44 BIRDS OF SOUTH DAKOTA 



FAMILY COLYMBID^E, GREBES; FAMILY GAVIID^, 



LOONS 



Among water birds Grebes and Loons are known as the 

 Divers. Six species of Grebes are found in North America, and 

 five of them have been taken in South Dakota. The other species, 

 known as the Mexican Grebe, is found in the extreme south- 

 western part of the United States. 



Of the five Loons inhabiting North America only one can 

 be called native to South Dakota, and this one is quite rare in the 

 State. 



All Grebes and Loons have legs set farther back on their 

 bodies than other water birds. They are therefore rapid and 

 graceful divers and able to swim long distances under water. 

 So quickly can they dive that when shot at three or four rods 

 away they disappear in the interval between the flash of the 

 gun and the striking of the shot. 



Neither of these species is edible. The Grebes are not 

 only harmless but useful, feeding on insects and larvae in or 

 about water. Loons feed on small fish and other aquatic forms. 

 Neither family is gregarious ; hence one sees only one or two in- 

 dividuals at a time. 



1. WESTERN GREBE (Aechmophorus occidentalis.) 



This Grebe is about twenty-six inches in length (from tip 

 of bill to end of tail), and is the largest of the Grebe family. 

 Body gray; throat and breast white; crown and back of neck 

 black in summer and gray in winter. A specimen in the Univer- 

 sity Museum, taken in Hamlin County by Mr. H. E. Lee, is in 

 winter plumage. This is a western species and a rare migrant 

 in South Dakota, although it formerly nested in Devil's Lake, 

 North Dakota. 



2. HOLBOELL'S GREBE (Colymbus holboelli.) 



Also a rare migrant in South Dakota and slightly smaller 

 than the Western Grebe. 



Back nearly black; belly white; crown black; cheeks and 

 throat white ; fore-neck light brown in adults and gray in young. 

 The specimen in the University Museum is a young one and 

 was taken in the Bellefourche Reservoir, Butte County. Winters 

 chiefly along the sea coasts. 



