( 89 ) 

 THE LAW OF TERRITORY. 



BY 



J. M. DEWAR, M.D. 



The following note may be found of interest in connection with 

 the " Law of Territory." A male Blackbird [Turdus m. menda) 

 began to sing on March Sth in a range of gardens behind houses 

 on one side of a street in Edinburgh. It became evident 

 that these gardens were his territory, within which he soon 

 established three singing -posts. A female arrived on the i6th 

 or 17th. Thereafter the output of song, which previously had 

 been almost incessant, was much reduced. On the i8th the 

 female spent most of the day in wandering through the bushes, 

 while the male was chiefly engaged on the top of his favourite 

 singing-post — a tall tree stump — in forming a shallow cavity 

 by chipping out the touchwood with his bill. In the intervals 

 of chipping he sat in the cavity and made turning and mould- 

 ing movements, and at length, when apparently comfortably 

 settled in the cavity, performed as if in copiilo. On the 

 following day the female was observed in the gardens behind 

 the houses on the other side of the street, and in the afternoon 

 of the same day the two birds were seen on the ground between 

 the two areas, the male acting as if he were trying to lead 

 the female back to his territory. The female, however, 

 returned to the new territory and subsequently remained 

 there, not being seen again in the first territory. The male 

 followed her lead and acquired singing-posts and a fresh 

 routine in the female's territory. Onl}' rarely did he return 

 to his territory and then only to feed, never to sing. After 

 somQ misfortunes, guessed at rather than ascertained, the 

 pair had fledged young out of the nest in the new territory, 

 and partly feeding themselves by the 26th of June. 



Mr. H. E. Howard and the late Mr. Brock both noted cases 

 in warblers where the females nested outside of, or in extensions 

 of the territories of the males, and the former observed 

 instances of males deserting a territory in favour of a new 

 one. But no case appears to have been recorded of a female 

 rejecting the territory of her mate and on her outi initiative 

 selecting another and presumably more suitable breeding 

 territory, and of a male adopting the territory chosen by the 

 female in preference to his own territory, as happened with 

 the Blackbirds. The territories were quite distinct, being 

 separated from each other by the breadth of the street and 

 the two rows of houses, so that the new area could not be 



