THE RECENT REMARKABLE VISITATION OF CROSSBILLS 215 



THE RECENT REMARKABLE VISITATION 



OF CROSSBILLS. 



By Wm. Eagle Clarke, F.L.S., F.R.S.E. 



The summer of 1909 will be remembered by ornithologists 

 for its remarkable visitation of Crossbills {Loxia awvirostrd). 

 During late June, all July and August, these birds were 

 widely spread over Great Britain, but seem to have come 

 most under notice at the Northern Islands of Scotland, 

 where forests and other cover are non-existent. 



These early summer migrations are not very unusual on 

 the part of the Common Crossbill. It has long been known, 

 for some reason not as yet determined, that at the close of 

 the breeding season, which is an early one, these birds and 

 their young quit their continental forest homes to appear 

 among us, and occur in the most out-of-the-way and, for 

 their food requirements, unsuitable places. The irruption, 

 however, of 1909 is remarkable for the number of the visitors, 

 and the wideness of the area covered. 



They were first detected on Fair Isle, where Stewart 

 Stout, our bird-watcher, saw the first on the 23 rd of June. 

 Their numbers afterwards increased, as if the birds had 

 come to the island in a series of waves, and as many as 

 300 were seen some days. They remained on the island 

 throughout July, but their numbers fell off towards the end 

 of that month. They were observed there, however, during 

 the whole of August in small parties. 



In Unst, the northern island of the Shetland group, on 

 the 27th of June, an adult male came under the notice of 

 Dr. Edmondston-Saxby, who, in reporting the occurrence, 

 remarked that he had only once previously seen this bird in 

 summer. 



In the neighbourhood of Lerwick they were first observed 

 on the following day, and from that day onwards until the 

 I 3th of August, the day on which he wrote me last, Mr. J. S. 

 TuUoch tells me that he saw small parties, but never more 

 than a dozen strong. He, however, heard of as many as 

 thirty having been seen in a flock ; and he had Crossbills, in 



