58 NORTH AMERICAN FAUNA 61, FISH AND WILDLIFE SERVICE 



On May 16, 1936, while anchored at Unga, in the Shumagin 

 Islands, we discovered a good-sized colony of red-faced cor- 

 morants on the precipitous cliffs of a rocky point. There were 

 about 300 birds beginning to nest. Some of them were carrying 

 nesting material; many had no nest at all. In our experience, 

 this is the easternmost colony of this species. 



In 1925, I found a colony on Amak Island, a small conelike 

 island off the west end of Alaska Peninsula in Bering Sea. It 

 was estimated that there were between 4,000 and 5,000 birds 

 nesting on the high cliffs — by far the largest colony known south 

 of the Pribilofs. When visited again in 1936, these birds were 

 still nesting on the same cliffs, many of them carrying nesting 

 material (on May 31). On May 22, 1928, Jaques (1930) ob- 

 served this species near Port Moller. 



Bogoslof Island is also occupied by .ed-faced cormorants, 

 mostly in the form of individuals scattered among a large number 

 of murres. 



While most of the Aleutian colonies of the red-faced cormorants 

 are very small, there are a few sizable concentrations. On Adokt 

 Island, one of the Baby Islands group in Unimak Pass, we esti- 

 mated 500 nests. There were also large concentrations on certain 

 islets in the Bay of Islands of Adak Island. But in many instances 

 there were small groups, sometimes six or less. 



Following are the islands, east to west, on which the red- 

 faced cormorant was found nesting: Unga (Shumagins), Amak, 

 Adokt and Excelsior of the Baby Islands group, Egg (probably), 

 Poa, Tangik, Bogoslof, Ananiuliak near Umnak (not certain), 

 Uliaga, Kagamil, Carlisle, Herbert, Yunaska, Chagulak, Amukta, 

 Seguam, Ulak, Kasatochi, Igitkin (probably), Adak, Gareloi, 

 West Unalga, Semisopochnoi, Amchitka, Little Sitkin, Davidof, 

 Kwhostof, Kiska, Agattu, Semichi, and Attu. 



These birds were identified at other islands, though nests were 

 not actually observed. This gives the red-faced cormorant a 

 fairly uniform distribution as a nesting bird from Unga and 

 Amak Islands, and Port Moller, all the way to Attu, and they 

 are known to nest still farther west, in the Commander Islands. 

 The red-faced cormorant also winters in the Aleutian waters. 



Mortality Factors 



Birds which prey on the cormorants are the bald eagle, pere- 

 grine falcon, and glaucous-winged gull. In a study of the food 

 habits of the bald eagle in the Aleutians it was found that 

 cormorants had been taken for food frequently; however, the 

 species of cormorants was not determined. It seemed likely 



