iij Mackay on the Breeding Habits of La r us atricilla. T o"^ 



On May 14, 1S93, two birds were seen, and about a dozen more 

 heard; they were very High up. These were the first arrivals 

 noted this season on Muskeget Island. On May 17 a strong 

 breeze from the south was blowing and about twelve birds were 

 seen flying low down over Muskeget. On May 2S about thirty 

 were noted ; they were mixed in and flying with the Wilson 

 Terns {Sterna hirundo) and were hovering close to the ground. 

 On June 7, 1S93, four nests were discovered near the centre of 

 the island, being the first found this season. One of these con- 

 tained two eggs, the others being empty. The most of the birds, 

 however, seemed to be collecting on the north side of the island 

 with the evident intention of breeding in that locality. 



They usually appear about these islands during the month of 

 Mav, and depart in October. The first birds were noted in 1S92 

 on May 10 (two pairs) at the north pond, Tuckernuck. In 1S93 

 they were first noted on May 7 near the same place (four pairs) . 

 They prepare their nests about the first of June ; these are regu- 

 larly constructed and are composed of interwoven dried sea grass 

 (Zostera marina), grass, and stubs of beach grass (Ammophila 

 arundinacea) . The inside of the nest is about the size of an 

 ordinary saucer, and it is usually placed at the foot of a tall bunch 

 of crass, under a bush, or in beach peas {jLathyrus maritimus). 

 Often it is well concealed ; at other times it is exposed to view 

 and easily seen at a distance of a few feet. I have also seen it 

 placed on top of a bunch of old beach grass stubs surrounded by 

 beach peas, which is a favorite location. This was noticeably 

 the case in 1S93, when on June 20 I found eight nests, and 

 one on July 3 with two eggs, in such position that all were 

 within forty yards of each other. They nest in colonies in this 

 locality, and when one nest is discovered it is nearly certain 

 others may be found near by. 



In the summer of 1S92 these birds nested on Muskeget between 

 the slight headland (one of the old shore lines) and the shore, 

 on the north side of the island and within two hundred and fiftv 

 yards of the ocean and about twenty-five yards from a small fresh 

 water pond. The nests were placed on the slope of the headland 

 towards the shore, where there was an abundance of rank grass 

 about two feet and a half high. In 1S91 a few pairs built in a 

 salt marsh or meadow on the south side of the island, the nests 



