National Geographic : 1954 May
686 Camera Flash Catches an Owl's Eyes Oddly ill-matched pupils result from a speed flash f The bird's left eye, closer to the flash, contracted muc (page 684). This Screech Owl, photographed near Trun the same apple-tree dweller shown in color on page 68 filled the food trays in front of the speed lights with "cheese cake," as we called it, diligently baked by Mrs. Stuart according to the formula devised by Mrs. E. D. Morton, of Tucson, as the one most alluring to Arizona birds.* Once the birds were accustomed to the gen eral setup, we could get into either of the two blinds and plan ways of arranging perches or accessories so that the birds would pass, at least momentarily, through the plane of focus of the waiting cameras. Ingenious electric eyes have been designed by Mr. Crawford H. Greenewalt, of Wilming ton, Delaware. Mr. George Blake Johnson, of Framingham, Massachusetts, and others to activate shutters at the exact instant when the bird lasses through the plane of focus and is in the center of the film. Mr. Stuart, how ever, an old-time duck hunter, prefers to give the birds a sporting chance by matching his reaction skill against the varying speeds and angles of their flight, and I was glad to join him in this sport. Of course we occasionally cutoffaheadoratail through misjudgment, but that merely piqued our interest and stimu lated our competition in this fascinating game. Many Nests Guarded by Cactus Spines It was the last of March when Mrs. Al len and I arrived at the Stuart home, but only a few of the birds had started nesting, among them the Palmer's thrashers, brown tow hees, and cactus wrens. Like other wrens, cactus wrens have the habit of building dummy nests, or "cock Off Balance nests," to mark out the ired 15 seconds earlier, territory which the pair h more than the other is ready to defend. In mansburg, New York, is one of these timmy 5. one of these dummy nests the male usually spends the night, going to bed somewhat earlier than the busy female. It is not always easy to determine whether a nest is occupied or not, for many are built in the cholla, or "jumping cactus," where it is impossible to insert one's finger without having it impaled on at least one of the sharp spines. Likely as not, the whole joint of the cactus will then break off and remain attached to your finger. When you try to remove the spine, a finger on the other hand becomes impaled on the opposite side of the same burr. Then you must hunt a real friend-or perhaps two-to release you. * A mixture of 4 parts cornmeal, 1 part flour, 2 parts suet, and 2 parts sugar, boiled to the consistency of a thick mush.