472 GAME BIBDS OF CALIFOENIA 



distance with such rapid foot inovenient and even carriage of the body- 

 that it seems to fairly glide over the surface of the sand ; then it 

 stops abruptly to dab slantingly into the wet sand for morsels of food. 

 Ground worked over in this manner shows a multitude of bill marks. 

 The movements of the birds are, as compared with those of sandpipers, 

 more deliberate,; now and then an individual momentarily dips its 

 fore parts, a mannerism shared among several of the plovers. Ordi- 

 narily when the birds are scattered out over a feeding ground they 

 are oblivious to one another 's presence ; but, should danger threaten, 

 the signal of one sets all on guard. As they take wing the members 

 of a flock bunch quickly together and fly off, rapidly, in close forma- 

 tion, with numerous utterances of their clear, two-syllabled call-note. 

 The Semipalmated Plover differs from the Killdeer in being much 

 quieter, more gregarious, and in showing a decided preference for 

 maritime forage grounds. 



Unlike its near relatives, the Killdeer and Snowy Plover, the Semi- 

 palmated Plover has selected the far north for its breeding ground. 

 Authentic instances of nesting involve the region lying from the Gulf 

 of St. Lawrence northwest to Fort Yukon, Alaska, and north to Mel- 

 ville Island. In this territory, eggs have been taken from June 2 

 (1862) to June 21 (1875) (Cooke, 1910, p. 90), while eggs just 

 hatched were secured July 6, 1899 (Bishop, 1900, p. 70). The nest 

 seems to be usually located on sandy or pebbly shores, or in short 

 grass, and in any instance but a short distance from water. It is often 

 a mere shallow depression in the surface without lining of any sort ; 

 at other times a sparse layer of grasses or leaves is provided for the 

 eggs to rest upon. The eggs are usually four in number and measure 

 in inches, 1.20 to 1.40 by 0.90 to 1.00. The ground color is light drab 

 or buff, with rather sparse and scattered superficial markings of black- 

 ish brown, and deeper ones of purplish slate (Baird, Brewer and 

 Ridgway, 1884, I, p. 157 ; Macoun and Macoun, 1909, p. 207 ; Davie, 

 1900, p. 155). The Semipalmated Plover seems to be less demonstra- 

 tive than many others of its kind, although some attention may be 

 paid to an intruder when he first approaches the nest. MacFarlane 

 (1891, p. 430) says of the birds seen in Arctic America: "When 

 closely approached, the female usually glided from her nest and ran 

 a short distance before flying, occasionally drooping her wings and 

 pretending lameness." 



Bishop (1900, p. 70) records the finding of a pipped egg at Lake 

 Marsh, in southern Yukon Territory, July 2, 1899. He says: "I 

 removed the young bird from the shell, and within half an hour the 

 down was almost dry, the eyes were open, and it could hop about on 

 its 'knees'." Bare areas on the skin of the under side of the body in 

 both parent birds showed tliat llic duties of incubation are shared 

 by the two sexes. 



