igio. Revieiv. 249 



Mr. Kirknian has occasion, under the head of nearlj' every species, to 

 refer to evidence showing the existence during the breeding season 

 of a large number of adult unpaired birds — a fact of which he holds that 

 no satisfactor}' explanation has yet been tendered. Referring to the 

 suggestion broached some years ago in this Journal (vol. xii., pp. 158- 

 160), that the habit the birds have of parcelling out the ground into 

 nesting areas is the main cause, he objects that in the case of persecuted 

 species like the Crow, Jay, and Magpie, the nesting areas are obviously 

 much in excess of the pairs. Though this may be locally true, it seems 

 at least open to doubt whether it is true of those parts of our islands in 

 which the existence of large numbers of unmated birds chiefly calls for 

 explanation. Mr. Kirknian himself seems scarcely to realise how 

 common a bird the Magpie is in Ireland, for he tells iis that " in this 

 country " — meaning apparently the British Isles generally — Magpies- 

 nests "are not often seen, owing to the comparative scarcity of the 

 species," but that the}^ *' are a familiar sight in many parts of the Con- 

 tinent." Of course a great deal depends on the size of the area which 

 each pair thinks right to appropriate to itself. Speaking of the Chough? 

 Mr. Kirkman seems disposed to accept the view that unpaired birds of 

 that species seen in spring in the Isle of Man (Ralfe, " Birds of the Isle of 

 Man," p 84), are individuals which have failed to secure nesting sites, 

 owing to the resentment shown b}'' the breeding Choughs at intrusion 

 within their domains ; and he quotes as supporting this view Mr. 

 Ussher's statement (" Birds of Ireland ", p. 84^, that Choughs' nests along 

 suitable parts of the Waterford coast "occur on an average a mile apart." 

 This is very considerably in excess of the average distance between twa 

 Magpies' nests in the better wooded parts of Ireland 



Mr. Kirknian is disappointingly meagre in what he says of the gifts of 

 mimicry possessed hy most of the Corvidse, but in a special degree by 

 the Jay. It does not seem to be realised how habitually the birds make 

 use of this gift during the latter part of their breeding season. Mr. 

 Kirkman quotes one instance (Durban and Matthew, " Birds of Devon- 

 shire ", p. 87), in which a pair of Jays exercised their mimetic powers 

 when scolding an intruder who was examining their young — "now 

 cawing like a rook, then mewing like a cat, and in their extreme 

 agitation actually plucking off leaves, and biting off pieces of dead twigs 

 from neighbouring trees." All these actions — and especially the imita- 

 tive ones — are habitual with Jays when they have young, so much so 

 that the reviewer has sometimes been scolded in precisely the same way 

 by as many as three pairs of parent Jays at different stages in the course 

 of one walk through an Irish wood The notes most constantly repro- 

 duced on such occasions in Co. Wexford are those of the Magpie, Cat, 

 Blackbird, Squirrel, Sparrow-Hawk, and Hooded Crow. The obvious 

 intention of the old birds is to lead the intruder to imagine that he is 

 being threatened by a much larger number of creatures than are actually 

 present; and the fact that practically the same set of cries— though 

 with different degrees of frequency— are reproduced by every pair of 

 parent Jays whose haunts are intruded on shows how largely the 



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