I've visited the traditional nest site of yellow-crowned night-herons in east Columbus a number of times this year, and heard reports from any number of other observers, including local residents. It was quite obvious that beginning on 6 April when they first appeared that only three adults were present, and so it has remained, apparently. A pair promptly nested in one of the existing nests, and the third bird hung out at the other one. The nests were in the same large sycamore. The active nest, SE of the other one and over the east curb at #211, produced a nestful of young [this colony of two pairs usually produces 4-5/nest] during May; leaf cover and viewing angles made it hard to tell, but it seemed at least four young were hatched. None had been noted earlier at the other nest, over the middle of Preston Rd. Recently some observers have reported that this neglected nest was newly active. Some speculated that the disappointed adult was a female who was eventually impregnated by the male from the other nest, because in recent weeks both nests have had young in them. Based on the apparent ages of the young, I doubt this hypothesis. I don't know, but today we went to the site and saw three or more young birds--at least one in the 'new' nest and two in the 'old' one. It was hard to tell how many were there in all, but they all appeared to be of a similar size and age. Only one adult was present, at the 'new nest," but the other adult(s?) could easily have been away foraging for food. In past years, the young night-herons have quickly grown enough to fly shortly after the fourth of July, and these birds looked pretty much fully fledged and of the right size. It looked to me as if one or more of the four or more young in the first nest had moved to the second one; this certainly would have given them more room. Perhaps all three adults remained to feed them. The previously unused nest was smaller but in a lot better shape than the old one, which was sagging and seemingly falling apart. All of this poses questions: --how cooperative are YCNH at communal nest sites? Will odd unmated pairs/individuals feed the young of mated ones? [in past years, year-old immature birds have arrived with the adults and seemed to act as helpers, but not this year]. Will they cede territory in an unused nest to allow successful pairs to use them? --will unmated YCNH remain at a nest site through the breeding season if a mate does not appear? Will an unmated female accept impregnation from a male from a nearby existing pair? How might they be distributed over two nests? --has anyone seen four adults at the Preston Road site this year? Has anyone seen more than five young there this year? Our situation here, with two pairs showing up year after year after year, provides a unique opportunity to answer these questions. It would be very interesting to know the answers, and careful observations are requested. Bill Whan Columbus p.s. yellow-throated warblers were singing lustily at this site today. ______________________________________________________________________ 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]