18 Birds of Colorado 



tips, a small subapical white spot generally on the inner web of the 

 second ; iris straw -yellow with red on the eyelid, bill greenish -yellow 

 with a yellow tip and a subapical black band, feet greenish-yellow. 

 Length 18-0; wing 14-25; tail 5-25; culmen 1-5; tarsus 2-0. 



In winter the head and neck are spotted with dusky. Young birds 

 are mottled with dusky above and below, especially on the wing-coverts ; 

 the primaries are black and there is no subapical spot on the first ; 

 the tail has a broad subterminal black band ; bill yellow on basal, 

 black on terminal half. 



Distribution. — Breeding chiefly in the interior of America, from 

 Colorado and Newfoimdland northwards to Hudson Bay and the 

 Barren Grounds. In winter, on the Atlantic and Pacific coasts south 

 to Cuba and Mexico. 



This is the only Gull which can be called at all common in Colorado. 

 It is fairly abundant on migration in spring and autumn, and 

 has been found breeding on the San Luis Lakes by Cooke. Migration 

 records are — Fort Lyon, March 23rd (Cooke), near Colorado Springs, 

 March 31st to May 1st (Aiken coll.), Barr Lake in smnmer and 

 winter, but not known to breed (Hersey & Rockwell), near Orchard 

 may be seen in March (Warren), Loveland, March 9 — 20th (Cooke), 

 all in the plains and foothills ; Twin Lake (Aiken coll.), South and 

 Middle Parks in spring (Carter), in the mountains ; and on the western 

 slopes — Grand River, near Grand Junction, June (Rockwell), Norwood 

 near Coventry, April, 1906 (Warren). 



Habits. — This Gull is found about lakes and rivers, 

 and has a singular habit of catching grasshoppers and 

 other insects in the air, noticed by both Allen and Goss. 

 Cooke found it breeding quite commonly at San Luis 

 Lakes (7,500 feet) June 18th, 1898, but gives no further 

 details. The nest, as with other Gulls, is placed on the 

 ground, usually on islands in lakes and ponds, and is 

 made chiefly of grasses ; the eggs, 2 to 3 in number, are 

 whitish to clay-coloured, rather evenly spotted with 

 chocolate ; they measure 2-30 x r65. 



Laughing Gull. Larus atricilla. 



A.O.U. Checklist no 58 — Colorado Records — Morrison 89, p. 147 ; 

 H. G. Smith 96, p 48 ; Cooke 97, p. 51. 



Description. — Adult in simamer — Head all round slaty-black, mantle 

 bluidh-groy, rest of the plumage, except the primary quills, wliite, a 



