1915^ J Bailey, Plum Island Night Herons. 427 



apparently, a deflection in their line of flight, many flocks passing 

 by altogether, well off shore. 



For twenty-five or thirty years past (if the information given 

 me by longshoremen and gunners long familiar with the region, 

 is correct) up to 1909, a colony of Black-crowned Night Herons 

 (Nycticorax nycticorax ncevius) have nested on the Island. This 

 colony I believe is one that about thirty years ago nested in a 

 hemlock swamp not far back from the Merrimac River in the town 

 of Amesbury. With the cutting off of the trees in this swamp and 

 its surroundings the birds were driven from their favorite and 

 probably long used breeding place here and resorted to the more 

 secluded site the Island afforded. My acquaintance with these 

 birds in this latter place began in 1904 when of a day's gunning on 

 the marshes I wandered back among the dunes and by chance 

 came upon the rookery. For the next five years my knowledge 

 of them was gained by several visits made at irregular intervals, to 

 the region, and for a description of these, I will, with a few correc- 

 tions and omissions of unimportant details, quote briefly from my 

 notes of those dates. 



August 12, 1904 — To the Plum Island marshes, gunning. The 

 weather cloudy, threatening rain: wind, moderate northeasterly. . . 

 The most interesting happening of the day occurred when after 

 tiring of gunning and tramping over the marshes, with indifferent 

 success, I wandered back among the sand dunes toward the sea- 

 shore near "Long Point" and in a deep, brushy, bowl-like depres- 

 sion between high dunes discovered a nesting colony of Black- 

 crowned Night Herons. As a conservative estimate of the birds here, 

 young and old, I placed the number at upward of 700. As there 

 was more or less of activity and commotion among them and a 

 continual passage of birds to and from the shore and at less regular 

 intervals from the marshes, it was rather difficult to form an 

 estimate. The number of nests served as a more reliable basis 

 to judge upon. A somewhat hasty count of these resulted in 157, 

 that I believed from appearances were, or had recently been, in use. 

 Granting that there were two adults for each nest, and an average 

 of three young (I believe the average would be higher than this), 

 the total would not be far above the figure named. 



I found a few young birds still in the nests but by far the larger 



