The U.S. Geological Survey, Colorado Plateau Field Station, and EMA completed an avian survey of the upper reaches of Fossil Creek in 2004. Released in October 2005, the final report was prepared by Chris Calvo, Matthew Johnson, and Jennifer Holmes of Northern Arizona University and entitled “Common Black-Hawk and Yellow-billed Cuckoo distribution and abundance in the upper reach of Fossil Creek, AZ, 2005.” The Yellow-billed Cuckoo and the Common Black Hawk were selected as part of the Fossil Creek Faunal Monitoring Program associated with the decommissioning of the Childs and Irving Power Plants downstream of the Fossil Springs Diversion Dam.

Researchers conducted surveys for the Common Black Hawk between 1 March and 13 June 2005 along the riparian corridor 0.5 miles upstream of the Fossil Springs Diversion Dam and 0.5 miles downstream of the Childs and Irving Power Plants. The five formal surveys and three informal surveys (incidental surveys conducted during the cuckoo surveys) resulted in 32 Common Black Hawk detections and four active nests. The researchers confirmed that one of the nests produced a nestling and one nest produced a fledgling; the outcomes of the other two nests were not determined.

Three of the four Yellow-Billed Cuckoo surveys were completed during the 2005 breeding season, between 25 June and 28 July 2005 (one survey was canceled due to fire closures). The surveys resulted in no detections of the species along the upper reaches of Fossil Creek. Because the riparian habitat along Fossil Creek appears to be suitable for the Yellow-billed Cuckoo, the reasons for its lack of presence in the area are unclear. However, habitat destruction in other areas has decreased the population of the bird, causing appropriate habitat to remain vacant.

Johnson, M. J., J. Holmes and C. Calvo. 2005.  Common Black-Hawk and Yellow-billed Cuckoo distribution and abundance in the Upper Reaches of Fossil Creek, AZ, 2005. 22 pp.