162 THE WILSON BULLETIN— December, 1921 



(Birds of Wisconsin, p. 66) give the following- informa- 

 tion : "• Formerly bred at Racine, and has been known to 

 remain at Lake Koshkonong throngh the snmmer. . . . We 

 have seen it in summer along the south shore of Lake 

 Superior, where it appeared to be nesting on the rocky 

 ledges." 



My OAvn field work has fortunateh^ included some in- 

 teresting experiences with the Duck Hawk in Wisconsin 

 and the following notes are offered : 



On May 20, 1911, an adult female, one addled egg and 

 one doTNTiy young, were collected about eight miles below 

 Prairie du Sac, on the Sauk county side of the Wisconsin 

 Kiver, by Mr, Bert Laws and the writer (see Auk, Jan. 

 1917, p. 61-65). Here for over a mile the sandstone bluff's, 

 forming the western boundarA- of Saidc Prairie, abut on the 

 river, the perpendicular, beautifully modeled rock faces fur- 

 nishing an ideal nesting environment for this species. Mr. 

 Laws states that they have nested on one or another of these 

 cliffs for over twent\^-fivo years to his knowledge. Early 

 tMs spring (1921) he noted a pair frequenting the most 

 easterly of these cliff's, known as Ferry Bluff, almost di- 

 rectly across the river from his home. On April loth, in 

 a pouring rain, we succeeded in locating their three eggs 

 on a ledge having a northeast exposure, overlooking a big 

 slough and miles of heavy river timber. The fenuile sat 

 very closely, only betraying the location of her treasures 

 when a stone thrown from below, landed on the ledge be- 

 side her. A well " white-washed " hole near tlie top of the 

 cliff, a short distance from the nesting ledge, was the reg- 

 ular roost of the male, and here he sat. framed by tlie cir- 

 cular opening, when we first approache<l. 



As may be seen by the accompanying photograph (Fig. 

 1), the ledge was perfectly protected from predatory ani- 

 mals, and we ourselves could only reach it with the aid of 

 ropes from above. Fortunately, however, we could see the 

 eggs from the top of a tall basswood tree that grew out 

 from a loam-covered rock mass well up the cliff. 



This pair were quite undemonstrative, though the male 

 would occasionally dart bj^ at tremendous speed while one 



