The Front Range urban corridor stretches along the western edge of blue jay breeding territory in North America. West of here, in the foothills and mountains, they are replaced scrub jays, Steller's jays and gray jays.
Since we purchased our Littleton farm, in 1990, blue jays have been common visitors on the property though I have never observed nesting activity here; on bird counts of the farm, a couple of blue jays would generally make the list. During my current visit, however, blue jays have been especially common, their raucous calls and musical trills echoing across the farm; indeed, their numbers have been second only to house finches (which have long been our most abundant avian resident). Since some blue jays do migrate southward for the winter, our current visitors might reflect that fact (though they have stayed for almost two weeks).
Like many songbirds, blue jays form flocks during the colder months but their numbers here seem exceptional compared with past years. My guess is that this influx is an adaptation to suburban sprawl and "development" in Metro Denver, forcing the jays to gather in or near the dwindling areas with large trees: at parks, along greenbelts and near the few old farms that still exist.
