iSyo.J Brewster on Robin Roosts. 'iGl 



ciduous trees as maples, oaks, chestnuts, and birches, sometimes 

 mixed with white pines. I have never known Robins actually to 

 spend the night, however, in the latter, or indeed in any species of 

 evergreen, except at Falmouth, Mass., where there has been a 

 small gathering, these past two seasons, in a white cedar swamp. 

 The trees in the roost may be tall and old with spreading tops, or 

 crowded saplings only twenty to thirty feet in height, but it is 

 essential that they furnish a dense canopy of foliage of sufficient 

 extent to accomodate the birds which assemble there. As a rule, 

 the woods are remote from buildings, and surrounded by open 

 fields or meadows, but the latter may be hemmed in closely 

 by houses, as is the case with a roost which at present 

 exists in the very heart of Cambridge. A roost once estab- 

 lished is resorted to nightly, not only during an entire season, 

 but for many successive seasons. Nevertheless it is sometimes 

 abandoned either with or without obvious cause, as the following 

 account of the movements of the Cambridge Robins during the past 

 twenty odd years will show. 



I first found them roosting in the summer of 1867 in a tract of 

 some ten or twelve acres of swampy woods situated about two 

 hundred yards to the north and east of Fresh Pond and known to 

 Cambridge collectors as the 'Maple Swamp.' The birds which 

 came to this swamp approached it chiefly from the direction of 

 Cambridge, the main body of the flight entering on the south and 

 east sides. Probably it accommodated all the Robins which at 

 the time bred in or very near Cambridge, for from every part of 

 that city the flights led straight towards it. It also received some 

 contributions from the country to the north and west, but these 

 were comparatively trifling. 



Either in 1S73 or 1S74 the Cambridge Robins deserted the 

 Maple Swamp and found another roost in a similar piece of 

 swampy woods on the opposite (northern) side of the Fresh 

 Pond marshes, near the north bank of Little River not far 

 from Spy Pond, and just within the borders of Arlington. The 

 cause of this desertion was somewhat obscure, for the place 

 which they left had undergone no sudden or marked alteration, 

 nor had they been molested there to any considerable extent, 

 while the change added nearly a mile to the length of their morn- 

 ing and evening flights, the course of which lay directly over the 

 former roost where the passing birds would sometimes alight for 



