ooo Wetmore, Birds of Lake Burford, N. Mex. ljuly 



farther south into the mountains so that carrion from this source was no 

 longer available. 



33. Circus hudsonius (Linnaeus). Marsh Hawk. — On May 29, a 

 female was observed high over the lake and one was seen four miles above 

 El Vado on May 31. An adult female was noted at the lake again on 

 June 14. Apparently this species did not nest here. 



34. Accipiter velox (Wilson). Sharp-shinned Hawk. — This hawk 

 nested in small numbers in the pine-grown hills around the lake. A male 

 was seen playing in the air with a Cooper's Hawk on May 26. On May 27 

 one came darting through the sagebrush near the cabin and on June 2 

 one was seen in the gulch east of the lake. On the evening of June 6, 

 attracted by an uproar among the Yellow-headed Blackbirds, I found 

 a sharp-shin in the sagebrush just above the lake and shot it. This bird 

 was a breeding female and had both right and left ovaries present and 

 about equally developed, a common peculiarity among hawks of this 

 group. The right ovary had produced two mature ova as was shown 

 by the ruptured follicles and had another partly developed. The left 

 ovary had already produced one egg and had another ovum greatly en- 

 larged. The left oviduct only was developed. 



35. Accipiter cooperi (Bonaparte). Cooper's Hawk. — One was ob- 

 served on a forested hill east of the lake on May 26. 



36. Buteo borealis calurus Cassin. Western Red-tail. — One or 

 two pairs nested in the rocky hills bordering the canyon below the lake. 

 Individuals were seen at short intervals from May 26 to June 14. 



37. Aquila chrysaetos (Linnaeus). Golden Eagle. — Single birds 

 were seen three miles above El Vado on May 31 and June 12, and on 

 the latter date a pair of these eagles was observed near the Laguna de la 

 Puerta. Apparently they nest in the rock ledges bordering the canyon 

 below the lake. Limb bones of a Golden Eagle were picked up near the 

 East Bay. 



38. Falco mexicanus Schlegel. Prairie Falcon. — A pair of these 

 falcons had a nest containing young on an inaccessible ledge high up on 

 the sandstone cliffs bordering the canyon below the lake. The adults 

 frequently came across to hunt along the lake shore and harried the Yellow- 

 headed Blackbirds so mercilessly that these set up an outcry whenever 

 a bird of any size appeared on the skyline. Near the nest these falcons 

 frequently perched in dead trees as well as on the rock ledges. The nest 

 was easily located by watching and following the adults but was on a rock 

 shelf where it could not be reached without ropes. 



39. Falco peregrinus anatum Bonaparte. Duck Hawk. — A pair 

 of these swift-flying falcons had a nest in the canyon south of the lake 

 and the adults were observed hunting at the lake and in the open country 

 around it. The young left the nest about June 10 and were heard calling 

 from rocky points nearby for a day or two afterward. One was shot 

 from the boat on June 15 but was lost as it fell in a great expanse covered 

 with sagebrush above a shale bluff. 



