This table summarizes avian species from the Drylands Institute Study (DIS), the current list from 2 eBird hotspots (Vekol South Well and Vekol-Maricopa), and a February 2008 survey by 8 by highly experienced birders of an area associated with the Vekol-Maricopa hotspot.

The Drylands Institute Survey (1) was conducted by " searching the scientific and agency literature, collecting specimen information from the University of Arizona, interviewing biologists who have done field work in the area, and adding the results of our own research activities". They tallied a 159 species.

Another survey through the Arizona Field Ornithologists (2) organization (AFO) was conducted by 8 highly experienced individuals in February 2008. The survey report, easily accessed via a google search, reported 44 species at an area 12-15 miles south of I-8. The area they surveyed included several levees (= berms) surrounded by most mesquites, creosote flats, and tobosa grass habitats. My survey only slightly overlapped their survey area and would include only what is designated Vekol-Maricopa eBird hotspot. The other key aspect is that this was a one day winter survey. They only added 3 species (Ring-necked Duck, Northern Shoveler, and Ferruginous Hawk) that I have yet to detect and that seem only a matter of time before they show up in my surveys. It is only surprising that more survey groups have not explored Vekol Wash.

In the Cornell web site eBird, 142 species were reported for the hotspot Vekol South Well and 116 species for Vekol Maricopa. I have personally documented 138 of the 142 at the Vekol South Well and 94 of the 116 at the Vekol Maricopa sites. So despite my inability to explore the Vekol Maricopa area, I still have a pretty good read on what is showing up there. With the addition of what the AFO survey found, a more complete picture is emerging of this area.



Comparison of eBIrd survey with the DIS study

The DIS survey seemed to have included birds not only in Vekol valley, but also those in the Sand Tank Mountains to the west, Table Top Wilderness to the east, and the Maricopa Mountains to the north. Several of the species (Golden Eagle, Band-tailed Pigeon, Flammulated Owl, Broad-tailed, Rufous, Calliope, and Allen's Hummingbirds, Virginia Warbler, Cordilleran Flycatcher, Gray Vireo, and Mountain Chickadee) reported, while not impossible, are very unlikely in the low elevation Vekol Wash area. This subtraction of 11 species brings their species down to 148 species. The DIS survey does not focus on any one area of Vekol Wash with the birds they list whereas my study, using eBird, focuses on the two hotspots centered in Vekol Valley.

Despite the obvious differences in the two surveys, there were 121 shared species. Because the DIS, included the higher elevation areas in their surveys, 11 of their species should not be expected at Vekol Wash. Conversely, there are 15 species that should show up in both Vekol hotspots: Green Heron, Ring-necked Duck, Northern Shoveler, Least Sandpiper, Black-Necked Stilt, Inca Dove, White-throated Swift, Red-Naped Sapsucker, Brewer's Blackbird, Hermit Warbler, Common Yellowthroat, Willow and Dusky Flycatchers, European Starling, and House Sparrow. The first 5 species on this list are highly dependent on it raining enough to keep water in the cow tanks. It is surprising that the others on this list have not been detected given my field hours (357 hrs at South Well and 44 hrs at Marciopa) in this area.

Perhaps the more interesting difference between these studies are the 18 species not found in the DIS study or the AFO survey: Great Egret, Black-Crowned Night Heron, Peregrin Falcon, Gray Hawk, Crested Caracara, Eurasian Collared Dove, Ruddy Ground Dove, Yellow-Billed Cuckoo, Belted Kingfisher, Cedar Waxwing, Indigo and Painted Buntings, White-Throated Sparrow, Bronzed Cowbird, American Redstart, Summer Tanager, Rufous-Backed Robin, and Cassin's Vireo. It is puzzling that most of these species were not detected by DIS given their 4 approaches (see earlier) for documenting avian fauna. It is quite possible that some of these species had not had Vekol as part of their range or habitat in 2001.



Finally, Witzeman and Corman (2017), in the third edition of "Birds of Phoenix and Maricopa County Arizona" extensively cover the birds of these areas with the notable exception of the Vekol Valley. They do mention the Sand Tank mountains to the west of Vekol and south of Gila Bend. Given their extensive treatment of the avian fauna, it is surprising that there is not a section on Vekol Wash. Ii is curious that more AFO surveys exploring this area have not been performed.

There are several speciality species for Maricopa County that consistently (Although time of year is usually important) show up at South Well: Varied Buntings, Rufous-Winged Sparrows, Pyrrhuloxia, Purple Martins, Common Ground Doves, Indigo Buntings, and Lawrence's Goldfinches. Varied Buntings show up in late May and migrate out in late September. I have never had them at the 5.7 mile wash. Rufous-winged Sparrows are year round residents. They are toughest to detect in June as they are mostly silent during their nesting period, but are easily detected by sight and sound the rest of the year. I have only two records of them at the cow tank (levee) where most of my time is spent and dozens of records at the 9.0 mile Mesquite stand. Pyrrhuloxia are year round residents, but are less predictable as to when they show up, then mostly at the cow tank. Purple Martins are spring to summer nesters, but you most often see them flying over the cow tank in May and September. They likely nest in Saquaros in the Table Top Wilderness and Sand Tank Mountains although I have not visited there often enough to be sure. As long as the cow tank has water or green vegetation, Common Ground Doves are reliable visitors. One can expect them during the hotter conditions coming to the cow tank for water. Indigo Buntings are seen in April through September, but not predictably. Finally, Lawrence's Goldfinches are consistent late fall to winter visitors to the cow tank.



Maricopa rarities detected here are: American Redstarts, Cassin's Sparrows (Although DIS did detect them in 2001), Painted Bunting, Gray Hawk, Crested Caracaras, Rufous-Backed Robin, Ruddy Ground Dove, and White-throated Sparrow. Cassin's Sparrows have only showed once, but in very large numbers, in the summer of 2019. I have not seen or heard them since that invasion from southern Arizona. American Redstart, Painting Bunting, Rufous-backed Robin, and the Ruddy Ground Dove are all single observations, but given the habitat created when the cow tank is holding water, they are not a surprise for Vekol. The White-throated sparrow was observed several times during December 2019 and January 2020 and probably was repeated observations of a single individual.


(1) 2001. Richard S. Felger (Drylands Institute), Dale S. Turner (School of Renewable Natural Resources University of Arizona, Tucson, AZ 85721), Linda Leigh (Drylands Institute), Kathryn Mauz (Arid Lands Resource Sciences, Office of Arid Lands Studies University of Arizona), Carianne S. Funicelli (Drylands Institute), Robert X. Barry (56th Range Management Office Luke Air Force Base, AZ 85309), Robert Bezy (Herpetology, Natural History Museum of Los Angeles County Los Angeles, CA 90007), Erik Enderson (3234 East Patricia St, Tucson, AZ 85712), Jim Malusa (Renewable Natural Resources, Sonoran Desert Field Station University of Arizona), Tom Van Devender (Arizona-Sonora Desert Museum 2021 Kinney Road, Tucson, AZ 85743), Michael F. Wilson (Drylands Institute) Biological Resources of the Sonoran Desert National Monument, Arizona, Working Draft June 2001 Drylands Institute PMB 405, 2509 North Campbell, Tucson, AZ 85719
(2) Tomoff, Carl 2008. Arizona Field Ornithologists. Vekol Valley Survey Summary.
(3) Witzeman, Janet and Troy Corman 2017. Birds of Phoenix and Maricopa County Arizona, 3rd Edition. Maricopa Audubon Society.