By Bob Sargent
(excerpt from Netlines)
This is the second in a series of articles on some of the species that we are encountering in our study. Allen’s is by far the most controversial of all the hummers we capture and band. It is in the same genus (Selasphorus) as Rufous and Broad-tailed hummingbird and is very similar in both size and appearance to Rufous. The following is based upon both field observations and banding encounters in winter only. It is not intended to be the final word. Our experiences with Allen’s on its nesting grounds are very limited, and are not a factor in this article.
Our good friend Nancy Newfield in Louisiana, who helped start us on this wonderful journey of discovery, warned us of the controversy surrounding any immature or female Allen’s that we might encounter. I can only imagine the hassle that she must have had when she first started documenting this species
Let’s begin by saying that Allen’s had never been documented in our original five state area when we started our hummer banding. These states were Alabama, Georgia, Florida, Mississippi and Tennessee. The Allen’s we banded in these states were all documented first records. This is certainly not intended to suggest that they were not there before we came. In fact, it is our contention that they have been in the Southeastern U.S. all along, they just went undetected. What is new here is the search and discovery process itself. The hummer-loving public has now become an important part of the Ornithological community simply by leaving hummer feeders out during the winter months. They now have someone to call when one of these ‘funky’ birds shows up after the Ruby-throats have flown-the-coop. My wife, Martha Gail, and I have been the instrument of identification and documentation only. The discovery is yours, dear friends. SALUTE!
The first Allen’s we documented was at the residence of Mary LeGault in Mobile in 1991. It was a female and was very difficult to identify in the field. The belief at that time was that a female could not be field identified. That belief is still held by most ornithologists and birders today and rightly so. This bird and all the other Allen’s that we have banded except one were identified as Allen’s prior to being captured and banded.
As described in the previous article on Rufous hummingbird, adult males of both Rufous and Allen’s are a piece-of-cake. An adult male Rufous will have a full gorget of rufousy, reddish-orange appearing feathers that are like glowing coals in a hot fire! He will have no white tips on his tail feathers. His back will be all brownish rufous in color, except for possibly a few scattered green feathers. He will be brash, bold, very vocal and mean as sin. He will continually perch in the open on an exposed twig to hawk insects and protect his territory. He is just as likely to attack a Red-tailed hawk as another hummer that enters his turf. He is fearless and very aggressive. He thinks he is Godzilla. He is Rufous hummingbird, and he is the big boss man!!
An adult male Allen’s is smaller overall. He will have the ‘throat-on-fire’ appearance of an adult male Rufous, but the back will be solid green. This green is in the form of an elliptical shaped disk that covers the central back. Some rufous color may extend just above the folded wing when the sides and flanks are ‘fluffed’, but only slightly. The rump area will be rufous colored and it will extend well up on the lower back area. The rufous colors present on the face, the sides, flanks and in the rump and tail tend to be much more chestnut brown than the more orange-brown colors found in Rufous. In my opinion, the tail will appear much more pointed than that of an adult male Rufous. This tail in an adult male will be all dark, with no white tips. This pointed tail appearance was first suggested to me by Nancy Newfield. The outside tail feathers are very, very narrow. In winter, when we see Allen’s, they are much more subordinate than their brash cousin Rufous. They tend to keep a much lower profile. They perch inside evergreen shrubs, and glean insects from the bark and leaves of these plants. They are much less likely to openly hawk insects from an exposed perch than Rufous, and rarely are they as combative when an intruder enters their territory. If the bird has a full gorget and the back is green, it is almost certainly an adult male Allen’s. I have heard and read many times of adult male Rufous with an all green back, I remain unconvinced. It is my opinion that if one of these green backed Rufous existed, it would be so rare (outside the 95% statistically) as to not be a factor in the general field identification of adult male Rufous/Allen’s hummingbirds. A possible explanation could be a hybrid or simply an Allen’s, misidentified as a Rufous. Hey, it could happen. You’ve got to have good accurate calipers and really know how to use them when measuring the width of these needle-like tail feathers. Most banders do not have this type of caliper. Just remember, male Selasphorus hummers will normally molt in a whole new set of back feathers before they get their new gorget feathers in the throat.
Female Rufous and Allen’s look alike!! Tread easy here when trying to identify them in the field. Most observers will not have enough experience to sort them out.
Adult female Rufous and Allen’s will have all green back with little or no rufous color visible in the tail feathers. The outer three tail feathers on both sides will be white tipped. In both species, about 1/3 to ½ of the basal portion of the outer tail feathers will show rufous color and will normally be seen only when she spreads the tail. The very narrow and normally shorter outside tail feathers of female Allen’s gives the tail a more pointed appearance than Rufous. Both Rufous and Allen’s will have some rufous color on the breast, sides and flanks. Occasionally, females of both species will show some rufous in the area of the cheeks and face. Although there is some degree of overlap in size, in most cases Rufous hummingbirds are noticeably larger than Allen’s. Rufous tend to have longer wings, longer tail and longer bill. In addition, the ‘rufous’ color in female Allen’s tends to be darker and more chestnut brown in tone. Many females of both species will have some iridescent ‘gorget’ feathers located primarily in the lower center part of the throat. These feathers will not be as shiny and flashy as those in the males. If there are gorget feathers present on the sides of the throat below the eye, the bird is probably a young male.
Immature male Rufous and Allen’s look almost identical. Young Allen’s will always have an all green back. Most young Rufous that we have encountered have had at least some rufous colored feathers in the back. Young males of both species will have the basal 2/3 to ¾ of the tail rufous colored. Both will normally have some long, rufous colored feathers in the rump that will extend out over the base of these tail feathers. That color in young Allen’s will tend to be more chestnut rufous colored.
Like other families of birds such as shorebirds and sparrows, it takes a lot of experience to become proficient at identification. However, I believe that good observers, familiar with hummingbirds, can safely separate many Rufous/Allen’s in the field. There are no field guides or bird books that have photographs that will enable you to identify female and immature Rufous and Allen’s hummingbirds at your feeders.