154 BULLETIN 113, UNITED STATES NATIONAL MUSEUM. 



Spring migration. — Adults return to their breeding grounds from 

 both northern and southern winter ranges in March. 



Fall migration. — Northward movement begins in May, reaching 

 southern California about June 1 ; Monterey, June and July ; Faral- 

 lones, May 20 to June 3 ; British Columbia, Vancouver Island, June 

 28. Southward retirement again begins in August, or even July, 

 but last birds do not leave Puget Sound until October, and few 

 remain in Washington until November. Bulk of the flight passes 

 Monterey in November, but a few birds winter there. 



Egg dates. — Mexico, west coast : Fifteen records, April 8 to June 

 17 ; fourteen records, April 8 to 11. 



LABUS ATRICILLA Linnaeus. 

 LAUGHING GULL. 



HABITS. 



High above the gleaming sands of Muskeget Island, amid the 

 whirling maze of hovering terns that swarm up into the blue ether 

 until the uppermost are nearly lost to vision, may be seen some 

 larger birds, conspicuous by their size, by their black heads and 

 black-tipped wings, soaring at ease among their lesser companions. 

 In the ceaseless din of strident cries may be heard occasionally the 

 hoarse notes of this larger bird — notes which, from their peculiar 

 character, give the bird the fitting name of laughing gull. Although 

 larger and stronger than the terns the laughing gulls are much 

 shyer and less aggressive on their breeding grounds; the observer 

 must remain concealed for some time under a well-made blind before 

 they will return to their nests in his vicinity. 



The Muskeget Island colony is certainly the largest breeding 

 colony of laughing gulls north of Virginia; it is therefore worthy 

 of description, as typical of the numerous colonies which formerly 

 existed all along the coast from Maine southward. Much has been 

 written about this interesting island, and I have given a brief 

 description of it under the head of the common tern. These gulls 

 formerly bred here abundantly, but constant persecution reduced 

 their numbers until they became very scarce about 1880, and would 

 have been extirpated except for the protection afforded them by the 

 passage of suitable laws and by the personal efforts of Mr. George 

 H. Mackay in seeing that the laws were enforced. They increased 

 slowly during the next 10 years, but after 1890 their increase was 

 more encouraging. In 1894 the colony nearly doubled in numbers 

 and it continued to flourish, increasing a little each year, until, at the 

 time of my last visit (in 1919) it consisted of several thousand pairs. 



