BIRDS OF COLORADO. * 5 1 



would be supposed then that it would be not uncommon in 

 Colorado and it may yet be found rarely in the western part of 

 the State, or even breeding, but at present the only record for 

 Colorado is the one taken by Prof. Wm. Osburn, at Loveland, 

 May 7, 1890. 



54. Larus delawarensis. Ring-billed Gull. 



Summer resident, rare; in migration, common. The only 

 gull that is commonly found throughout Colorado. Many are 

 seen in the spring migration and they are very common in 

 autumn on all bodies of water below 9,000 feet. They migrate 

 early, appearing in southern Colorado by the middle of March. 

 F. M. Drew records it as breeding at 6,000 feet. (Auk, II. 

 1885, II.) 



58. Larus atricilla. Laughing Gull. 



A gull of the South Atlantic and Gulf States accidental 

 once in Colorado. One was shot at Sloan's Lake near Denver 

 in December, 1889. (H. G. Smith, Nidologist, III. 1896, 48.) 



59. Larus franklinii. Franklin's Gull. 



Migratory; rare. Has been taken by Wm. G. Smith, at 

 Loveland, and A. W. Anthony saw a freshly mounted specimen 

 said to have been taken near Denver. 



60. Larus Philadelphia. Bonaparte's Gull. 

 Migratory; rare. Eight specimens have been recorded, 



and every one has been taken along the edge of the plains from 

 Colorado Springs to Fort Collins. Nearly all were captured in 

 the fall, when it is reported as not uncommon in some localities. 



62. Xema sabinii. Sabine's Gull. 



Winter visitant; rare. Breeds far north and comes south 

 for the winter. Five occurrences have been recorded, all in the 

 fall and early winter from October to December. They were 

 noted at Denver, Boulder, Loveland and Fort Collins. 



69. Sterna forsteri. Forster's Tern. 



Summer resident, rare; in migration, not uncommon. 

 According to Mr. Ridgway a few breed in the State (Bull. Essex 

 Institute, V. Nov. 1873, 174), but most of them are merely 

 migrants. They are almost as common in the spring as in the 

 fall. They reach northern Colorado the last of April and early 

 in May. 



71. Sterna paradissa. Arctic Tern. 



Migratory; very rare. But two instances are on record. 

 Prof. Wm. Osburn has an adult male that was shot at Loveland, 



