Page:The Zoologist, 4th series, vol 6 (1902).djvu/410

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THE ZOOLOGIST.

weigh 4 lb., or even under, which was the weight of Mr. Popham's bird shot on the Yenesei. Mr. Chapman's bird at 2½ lb. was obviously in very poor condition.

Finally, it only remains now to discuss the probability of Anser gambeli crossing the Atlantic to the west coast of Ireland, or coming by some other route. I will at once and most emphatically express my opinion that there is nothing in the faintest degree unreasonable in suggesting that they can and do accomplish this journey easily and regularly. But we all know that these birds breed in the high north, and my own investigations in Iceland proved to me that White-fronted Geese only rest regularly there during the migratory period; which species I cannot say, but as likely to be gambeli as albifrons. Instead of the across Atlantic journey, it is more reasonable to assume that these birds come across Greenland—even if they do not breed there—to Iceland, and could then easily continue their journey downward, fringing the narrowest part of the Atlantic to Ireland. If Greenland and Iceland Falcons and so many other northern birds do it regularly, why not the powerful flying Wild Geese? If the Snow Goose (Chen hyperboreus) comes, why not A. gambeli? For my own part I should not doubt that they could easily cross even the broad part of the Atlantic.

The scepticism which has for so many years been indulged in with regard to American migrants visiting Great Britain must surely be utterly swept away now by the fact of so many American birds visiting our islands. The fanciful assisted passage theory is utterly inadequate to explain it, although it is perfectly certain that some birds do rest on vessels at sea, and travel with those vessels for a time, as instances have come under my own notice. But these occurrences are in no way sufficiently frequent to account for the great and increasing numbers of American birds which are coming to us—especially amongst the Waders. Even Yellow-billed Cuckoos and Carolina Crakes are just as genuine migrants as Snipe-billed Sandpipers, American Bitterns, Spotted Sandpipers, or American White-fronted Wild Geese.

There is one fact which all must admit, which is that of late years some birds are changing their lines of migration; further, that, in many instances, those birds breeding in the far north do