BIRDS OF THE CAMBRIDGE REGION. 



45 



strong current in the opposite direction which brought salt water from the Mys- 

 tic River, sometimes in quantities sufficient to give the waters of the pond a 

 decidedly brackish taste. It was for this reason, I believe, that a flood-gate was 

 placed at the outlet about 1870. Three or four years later the brook was filled 

 in all the way from the pond to Concord Avenue, just below which it received, 

 for a time, the discharge of a city sewer. Its channel further to the northward, 

 also, was narrowed and straightened in many places. Thus by degrees, and 

 wholly through the intervention of man, has Alewife Brook become changed 

 from the broad, fair stream which the Cabots knew and loved so well to the 

 insignificant and hideous ditch, reeking with nameless filth, which now befouls the 

 greater part of the swampy region through which it flows. 



As a matter of course all these modifications in the surface conditions of 

 the Fresh Pond Swamps and Marshes, have been accompanied or closely fol- 

 lowed by equally marked changes in their characteristic bird life. This, how- 

 ever, is scarcely less rich and varied now than it was in the days of my youth. 

 It is true that a few birds once more or less common, as the Wood Duck, 

 the Night Heron, the Woodcock, and the Short-billed Marsh Wren, have nearly 

 or quite disappeared ; but to offset their loss the Black Duck and the Bittern, 

 which formerly occurred only during migration, are now regularly established 

 summer residents. There has also been a decided and indeed very considerable 

 local increase in the numbers of the Least Bitterns, Virginia and Carolina Rails, 

 Florida Gallinules, and Long-billed Marsh Wrens, — species which are known to 

 have inhabited the Fresh Pond Swamps for forty years or more. Most of these 

 changes — with others that might be mentioned — have evidently resulted chiefly 

 if not wholly from the recent increase and dispersion of the cattail flags, which 

 furnish food and shelter — as well as congenial nesting places — for very many 

 swamp-loving birds. 



The Pine Swamp and Pout Pond. 



At the southwestern extremity of the low, wet region just described, reach- 

 ing almost to Fresh Pond (at the head of Black's Nook) but separated from it 

 on the south by a high, wooded ridge, and also bounded on the east and west, as 

 well as partially on the north, by equally elevated but more open ground — lay 

 the Pine Swamp. Up to 1875, or a little later, it remained an essentially primi- 

 tive and strikingly beautiful bit of wilderness. Nearly half the swamp was 

 shaded by enormous white pines some of which had certainly stood for more 

 than a century, if not, as we liked to believe, since before the settlement of 

 Cambridge. There were also numbers of fine old oaks, beeches and yellow 



