34 The Ottawa Naturalist. [May 



where, begin to leave us in August, when there is no sign of 

 cold. And why would they then leave again the warm South- 

 land where there is no cold to be feared at any time ? Some will 

 say: "It is because their food gives out in winter." This is, of 

 course, a better reason than the first, though the two are inter- 

 related. But that even the very important food question cannot be 

 the sole motive for their migrating can be seen from the fact, that 

 many birds start away from here in August and early September 

 when their food is most abundant, and the same can probably be 

 said of the places they leave when returning north. So this point 

 is somewhat mysterious. We have to fall back on instinct, which 

 of course, while being a handy word to use, does not explain any- 

 thing to us. The birds seem to have an instinctive desire for se- 

 clusion during their nesting time, which could not be obtained in 

 the south, where the millions of birds from the north are crowded 

 together with the teeming faunal life there resident. This, toge- 

 ther with the evident love for the place where they were born, 

 seems to be the motive, at least for the northward migration. 

 Besides, we notice an instinct or impulse for migrating in other 

 animals also, as among the lemmings, the salmon, eel, herring, 

 etc. 



Then we ask, "When do birds migrate?" No any one 

 answer will suffice for this question. We have a spring migration, 

 the birds travelling northward, and a fall migration, southward. 

 Each extends over a long time, as some species come and go 

 early, others late. There are probably only two months when no 

 migration of any kind or at least wandering and roving about 

 takes place, these being January and June, the latter the nesting 

 month over a large part of the northern hemisphere. With us the 

 beginning is made in the spring migration by the Prairie Horned 

 Lark and the Crow, which come about the last week of February. 

 During the second half of March come the Song Sparrow, Blue- 

 bird, Robin, Tree Swallow, etc., in April the Phoebe, Kingfisher, 

 gulls, ducks, blackbirds, Meadowlark, etc., but May is the lead- 

 ing month in the spring migration. Then, huge waves of warb- 

 lers, (inches or sparrows, fly catchers and vireos come. The last 

 migrant here is the Blackpoll Warbler, which can be heard into 

 the first few days of June. The fall migration is started by some 



