BLUE-GRAY GNATCATCHER 355 



at some distance the observer has no difficulty in recognizing a gnat- 

 catcher in flight, while chickadees, kinglets, and small warblers pass 

 unnamed. P. A. Taverner and B. H. Swales (1908) gave an idea of 

 the capabilities of this species for performing sustained flights when 

 they listed it among the migrating birds on the southward crossing 

 from Point Pelee, Ontario. The gnatcatchers they saw were unable 

 to face the heavy wind prevailing at the time of the observation, and 

 had to come back ashore, tacking just as a man would do in a boat, 

 but the inference was that, under favorable conditions, the crossing 

 would be completed successfully. 



Certainly the most expressive feature of the gnatcatcher — as of its 

 larger counterpart, the mockingbird— is its long, ever-active tail; now 

 up and down, now from side to side, it is never for an instant at rest. 

 Under stress of great excitement, the bird seems to try to combine 

 these two motions at once, and achieves a ludicrous impression of 

 circular motion. 



The gnatcatcher's manner of feeding is similar to that of many 

 other small birds, yet it differs in some respects from the methods 

 employed by its most frequent associates even though its food, in 

 winter at any rate, is probably the same as theirs. In its gleaning 

 of the twigs and leaves of trees and bushes it tends to maintain an 

 upright position and never (as I recall) hangs beneath a twig, as is the 

 chickadee's constant habit. Like the kinglets, it often hovers before a 

 leaf or terminal twig to secure some morsel that cannot be reached 

 from above, but it does not indulge in this habit with the frequency 

 of the kinglets. Unlike the creepers and the nuthatches, it is seldom 

 or never seen on the trunks or large branches of trees. It is adept 

 as a catcher of flying insects (many other kinds besides gnats!) and 

 even in winter is often seen to secure food in this way. Its darts 

 after flying insects differ markedly from the long swings of the true 

 flycatchers, for its forays are seldom more than five or six feet in 

 extent and are usually vertically upward with a quick drop back to 

 the starting point. Again, unlike the flycatchers, it does not perch 

 motionless and wait for passing insects; and I suspect that much 

 of its catching of flying insects is by way of retrieving prey that, 

 disturbed by the bird's actions among the leaves, makes a sudden 

 flight to escape capture. Rarely, when the gnatcatcher is feeding 

 in low bushes, it drops momentarily to the ground to pick up some 

 object that attracts its attention; but it is no sense a ground feeder 

 for it does not search for food while it is on the ground. 



Field marks. — The blue-gray gnatcatcher, one of our smallest birds, 

 can be distinguished from all other very small birds of eastern North 

 America by its clear blue-gray upperparts and unmarked white under- 

 pays entirely lacking in yellow or yellowish tints, especially when the 



