THE OTTAWA NATURALIST 



Vol. XXXII. 



SEPTEMBER, 1918. 



No. 3. 



THE CHIMNEY SWIFT. 

 By Charles M.^cnamara, Arnprior, Ont. 



In general the scientific classification of our native 

 birds seems reasonable enough. For instance, any- 

 one can see the mutual relationship of the ducks, 

 geese and swans included in the order Anseres; and 

 the "hen-like" characteristics common to the turkeys, 

 grouse, ptarmigans and quail embraced in the order 

 Gallinae are very evident. And so it is with most 

 of the other orders. Even the Passeres or Perching 

 Birds, which form the largest division of all, com- 

 prising all the "smalle fowle that make melodie," 

 diverse as the species are in many respects, are 

 joined, most of them, by the manifest bond of song. 



But there is one small order known as the 

 Macrochires, that is calculated to disturb the en- 

 quiring layman by the dissimilarity of its species. 

 For when he finds the grotesque whip-poor-will and 

 the eccentric chimney swift classed with the exquisite 

 humming bird, he is apt to harbour a dark suspicion 

 that the systematist, finding at the conclusion of his 

 labours several aberrant and unrelated forms left 

 over, threw them hastily together into one miscellan- 

 eous order, and called it Macrochires. 



The suspicion, however, would be ill-founded. 

 Different as the birds are in outward seeming, sim- 

 ilarities in their anatomy indicate unmistakably a 

 common line of descent. And if focd habits afford- 

 ed any evidence of relationship, it could be pointed 

 out that the humming bird's taste does not differ so 

 much as is generally supposed from that of its kins- 

 folk, the flycatching swift or whip-poor-will. While 

 popularly believed to live exclusively on nectar, the 

 humming bird in reality consumes large numbers of 

 small insects; and when we see it delicately probing 

 a blossom, it is actually looking as much for little 

 spiders as for flower syrup. 



But analogous food habits are no indication 

 whatever of blocd relationship, although they often 

 bring about astonishing likeness in external appear- 

 ance. The mammalian bat, seeking its prey in the 

 air, has developed wings and attained the bird s 

 power of flight. And the warm-blooded, air- 

 breathing whale, making his living in the sea, is 



always taken by the uninitiated for a fish. But 

 these are extreme cases, and the chimney swift offers 

 a less violent example. This bird is not at all closely 

 related to the swallows (which belong to the order 

 Passeres), but catching its insect food on the wing 

 in sustained flight exactly as they do, it has de- 

 veloped so many of their peculiarities, that not so 

 very long ago ornithologists included it in the 

 swallow family, and it is still very commonly called 

 the chimney "swallow. " 



Swifts are found all over the world, but com- 

 pared with many other like divisions of birds, the 

 family is a small one, including only some seventy- 

 five species. They are all noted for their wonder- 

 fully rapid flight, whence their popular name. But 

 what distinguishes them most among birds is the 

 remarkable mucus secretion of their salivary glands, 

 used by the majority of them in the construction of 

 their nests. Many species merely glue the nest 

 material together with the secretion, but a genus in 

 the eastern tropics (Collocalia) build their nesls 

 entirely of this gelatinous substance. These nests, 

 from which the Chinese concoct their famous bird's- 

 nest soup, are such strange productions that it is 

 hard to believe that they are composed solely of an 

 internal secretion of the bird. An ingenious native 

 explanation of their origin, worthy of our own 

 nature-fakirs, is that the birds obtain the mucilagin- 

 ous shreds by annoying a large holothurian, common 

 along the seashore in the east and known as a sea- 

 slug, until the exaspera'ed creature throws out long 

 slimy strings at them, which they gather up and 

 carry away for their nests. The less picturesque 

 but equally incorrect theory of Western science was 

 that the nests were mostly composed of partially 

 digested seaweed. It is now known, however, that, 

 leaving out of consideration some edventitious dirt, 

 the nests of this genus consist of practically nothing 

 but mucus. 



About one-half of the known species of swifts 

 are natives of the New World, but most of them 

 are confined to the southern continent, only four 



