LESSER YELLOW-LEGS 343 



notes analogous with certain notes of the greater, these numbers are 

 omitted. 



Field marks. — There is no conspicuous character, except size, by 

 which the lesser yellow-legs can be distinguished in life from the 

 greater, unless one is expert enough to recognize the notes, which 

 are varied and variable in both species. From nearly all other 

 species it can be distinguished by its slender, shapely head and neck 

 and by its long, conspicuously yellow legs. Its light, almost white, 

 tail and rump contrast conspicuously with its uniformly dark back 

 and wings; adults in worn nuptial plumage appear almost black on 

 the upper parts; and there is no conspicuous white mark in the 

 wings. The lesser yellow-legs is most likely to be confused with the 

 long-legged stilt sandpiper in immature plumage; but the latter is 

 somewhat smaller and has olive-colored legs instead of yellow. 

 Adult stilt sandpipers, before they have entirely lost the barred 

 under parts, can be recognized by these marks and by other char- 

 acters described under that species. 



Fall. — Adult summer yellow-legs in worn nuptial plumage reach 

 New England in July, thus deserving the name. My earliest date 

 is July 11, but they are often abundant before the end of that month. 

 The young birds appear about a month later; the loose flocks are 

 made up of both ages in August; the adults usually depart before 

 the end of August, and few young birds are left after the middle 

 of September. 



Mr. Nichols says in his notes: 



It has frequently been remarked by old shore-bird gunners on Long Island 

 that the lesser yellowlegs and other species of shore birds in southward mi- 

 gration are abundant early in the season, and then after a period of compara- 

 tive scarcity become again more numerous. The explanation most commonly 

 advanced for this condition is two flights, first the old, then the young birds. 

 It is unquestionable that the first birds to come south are adults, but beyond 

 that fact this hypothesis will not hold. 



The fluctuation in numbers of the shore birds on Long Island during the fall 

 migration period may best be explained by supposing that the bulk of each 

 species has a more or less definite late-summer range to which it travels 

 from the breeding grounds and where, if conditions are favorable, it remains 

 until autumn. Before the main flight, birds of each species are mostly adults, 

 during it, mixed adults and young. To explain double abundance of most 

 species in southward migration by first the passage of adults, then that of 

 young, is pretty surely erroneous. Where such double abundance does occur 

 it is probably first birds passing through, second birds stopping to feed. 



There are not infrequent records of southbound lesser yellowlegs on Long 

 Island the end of June (June 24, 1922, my earliest at Mastic), and I have 

 seen a flock of 40 or 50 by July 10 ; July 31 is the earliest mention I chance 

 to find in my notes of a bird of the year. 



There is probably a considerable and regular migration at sea 

 for Capt. Savile G. Reid (1884) says that in Bermuda this is "the 



