Bird Journal

May 19


Simply sitting out on the back deck the sky this time of year looks something like a sunny aviary airport.  Researchers now know that birds navigate not by any one sixth sense but by a very complex unified combination of sensory mechanisms.  Birds have tremendous sight and as they fly from nest to feeding zones they take visual snap shots of the various landmarks in landscape.  Take a precocious migratory bird from nest several miles away and they will find home by utilizing those burned images.  Birds can smell their particular region as well; various regions contain various flora and fauna and birds can follow those senses as well.  Also built into the main frame of the bird is an ability to detect thermal transitions and flows of the earth and wind patterns so that we could easily imagine a bird, high above in a flock, literally feeling the surrounding area getting warmer as it makes its great journey from Canada to the Midwest, for example.  The backyard aviary airport, then, indicates that birds find good foliage here, good housing sites, and most importantly they think its warm enough to safely start flitting about with nest morsels.  Besides the hawks, warblers, vireos, orioles, robins, two mallards, the cardinal and the hummingbird, it was the case of the elusive Eastern Bluebird that was most interesting in the backyard stage presentation as what looked much the golden breasted but blueish winged bluebirds landed on the top gutter of the house and looked down on us as though we were the intruders.  We binoculared and still the colors matched to what we thought was that of the bluebird yet, as it took off its wing pattern seemed longer and more prongy at the tail.  We matched the online birdcall with what we were listening to.  No such luck.  The common barn swallow, although quite dramatic in its own right, had been swooping aggressively across the

backyard skyline swaying off any foreign intruders like people...much in the same way the red-winged blackbird likes to harass the crows back up into their bluffside trees.  It is said of the barn swallow that they have become one of the most common users of manmade nesting sites of all the birds, very rarely seen any longer finding homes in trees or bushes.  The bluebird, by contrast, is very particular about their homes, needing a certain height, space and slight opening in the field or grassland.  Their old nemesis, the common swallow, likes the same thing and they often have to fight it out.