Here is a longer section of that passage from here. Very clever set-up!
From a considerable experience which, through poor equipment, has not yielded adequate return, I am convinced that one may secure excellent pictures of many birds by decoying them with either a mounted or living Owl; doubtless the latter would be preferable, though I have never tried it. With a poorly mounted Screech Owl, however, I have had some excellent opportunities to photograph. My plan is to select some spot where the birds are numerous, preferably near the home of a Catbird, place the Owl in a conspicuous position, and erect near it a “scolding perch,” from which the protesting bird may conveniently vituperate the poor unoffending little bunch of feathers with its staring yellow eyes. The camera is then focused on the scolding perch and the photographer retires to the undergrowth, and, bulb in hand, waits for some bird to take the desired stand.
A Catbird’s domain is chosen for the reason that this species is the alarmist of whatever neighborhood it may inhabit, and once its attention has been attracted to the Owl by “squeaking” or uttering the alarm notes of other birds, the photographer may subside and let the Catbird do the rest.
[…] Other birds in the vicinity are of course attracted, and hasten to learn the meaning of the uproar. Often a bit of undergrowth, of which the Catbird was apparently the only feathered tenant, will be found to possess a large bird population. It is interesting to observe the difference in the actions of various birds as they learn the reason of the disturbance. On the whole, each species displays its characteristic disposition in a somewhat accentuated manner. The Blue-winged Warblers flit to and fro for a few moments and then are gone; the Chestnut-sided Warbler is quite anxious; they Maryland Yellow-throat is somewhat annoyed; the Ovenbird decidedly concerned; the Towhee bustles about, but seems to pay no especial attention to the Owl; the Wood Thrush utters its sharp pit-pit, but is content to let well enough alone if its own nest be not threatened; and the Yellow-throated, Red-eyed, and White-eyed Vireos, particularly the latter, add their complaining notes to the chorus of protests. Not one, however, approaches the Catbird in the force of its remarks, nor does the bird cease to outcry so long as the Owl is visible.