266 BULLETIN 113, UNITED STATES NATIONAL MUSEUM. 



istics as the one first described, and upon the higher portions the bii'ds nest 

 even more commonly, for, as against the 20 pairs or so nesting on the first is- 

 land, some 30 or 40 pairs occupied the latter island both seasons when it was 

 visited by the writer. From the proximity of native villages, and owing to the 

 pei'secution received at the hands of Turner and myself, the birds on these is- 

 lands were very shy, and it was no easy task to secure specimens. 



Nesting. — While passing through St. Michael on July 8, 1914, 

 my assistant, Mr. Hersey, secured two specimens of Aleutian terns, 

 and again on July 17, 1915, he succeeded in collecting a small series 

 of these interesting birds near the island referred to above. I had 

 sent him there again in 1915 to spend the whole summer in the vicin- 

 ity of St. Michael. His several visits to the island at the mouth of 

 the canal resulted in his securing several sets of eggs, mostly sets of 

 two, taken on June 23 and 28 and July 3. His notes state : 



The Island where the Aleutian terns breed rises rather abruptly from the 

 water to a height of about 25 feet and then spreads out broad and fairly level. 

 At one end are several small ponds, and here it is lower than at other places. 

 The higher parts are covered with a mat of dry grass of last year's growth, 

 through which the new green blades are now appearing. In this matted grass 

 the terns are now nesting, not in a compact colony, but scattered about in single 

 pairs. Although apparently nesting anywhere over this space, the nests are 

 in reality placed rather near the edge of the island, and in most cases the sitting 

 bird could look out over the water. I found no nests in the center of the island. 

 Among this tangle of dry grass are interspersed patches of a soft gray moss 

 which grows close to the ground. These patches vary from 1 or 2 feet in diam- 

 eter to several yards in size. In these patches of moss the nests are generally 

 made, the small ones being selected as the near-by grass affords some con- 

 cealment. None were found among the larger patches. One nest was found 

 on a mound of rotten wood, where a log of driftwood had decayed. The nest 

 is a depression in the moss 3 or 4 inches across and about IJ inches deep, and 

 is unlined. Two eggs appear to complete the set. 



While walking over the island the birds circled high overhead, and nothing 

 in their actions disclosed the location of any of their nests. They seldom 

 came very near even when a nest was found, but one pair of birds darted down 

 close to my head as I neared their nest. When I first landed on the island 

 where the terns were nesting the birds began to fly up out of the grass, and by 

 marking the spot from which they rose a nest could generally be found. 

 Although but slightly concealed I found the nest exceedingly hard to find, and 

 it took an average of an hour to locate each one. 



Eggs. — Mr. Hersey's experience would seem to indicate that two 

 eggs constitute the normal set; probably three eggs are rarely laid, 

 and occasionally only one. Several sets of three eggs each, collected 

 on Stuart Island by Capt. H. H. Bodfish, are probably eggs of the 

 Arctic tern. Some of these that I have seen do not show any of the 

 well-marked characteristics of Aleutian tern's eggs. Moreover, Mr. 

 Herse}', who spent considerable time on Stuart Island, says that it is 

 not at all suited for the breeding requirements of the Aleutian tern, 

 and that none breed there, though the Arctic tern does breed there. 



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