Field Expedition to Yuma County Summary
November 17-18, 2007
From November 17-18, twelve members of the Arizona Field Ornithologists (AZFO) converged in Yuma from different regions of the state for the latest Field Expedition. The Expedition was well attended, pulling in folks from the Flagstaff, Phoenix, Tucson, and Yuma areas.
On Saturday morning (17 November), we split into two survey teams: a team of three heading into the Kofa Mountains, and the remainder to locations within the lower Colorado River Valley. The Kofa Queen Canyon hikers encountered a Black-Chinned Sparrow, which is a very local breeding species in Yuma Co. with few if any November records. Even more exciting was a single male Cassin’s Finch, a casual late fall and winter visitor. This species which has only four records (totaling 28 individuals) listed in “Birds of the Lower Colorado River Valley”. At the end of the day, this team also visited Martinez Lake and vicinity, with highlights including both Western and Clark's Grebes, 1 Hooded Merganser, 2 Least Bitterns, and a bighorn sheep!
The other team surveyed the Yuma East Wetlands, Cottonwood Island, and Gateway Park in the morning. Highlights included a late Nashville Warbler (few if any November records in the County) and a Yellow Warbler (rare this late in season) among so many Yellow-rumped Warblers. After lunch, this team broke into two separate teams and thoroughly surveyed the impressive linear stand of cottonwoods at the Yuma West Wetlands. There they encountered Pine Siskin, and 1 each of Cassin’s and Plumbeous Vireo. A survey of active agricultural fields west of San Luis revealed one alfalfa field containing an impressive concentration of 25-30 raptors including 10 Ferruginous Hawks, 1 adult Golden Eagle, 2 Prairie Falcons, and numerous Red-tailed Hawks in many different plumages. A small flock of Tree Swallows also passed over. The day ended in south Yuma along the Yuma Main Drain where the teams relocated an immature Red-Shouldered Hawk and the wintering Thick-Billed Kingbird noted by Dave Powell the day before. A fly-by Peregrine Falcon made it a 12 raptor day!
Sunday morning found everyone at Betty's Kitchen surveying the riparian revegetation sites and then off to nearby Mittry Lake. Waterfowl at Mittry was abundant, with approximately 2000 American Coots, amongst which were a few Redhead, American Wigeon, and Ruddy Duck. A briefly calling Clapper Rail and a few Least Bitterns added to the mix. By far the star of the area was a totally unexpected dark-morph Rough-Legged Hawk seen perched, then soaring overhead and photo-documented well by many team members. One team headed to the Welton area along the Gila River, while the remaining group continued surveying more sites in the nearby area. At the Dredge Launch they discovered an American Bittern. In the Golden Shores area, a few team members found a late Violet-Green Swallow among N. Rough-winged Swallows and the sixth warbler of the Expedition, an American Redstart.
By early afternoon, the remaining teams ended up at Quigley Wildlife Management Area near Tacna within the Gila River Valley. Highlights there included a White-Tailed Kite, 16 Sandhill Cranes, 2 Snow Geese, and a Pine Siskin. As Henry noted, the raptors were the biggest hit over the weekend with a final total of 14 species, including a few rarities for the area.
AZFO thanks the Field Expedition team members who assisted in exploring and collecting data in this unique corner of the state. They were Carol Beardmore, Troy Corman, Henry Detwiler, John Grahame, Richard Lasky, Tracy McCarthey, Jake Mohlmann, Elaine Morrall, Liz Payne, Dave Powell, Daniela Yellan, and John Yerger. AZFO owes a special thanks to Yuma birder Henry Detwiler for his invaluable assistance in organizing the Expedition. Thanks also to Liz Payne for contributing the photos seen here.
All credit goes to these team members for another very successful Field Expedition! Please join us for our next Field Expedition, to the Vekol Valley on February 2-3, 2008