The following bit was pulled from the Birding Community e-bulletin. It is well known that Rufous Hummingbirds are annual in the state in fall. The chance for extreme rarities such as Allen’s Hummingbird, Calliope and Anna’s Hummingbirds and even extreme rarities such as violet-ears or mangos are possible visitors. Keep those hummingbird feeders up through late fall!
“Our tip of the month concerns hummingbird feeders, and keeping them filled at least well into the fall, if not longer. East of the Mississippi, it is generally well known that only one hummingbird species is present – the Ruby-throated Hummingbird. Ruby-throats are typically present in the U.S. from April into late September. But that has now changed. Starting in the fall, especially after the end of September, other hummingbird species are increasingly possible. Rufous Hummingbirds, for example, are now regular in the East in the fall. Our advice: keep those feeders up through this month and well beyond!
Besides the Rufous Hummingbirds, the possibility of Calliope, Black-chinned, or Allen’s hummingbirds is also an option. The idea of keeping hummingbird feeders active pertains to other areas beyond the eastern U.S., too. It also holds for the Midwest, and is true along the Gulf Coast, a region that is often rich in wintering hummingbirds. Even the Northwest and south-coastal Alaska can be exciting for wandering hummers.
Away from their expected ranges, additional species such as Anna’s, Broad-tailed, Broad-billed, Buff-bellied, Magnificent, and Blue-throated Hummingbirds add to the temptation for backyard birders to maintain and monitor hummingbird feeders late in the season when many vagrant hummers are most likely to occur. Virtually no hummer is out of the question, as vagrant appearances of such super rarities as Green Violetear and Green-breasted Mango will attest.
At the same time, this tip includes the regular admonitions: keep those feeders clean; rinse them every time you refill them; maintain a 4-to1 ratio of water to sugar; use just white sugar (no brown or powdered sugar, molasses, syrup, honey, red food-coloring, or artificial sweeteners), and don’t use insecticide sprays anywhere need the feeders.”