18 



KNOWLEDGE. 



[January 1, 1901. 



Conducted by Harey F. Witeerby, f.z.s., m.b.o.u. 



• 



Bird Migration in G-eeat Britain and Ireland. — 

 At the meeting of the British Associatiou iu 1806, it will 

 be remembered that the Bird Migration Committee 

 published a most important Digest of the Observations on 

 the Migrations of Birds at Lighthouses and Light-vessels 

 from 1880 to 1887.* This Digest was the work of Mr. 

 W. Eagle Clarke. Important and satisfactory as it was, 

 it was onlv considered as the foundation for future work. 

 Undaunted by the magnitude of his task, which cannot be 

 exaggerated, Mr. Clarke has not only continued his work 

 of systematically tabulating the 100,000 records of the 

 lighthouses, but he has added to this mass of facts many 

 more thousands of observations culled from the voluminous 

 literature published during the period covered by the 

 enquiry. Four vears of incessant toil since the publication 

 of the" Digest enabled Mr. Clarke to gather, sift, and 

 arrange, iu conjunction with the lighthouse re[.)orts, this 

 additional matter, so that the data being now as complete 

 as possible, " the time has arrived when, for the fii'st time 

 in the annals of British Ornithology, it is possible to write 

 an authoritative history of the migration of each British 

 bird." And not only is this possible, but we believe that 

 Mr. Clarke has so far advanced this most important and 

 valuable work that its publication will not now be long 

 delayed. As examples of his method of treating the 

 subject, Mr. Clarke furnished the British Association last 

 year with a summary of details of the various migratory 

 movements of two species — the Song Thrush and the 

 White Wagtail. The following brief abstract of one of 

 these may interest those who have not had an opportunity 

 of reading the original paper : — 



The MiGE-ATiONS of the Sono Thrush. — The Song 

 Thrush furnishes a most excellent example of the complex 

 nature of the phenomena of bird migration as observed in 

 Great Britain and Ireland. Its various movements cover a 

 period of nearly ten months of the year. Throughout 

 August and more especially in September and October 

 many Thrushes, which have bred here, move southward 

 to winter in warmer climes. At the end of September 

 and during the whole of October great numbers of 

 Thrushes from North- Western Europe invade the north- 

 east coast of Great Britain. Of these foreign-brel birds 

 many proceed south and finally quit our shores, the 

 majority to seek more southern lands, but others to winter 

 iu Ireland. Others, again, remain as winter visitors in 

 Englaud. This immigration of Thrushes from the Con- 

 tinent, unlike that of other species, ceases with the month 

 of October. In the winter (from October to February) we 

 have a difi'erent kind of migration. These movements are 



* For Summary of this Digest see Knowlkbob, November; 1896, 

 pp. 254—256. 



entirely due to outbursts of cold or bad weather. At such 

 times immense numbers of Thrushes, both residents and 

 intending winter visitors, rush to the coasts, along which 

 they proceed south and west. If the cold continues many 

 leave the country altogether, while others find refuge iu 

 Ireland. During February and March our own Thrushes, 

 which left us in the autumn to winter in the south, 

 gradually begin to return. Towards the end of March 

 the Thrushes which have wintered in the islands o& the 

 west of Scotland and Ireland take their departure for 

 Northern Europe. Throughout April those that have 

 wintered in the mainland depart as they came, via the 

 north-east coast of Englaud and the east of Scotland. 

 Merged somewhat with this latter movement are the 

 travellers which pass during April and occasionally in 

 May along our eastern seaboard on their way from the 

 south to the north of Europe. 



These are the main points in the complicated migratory 

 movements of the Song Thrush in Great Britain. All 

 ornithologists will heartily agree with the Migration 

 Committee that "A great debt of gratitude is due to Mr. 

 Clarke for the courage and perseverance which he has 

 shown in grappling with the enormous mass of statistics 

 necessary 1:0 att'ord the results so lucidly and concisely 

 summed up by him." 



Baird's Sandpiper in Sussex. — A New Bird to the 

 British List. — At the meeting of the British Ornitho- 

 logists' Club, held on November 2Ist, 190O, Mr. Ernst 

 Hartert exhibited a youug female specimen of Baird's 

 Sandpiper {Heteropyqia hairdi). The bird was shot at 

 Eye Harbour, Sussex, on October llth, by Mr. M. J. 

 NicoU. Mr. Nicoll wrote that the flight was like that of 

 the Common Sandpiper for the first few yards, then the 

 bird rose straight in the air for a considerable height, and 

 then dropped suddenly towards the ground. It did this 

 every time it was flushed. Its cry was a shrill twitter, 

 difierent from that of any British species. The bill and 

 legs were jet black. Baird's Sandpiper is au American 

 species. 



British Form of the Willow Tit {Parus salicarius). 

 — In Knowledge for April, 1898, p. 81, we drew attention 

 to this bird, which Mr. Hartert introduced to the British 

 list from specimens obtained at Finchley. At the Novem- 

 ber meeting of the Biitish Ornithologists' Club, Mr. 

 Hartert announced that he had found a specimen in the 

 collection of Mr. Ticehurst, from St. Leonards, and had 

 recently received fresh skins from Mr. Ruskiu Butterfield, 

 from Hastings. The bird would no doubt be detected in 

 other localities, when British ornithologists were able to 

 distinguish the Willow Tit, with its dull head, from the 

 ordinary Marsh Tit with its glossy crown. Ornithologists 

 will do well to carefully observe Marsh Tits, in the hope 

 of distinguishing the Willow Tit, and thus obtain more 

 evidence regarding the bird in Great Britain. There is a 

 little difficulty about the name of the bird. For those 

 who accept trinominals and unite all the dull-headed 

 forms of the Grey Tits, the Continental Willow Tit would 

 be PariijS montaniig salicarius, and the British form Parus 

 montanns Kleinschmidti ; otherwise the British AVillow 

 Tit might be called Parus Kleinschmidti , since it differs 

 from the Continental form by being slightly smaller and 

 more richly coloured. Those who do not recognize the 

 slight differences of the Continental and British forms of 

 the Tits as worthy of specific rank should call the bird 

 Parus salicarius, and in taking Mr. Saunders' Manual as 

 the standard book on British birds, and following his 

 decisions regarding the Long-tailed Tit and the Coal Tit, 

 we are inclined to call the Willow Tit simply Parus 

 mlicarius. 



