Arizona Field Ornithologist
©2008
HOME | REPORT SIGHTINGS | PHOTOS | BIRDING | JOURNAL | ABOUT US | CHECKLISTS | MIGRATION COUNT | EVENTS | LINKS

Santa Cruz Flats Raptor Count


Crested Caracara - Photo Kurt Radamaker

Many hawk species winter in southern Arizona, some in relatively large numbers, augmenting resident populations. Santa Cruz Flats in Pinal County is particularly noteworthy for drawing these winter visitors. Located along the basin of the Santa Cruz River, which flows northwest across the county towards the Gila River, the area encompasses approximately 350 square miles and has an average elevation of 1,700 feet. It is primarily agricultural, and fields of cotton, alfalfa, corn, and sorghum, laced with irrigation ditches, share the area with two large sod farms, several pecan and pistachio groves, a dairy farm, and a couple of cattle feed lots. Abundant rodents, thousands of wintering sparrows, and a big population of doves offer a ready food supply for raptors. Palms, cottonwoods, and clumps of tamarisk and Mexican palo verde provide roosting sites for owls.

Crested Caracaras, first reported from this area in January 2001, appear to be increasing. Although the numbers observed in the winter are higher than other seasons, they have been seen year-round suggesting possible nesting in the area. A resident population of Black Vultures is found in the area, although at this point its nesting sites and total numbers are apparently unknown. Generally, larger groups are seen in the winter. Turkey Vultures, while common in summer and very numerous during migration, are unusual in the winter. 

Birders often visit this area in the winter to look for raptors as well as nonraptors such as thrashers, Mountain Plovers, and Mountain Bluebirds, but no systematic count of raptors had ever been made before and no part of the area is in a Christmas Bird Count circle. However, annually assessing the number of raptors wintering in this area is useful for judging population trends and migratory patterns. It’s with this in mind that on 21 January 2006 nine birders, organized into three teams, conducted the first tally of raptors in the area. Since then the count has become an annual activity held on the third Saturday of January.

For each of the first three years of the count three teams surveyed the area. In response to increased interest 34 square miles were added to the northern section of the count area in 2009, and four teams conducted the survey in slightly altered sections. Some predawn owling was begun in the third year of the count. The area covered by the survey is bounded on the south by the Pinal County-Pima County line and on the west by Trekell Road to Battaglia Road and then jogs west to Chuichu Road. The northern boundary runs along Shedd Road from Chuichu Road to Wheeler Road then jogs south to run along Baumgartner Road from Wheeler Road through a line extending from Baumgartner to I-10. The eastern boundary is Wheeler Road from Shedd Road to Baumgartner and then a diagonal line along I-10 (from where it would intersect with Baumgartner if the latter were extended east) to the Pima County line.

Naturally, such a count is approximate; some areas away from roads are not reached, and it’s possible that a few birds are counted twice. But as the data for the wintering raptor population accumulates, we are hoping long-range trends will be clearer.

For more information, please contact the survey coordinator, Doug Jenness, d_jenness@hotmail.com.



If you are interested in participating in the Santa Cruz Flats Raptor Count, Contact

Area Coordinator
Doug Jenness
l:d_jenness@hotmail.com


Count Results

 

Updated Saturday, April 18, 2009
©2005
HOME | REPORT SIGHTINGS | PHOTOS | BIRDING | JOURNAL | ABOUT US | CHECKLISTS | AZ BIRD COMMITTEE | EVENTS | LINKS