COSTA'S HUMMINGBIRD 365 



these show some mixture of some of the above materials. The outside 

 diameter of the nests varies from I14 to nearly 2 inches, the average 

 being about li/^; the height varies from about 1^/4 to about II/2 

 inches. 



Mr. Dixon says in his notes sent to me : "The nest of the Costa is 

 very distinctive as to structure and material used, and I find this is 

 true with all of the hummingbirds, it being easier to tell the nests 

 apart than the female birds. The Costa uses dead weed leaves and 

 cobwebs in building the outside of the nest and soft plant down and 

 other soft materials for the lining. The general structure is of a 

 grayish tone and very distinctive in this respect." This grayish tone 

 of the nest helps to conceal it wdien it is built on a dead branch, a 

 dead yucca stalk, a gray-toned cactus, or, especially, in a sagebush 

 where the shreds of sage leaves with which it is decorated blend 

 perfectly with its surroundings. 



Griffing Bancroft (1930) says that in Baja California "they nest 

 in the immediate proximity of surface water, sometimes snuggled 

 into grapevine leaves, sometimes near the tips of fig branches, but 

 most often on the leaf stems of the date palm. The birds obviously 

 seek and usually obtain the protection of living foilage. The sites 

 selected average, in height above the ground, at least twice that of 

 northern breeders ; roughly eight feet against three." 



Mr. Woods (1927b) says : "x\t Azusa, California, the nests have been 

 found at heights ranging from two to nine feet, but most commonly 

 in the neighborhood of four feet. When a bush or small tree is se- 

 lected, as is frequently the case, the nest is almost invariably located 

 at a height of approximately one-half of the total height of the tree, 

 but near the outside rather than the center, and in a position from 

 which a reasonably clear outlook may be obtained. On this account 

 trees of dense, leafy growth, such as an orange tree in thrifty condi- 

 tion, are not favored. * * * If in a large tree, the nest is usually 

 on a small twig near the end of a projecting lower limb." 



Major Bendire (1895) says: "They are usually placed in low situa- 

 tions, from 1 to 6 feet from the ground, rarely higher, although Mr. 

 W. E. D. Scott records one taken on May 5, 1882, near Eiversicle, in 

 southern Arizona, from the extremity of a cottonwood branch 35 

 feet from the ground." 



Mr. Woods (1922) writes: 



On June 2, 1922, I found another Costa Hummingbird building a nest near 

 the end of a long horizontal limb of a good-sized avocado tree, at a height of 

 about five feet from the ground. Her method was first to alight in the nest, 

 then place the material under her and compact it by treading with the feet and 

 turning about. Material for the outside of the nest was placed while hovering 

 or while perched on a branch. On one occasion after leaving the nest the 

 bird flew up to a twig a few feet above, whereupon I was surprised to see 



