64 BRITISH BIRDS. [voL. x1. 
organs are not mature, or that the birds, owing to lack of 
constitutional vigour, are backward and, being unable to 
breed, are not stimulated to assume the breeding dress. 
Then the question arises : do young birds breed in their first 
summer or not? In some waders, first summer birds 
apparently normally assume only a little of the breeding 
plumage, or moult into winter plumage, and it is doubtful 
whether they breed in their first year. Such birds are, as a 
rule, obtained in winter localities in the height of the breeding 
season. I have examined the following: Greater Yellow- 
shank :—¢ and Q, Chili, April and May in winter plumage, 
but for the underparts, new innermost secondaries and median 
coverts, as well as several other examples moulting in spring 
into winter plumage; in the Redshank, two from Orkney, — 
June, had acquired some breeding plumage and may have 
been breeding, while a male White Nile, 23/5/01, is in abraded 
winter plumage with a few summer feathers on the upper- 
parts ; other spring examples are in full moult into winter 
plumage. Of the Bar-tailed Godwit I have seen no first 
summer birds in breeding plumage; four shot in Scotland 
in May and June were in worn winter plumage with no trace 
of breeding plumage, two were not in moult, but one May and 
one June specimen were in full moult into winter plumage. 
The flocks of Oyster-catchers, Turnstones, Bar-tailed Godwits, 
and Curlews, which may be seen all summer through on certain 
parts of our coasts, are doubtless made up largely of these 
young non-breeding birds. A collection of such birds and 
a careful anatomical examination in each case would no 
doubt throw some light on the question as to whether first 
summer birds breed or not. The subject requires more 
investigation.* 
* Since writing the above, I have read Prof. Patten’s article on the 
“Migratory Movements of Certain Shore Birds as Observed on the 
Dublin Coast ”’ in the Naturalist (1909, page 83), in the course of which 
he gives particulars of flocks of Sanderlings, all apparently in nuptial 
plumage, being seen on the Dublin coast on several occasions during 
July; also flocks of Dunlin. He thinks it probable that these are 
immature birds and that Sanderling and Dunlin do not breed in their 
first year though assuming a plumage similar to the breeding plumage 
of the adult ; an anatomical examination of some Sanderling, obtained 
in August, confirmed his views. Prof. Patten also refers to Bar-tailed 
Godwits in winter plumage being seen throughout the summer on the 
Irish coast. He concludes that the mature waders migrate straight 
to their breeding grounds, while those that remain in flocks round our 
coasts, whether in breeding plumage or not, are immature birds 
which do not breed in their first year. There is little doubt, 1 think, 
that such is the case; though the flocks probably contain as well a 
certain percentage of non-breeding adults. 
