32 BULLETIN 196, UNITED STATES NATIONAL MUSEUM 



date in my possession at which any Robins have been actually found in a roost 

 is Oct 20, 1889, when Mr. Faxon noticed a few still lingering at Beaver Brook, 

 but my notes record that on Nov. 6, 1888, I saw a succession of flocks flying, at 

 sunset, into these Beaver Brook woods which, at the time, were "leafless"! About 

 200 Robins were seen on this occasion. They were in unusually large flocks, 

 one, which passed me closely, containing fully 100 birds. If, as seems probable, 

 they were migrants from further north it is interesting that they should have 

 found their way to this roost; but perhaps enough local birds were with or near 

 them to serve as guides. Mr. Faxon believes that our roosts receive some acces- 

 sion- from the north as early as September. 



Continuing, Mr. Brewster adds: "Most of the roosts which I have 

 visited are resorted to by other birds besides Kobins." Among these 

 he mentions bronzed grackles, cowbirds, red-winged blackbirds, 

 kingbirds, Baltimore orioles, cedar waxwings, and brown thrashers. 



Brewster (1906) also gives an interesting account of the behavior 

 of the robins at a roost in his dooryard in the city of Cambridge. He 

 says: 



Late in June, 1902, they began assembling every evening — to my infinite sur- 

 prise — in some ancient lilacs which form a dense and rather extensive thicket 

 in the garden immediately behind our house. At first there were not more than 

 twenty or thirty birds, but their numbers rapidly increased until by the close 

 of summer we often counted as many as four or five hundred. * * * During 

 the whole of May the roost was frequented nightly by fifty or more birds, all 

 apparently old males. By the middle of June these were joined by the first 

 broods of young, and a month or so later by the old females with their second 

 broods. Thus the number of Robins steadily increased until early in August, 

 when it probably reached its maximum and when we sometimes noted upwards 

 of seven hundred birds in the course of a single evening. The frequent presence 

 of members of my family on the back piazza (which is only a few yards from the 

 lilacs) when the evening flight was coming in, gave the Robins some concern at 

 first, but they soon became perfectly reconciled to it. * * * 



As the piazza faces a little opening about which the lilacs are grouped on the 

 remaining three sides, it commands an unobstructed view of the roost and affords 

 rare facilities for watching the birds at close range. I have been interested to 

 learn that a sound resembling the pattering of hail, which is heard when they 

 are fluttering among the foliage and which I had formerly supposed to be caused 

 by their wings striking the leaves, is really made, at least in part, by their bills. 



When two or more of them are contesting for possession of the same perch they 

 first threaten one another with wide-opened beaks and then bring their mandibles 

 rapidly and forcibly together, thereby producing the sound above described. 

 After they have quite ceased their calling and fluttering one may pass — even in 

 bright moonlight — within a yard or two of branches where they are roosting by 

 dozens without disturbing them. They invariably begin to leave the roost at 

 daybreak, usually departing singly or in small parties, and scattering in every 

 direction. When the exodus is performed in this manner, it often continues until 

 sunrise. On several occasions, however, I have seen practically the entire body 

 of birds leave simultaneously in the morning twilight, in one immense flock, with 

 a prodigious whirring of wings. The evening flights vary similarly in character 

 but to a less degree. Ordinarily the incoming birds are arriving more or less 

 continuously for half an hour or more, but occasionally the majority of them 



