278 



SCIENCE-GOSSIP. 



such a systematic tabulation of at least one 

 hundred thousand records, culled from several 

 thousands of forms filled in b\- the light-keepers, 

 in each of which species were numerous and the 

 dates wide ranging, proved to be both a long and 

 laborious task. 



' ' The results now presented are, for the first time, 

 based upon the examination of the 'dhole of the 

 information communicated to the Committee for 

 all the coasts : a most necessary condition, for from 

 such a complete and comprehensive examination 

 alone could it be at all possible to obtain results 

 worthy of the inquiry, and an accurate knowledge 

 of the nature of the various phenomena associated 

 with the migration of British and Irish birds. 

 Indeed, it is now in our pov\-er to declare that it is 

 quite impossible at certain seasons to distinguish 

 between the wideh' different immigraton,- and 

 emigraton,- movements without due examination 

 and consideration of the whole of the observations, 

 a fact the non-realization of which has been fruitful 

 of much misconception and of manj- misleading 

 statements in the past. 



"It is manifestly impossible to conduct an in- 

 quiry- into the migration of birds over the entire 

 British area, or even of the smallest section of it, 

 rmder other than imperfect conditions ; a hundred 

 circumstances are against such a desirable consum- 

 mation. Even if a part}- of trained ornithologists 

 were placed at each station, it w-ould fail to secure 

 anything like perfect results. . . . 



" The object of the inquiry was to obtain full 

 and trustworthy information in connection %vith the 

 migrator}' movements of birds as obser\-ed on our 

 coasts, and not to solve problems connected with 

 the causes of the phenomena, the evolution of the 

 migrator}- instinct, or other purely theoretical 

 aspects of the general subject. 



' ' As regards the importance of this investigation, 

 it must be borne in mind that the observers were 

 most favourably stationed for witnessing migration 

 in its various phases, and that such a voluminous 

 and complete set of obser\-ations has never been 

 amassed at any pre\ious period in the history of 

 the study of bird-migration. Its special nature 

 can only be fully appreciated when it is realized 

 that in order to study the phenomena of bird- 

 migration in the British Islands it is necessary 

 that the data upon which any deductions may be 

 satisfactorily or safely founded should be based 

 upon observations taken synchronously at stations 

 encircling the entire coasts. This cardinal and 

 most important condition has been attempted 

 and accomplished for the first time, either in this 

 or any other country, through the labours of the 

 Committee. 



" The meteorological aspect of the subject has 

 received very careful attention, and %rith interesting 

 and important results. In connection with this 

 portion of the v.-ork, the ' Daily Weather Reports ' 

 issued by the Meteorological Office have been 

 consulted and correlated with the data relating to 

 the migratory movements for each year of the 

 inquir}-. 



" Finally, I may state that the results now 

 communicated are based absolutely upon the 

 records obtained by the Committee ; and also 

 that I have approached the subject with an open 

 mind and %\-ithout preconcei%-ed ideas. I have 

 considered this not the place for theory, but for the 

 establishment of facts, and for deductions drawn 

 from a direct study of the observations placed in 

 my hands. 



"The migration of birds as obser^-ed in the 



British Islands is a very complex phenomenon ; 

 more so, perhaps, than in any other region of the 

 globe. This is readily accounted for. 



First, the geographical position of the British 

 Islands is eminently favourable. Placed as our 

 Isles are, between South-western Europe and the 

 Scandinavian peninsula, Iceland and Greenland, 

 they lie directly in the course of the legions of 

 migratory birds which annually make a double 

 journey between their northern summer and their 

 southern winter quarters. For these birds of 

 passage our shores form not only a main and much- 

 accustomed highv.ay, but afford convenient resting- 

 quarters. 



" Secondly, our islands have avast bird-population 

 of their own, and the majority of these birds 

 belong to purely migratory species. Some of them 

 are either summer visitors from the southern 

 regions or winter visitors from Continental Europe, 

 Iceland, etc. 



" Thirdly, many individuals of species which 

 are sedentarj' in our islands are strictly migra- 

 tor}-. This is especially the case in the more 

 northern and elevated portions of the British 

 area : hence these species are said to be ' partial 

 migrants." 



" Finally, our remarkably variable climate is a 

 constant element of disturbance, causing much 

 migration within the British area itself and in- 

 termigration with the islands off our v.-estern 

 coasts, especially with Ireland. This occurs during 

 the winter months, and hence these migrations 

 v.ill be alluded to in this report as ' winter 

 movements.' 



"The above important considerations and 

 influences result not only in much migration of a 

 varied nature being %ritnessed on our shores, but 

 often, thro'dgh a combination of meteorological 

 conditions, in more than one movement being 

 observed in progress simultaneously, adding much 

 further intricacy to an already complicated series 

 of phenomena. 



" Ha\T.ng thus shortly described the British 

 Islands as a highway for and as a source of migra- 

 tion, ha-\-ing mentioned the nature of the various 

 movements observed on our coasts, and ha%-ing 

 alluded to the influence exerted by climatic 

 conditions upon the bird-population of our area, I 

 may now proceed to discuss the main results 

 obtained through the inquin,- under the following 

 sections : (i) Geographical, (2) Seasonal and (3) 

 ^leteorological." 



ITo be continued.) 



Marine Natural History. — Like Dr. Tatham 

 {ante p. 255), I notice with regret the absence from 

 Science-Gossip of notes on Marine Biology. Some 

 years ago, as opportunity occurred, I did a little 

 work in it myself, and always found it most fascina- 

 ting and productive of fresh objects for examination. 

 I should be glad, now my facilities are lessened, to 

 know what others may have to relate of their ex- 

 periences. Surely there must be many readers of 

 SciENCE-GossiP dwelling at the sea-side who could 

 gratify their less fortunate town brethren with an 

 account of their finds. Even short notes are 

 interesting and useful, and are certain to be 

 welcomed by the Editor, for has he not frequently 

 told us that it is just this section of his paper — 

 which ought to be so easily and fully supplied — 

 that he has difficulty in filling. — Jas. Burton, 9, 

 Agamemnon Road, West Hampstead. 



