio Ornithological Society. Our thanks to Miami University for hosting this mailing list. Additional discussions can be found in our forums, at www.ohiobirds.org/forum/. You can join or leave the list, or change your options, at: http://listserv.muohio.edu/scripts/wa.exe?LIST=OHIO-BIRDS Send questions or comments about the list to: [log in to unmask]