1^17] The Ottawa Naturalist. 75 



starvation, the lack of food being due in its turn to a scarcity of 

 ground squirrels (gophers) and to the unusual number of hawks 

 nesting in the district. 



The curious habit of the old birds in gathering a green leafy 

 bough and placing it in the nest, characteristic of Swainson's hawk 

 also, is very marked in the Red-tail, a fresh bough being gathered at 

 least once daily during the time when the young are small. There has 

 been some doubt hitherto as to the cause of this habit, but by observing 

 the nestlings I am led to believe that the bough acts as a sun shade, 

 as the young have been seen to repeatedly pull the bough over them- 

 selves and crouch beneath it. Doubtless it also acts as a shield and 

 hides the young from their enemies. The leaves arc also occasionally 

 eaten. 



As the young develop they acquire a good deal of boldness and 

 defend themselves with both beak and claws. They have a habit of 

 closely watching the intruder backing up meanwhile at the 

 approach of a hand; then suddenly the) leap forward with wing- 

 outstretched and it requires a rapid movement to escape their on- 

 slaught. The old birds make no efforts to defend their young, but fly 

 high overhead uttering loud cries which are, at times, answered in a 

 shriller key by the young beneath. In the fall these birds may be 

 seen resting upon trees and telephone posts, looking very un-Red-tailed 

 in appearance and superficially very like the young of Swainson's 

 hawk. Towards the middle of October they make their way steadily 

 southward and by the end of the month have practically all passed 

 beyond our borders. 



The food habits of hawks have been discussed on many occasions 

 and the examination of stomachs by Fisher and others in the United 

 States show^ that all our large buzzard-like hawks, such as the Red- 

 tail, Rough-legged and Swainson's hawks, are extremely useful. 

 In discussing these from the standpoint of the prairie farmers, how- 

 ever, we have to take into consideration the fact that the prairie pro- 

 vinces are largely grain producing. Secondly, that they are infested 

 by several species of ground squirrel which are quite unknown in 

 eastern ( anada and winch take heavy toll from the grain fields. Thus 

 our problems in regard to hawks are quite unlike those of the east 

 and it seems a mistake to unite these in an article of this sort. 



As the Red-tailed hawk is more an inhabitant of woodlands than 

 the other species mentioned above it naturally follows that it is not 

 so much a hunter of the plains, hence the prairie ground squirrels do 

 not form so large a proportion of its food. They are, however, taken 

 in quite large numbers and are supplemented by wood-loving kinds 

 such as Franklin's ground squirrel, the common red squirrel and by 

 mice. The food habits are also much more difficult to ascertain owing 

 to the thorough manner in which the parents clean up the nest and to 



