Blowflies can indeed be a problem. We've not encountered that here but it was more common in Maryland back in the 70s. At that time, a dusting with SEVIN worked well. House design is somewhat akin to mousetraps - someone always has a new design but the basic works best.
There has always been controversy over the frequency of Bluebird house visits by its stewards. Some contend that cleaning the house in spring suffices while others closely monitor each house on at least a weekly basis. With that in mind, we were asked by Larry Zeleny (father of the NA Bluebird movement) to design a research project during the time I was a board member. We did that and after two years reached several significant conclusions. This was all in Md and may differ up here. We found that human interference (in our case monitoring and banding) during breeding season contributed to greater nest predations, particularly by Raccoons and Black Snakes. The assumption is that these predators leaned that a human scent trail meant potential food. Snakes were particularly adept at defeating all manner of predator guards. As a result we ceased all nest box visits other than the original clean out. We also ceased banding nestlings and extended that to American Kestrels as well. Visual observations by a large group of volunteers showed a marked increase in production by the bluebirds. A sidelight of that study showed that boxes placed very close together and even on the same pole hosted different species without apparent confrontation. This was true for both Carolina Chickadee and Tree Swallow. Best, John -- John and Sue Gregoire Field Ornithologists Kestrel Haven Avian Migration Observatory 5373 Fitzgerald Road Burdett,NY 14818-9626 Website: http://www.empacc.net/~kestrelhaven/ "Conserve and Create Habitat" -- Cayugabirds-L List Info: http://www.NortheastBirding.com/CayugabirdsWELCOME http://www.NortheastBirding.com/CayugabirdsRULES ARCHIVES: 1) http://www.mail-archive.com/[email protected]/maillist.html 2) http://birdingonthe.net/mailinglists/CAYU.html 3) http://www.surfbirds.com/birdingmail/Group/Cayugabirds Please submit your observations to eBird: http://ebird.org/content/ebird/ --
