LIFE HISTORIES OE NORTH AMERICAN PETRELS AND PELICANS. 245 



venient nesting places, which are well patronized. During a short 

 cruise of less than a week we saw no less than five breeding colonies 

 of double-crested cormorants, ranging in size from 45 to 1,500 pairs. 

 The largest colony that I have ever seen was visited on June 18, 1913, 

 on a small triangular island near the northern end of the lake. A.s 

 we approached the island and anchored in the lea of it, preparing to 

 land, an imense cloud of the large black birds poured off the rocky 

 shores and began circling around us in a bewildering maze, and 

 mingled with them were a few of the great white pelicans, which 

 were also breeding on the island. It was an impressive sight. The 

 birds were much tamer than usual, for when we landed they were 

 still sitting on their nests on the farther side of the island behind a 

 Uttle, ridge, but they went scrambling off in haste and confusion as 

 soon as we were in plain sight. The cause of their tameness was soon 

 apparent for we were surprised to find that nearly all of the nests 

 contained young; this was rather remarkable, for none of the other 

 colonies contained any young at all and nearly all the eggs we had 

 collected were fresh or only slightly incubated. Perhaps this was 

 the oldest colony, for it was by far the largest, and had been occupied 

 by the earliest arrivals. In an average space 3 yards square I 

 counted 26 nests and by roughly measuring the whole occupied area 

 I estimated that there were between 1,500 and 2,000 nests in the colony. 

 The island was about 50 yards long by 40 yards wide, consisting of a 

 mass of boulders piled up quite high at one end with an accumulation 

 of bare soil in the center, probably the result of generations of guano 

 deposits. Except for a bare space in the center where the pelicans 

 were nesting, the whole island was covered with cormorants' nests 

 nearly down to the water's edge, even on and among the boulders. 

 The nests were made of sticks, dead weeds, canes, and flags, most of 

 which had been picked up as drift material along the shore; they 

 were lined with straws, grasses, and often with green leaves and 

 fresh twigs ; some were decorated or lined with gulls' feathers. One 

 large nest measured 14 inches in height and 18 by 22 inches in di- 

 ameter; most of the nests were much smaller than this and some of 

 them consisted of only a few sticks and straws. The nests and their 

 surroundings were far from atractive as the whole island was slimy 

 with excrement and reeking with dead fish ; the odor was almost un- 

 bearable. Some of the nests still held eggs but the great majority 

 held young of various ages, from naked, helpless, newly-hatched 

 chicks to well-developed, half-grown young, covered with jet black 

 down and squawking vigorously. 



Although I have never seen the double-crested cormorant nesting 

 in trees, as is the universal custom with its southern representative, the 

 observations of others indicate that it frequently does so in the south- 

 em portion of its range in the interior of the United States. Mr. 

 83969—22 17 



