SIDE LIGHTS ON BIRDS 



accommodation, to betake themselves to a nearby- 

 wood, and so, in a double sense, to form a branch 

 colony of their own . 



In Mr. Eliot Howard's " Territory in Bird 

 L/ife," the idea is worked out at considerable 

 length, that most birds map out definite areas 

 that they claim as their own, and that the instinct 

 for separate domains has a wide bearing on the 

 facts of migration, and on the behaviour of the 

 different species as the breeding time draws near. 



It is argued that, in the case of immigrants, 

 the male birds often reach this country in ad- 

 vance of the females, just at a time when the 

 sexes might naturally be expected to remain to- 

 gether, and that they do this to peg out their 

 claims to the area they regard as their own. 

 Further, that when the domain has become es- 

 tablished, the female is just as ready to defend 

 it as the male is, and that many of the bird- 

 battles to be seen in spring, are not, as is sup- 

 posed, so much matters of sex rivalry, as of 

 guarding the rights of property. 



Although we cannot follow the author in all his 

 inferences, the numerous observations he has 

 made bearing on the matter have a distinct 

 value of their own. There is no doubt that the 

 red-grouse, although this case is not cited, claims 

 a definite tract of heather as its nesting site, 

 driving away all encroachers, a habit becoming 

 more marked as it grows older and more formid- 

 able. Thus the moor-keeper is aware he can get 

 a large number of nests in close proximity when 

 the old cocks are killed off by driving. 



Again, we can fairly de-limit a robin's domain 

 by putting down a decoy, for if the area has been 

 appropriated, the owner will almost instantly 

 appear to assert his rights. Personally, we al- 

 ways attributed this to the inborn pugnacity of 



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