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MARKING BIRDS. 



THE "BRITISH BIRDS" SCHEME. 



References to the plan of marking birds have been 

 made from time to time in previous numbers of this 

 Magazine, and the subject will be familiar to our readers. 



The results achieved by Herr C. Mortensen in Denmark 

 and by the officials of the Rossitten Bird Observatory in 

 Germany (c/. Vol. II., p. 362) prove that the plan is 

 well worthy of a thorough and exhaustive trial. 



If sufficient results were obtained much could be 

 learned from marked birds. We should gain a more 

 exact idea of the movements of individual birds than has 

 ever been possible by any other method, and this should 

 not only throw light upon the more general aspects of 

 migration, but it should tell us a great deal that is at 

 present obscure with regard to particular points. For 

 example, while we may know the general distribution of 

 a species in winter and summer, we do not know the 

 extent of the migration of individuals ; or, indeed, whether 

 in such cases as the Song-Thrush and Robin, certain 

 individuals migrate at all. The movements of sea- 

 birds are very little understood, and much might be 

 learned from marking a large number. This plan might 

 also tell us what influence age has upon plumage, etc. ; 

 where a young bird, whose birthplace is known, breeds ; 

 whether individuals return to previous nesting haunts, 

 and whether pairs come together again in successive 

 breeding seasons. 



Such are a few of the possibilities of a thorough system 

 of marking birds, but in order to obtain results of real 

 scientific importance there are two essentials. Firstly, 

 to mark a large number of birds with such care that the 

 facts with regard to the identity of the birds, the numbers 

 on the rings and the dates and localities are indisputable ; 

 and, secondly, to recover such a proportion of the marked 



