Hybrid Hummingbird

22 08 2015

Anna’s x Costa’s Hummingbird – Luke Tiller

On August 10th 2015 I was shooting some hummingbirds in my yard when a bird popped in to check out the feeder that immediately struck me as somewhat odd. Initially the flash of the color in the gorget had me thinking about Costa’s Hummingbird, but something about it wasn’t quite right. Costa’s tend to be pretty uncommon in the yard themselves, so I was quite keen to try get a shot or two of the bird in question even if it just turned into a funky Costa’s. Though the initial view was quite brief the gorget coloration appeared to change somewhat as the bird changed angles, going from something almost typically Costa’s purple to something that took on a distinctly pinkish hue. Compare the color of the gorget of the hybrid bird above with the adult male Costa’s I photographed this spring below.

Costa's Hummingbird - Luke Tiller

Costa’s Hummingbird – Luke Tiller

I was aware of the possibility of hybrid hummingbirds as the week or so before, local birder, John Garrett had photographed an interesting hummingbird which he’d identified as an hybrid Anna’s x Costa’s (photo here) just a mile or so from where this one had appeared. To my eye his bird essentially looked much like an Anna’s Hummingbird with a Costa’s colored gorget and a white upper breast and line down the belly which hints at it’s mixed parentage. The admixture of colors in my bird had me wondering whether I might have another potential hybrid, but this time leaning more heavily towards Costa’s in appearance.

After about ten minutes, which felt much longer, thankfully the bird returned. This time it allowed me to gather a few admittedly poor photographs. At least now though I had something to send people to show the gorget coloration. As the bird continued to return over the afternoon I managed to gather a few decent shots of the bird and started to note a few interesting features beyond the gorget coloration including what appeared to be an important one – the length of tail. Though in the process of replacing many of its tail feathers the birds outer retrices extended notably past the wings. This is a good feature for Anna’s Hummingbird (note this feature in this linked picture), but problematic for Costa’s which are notably short tailed/long winged (see link). Costa’s wing tips reaching the tip of their tail or extend beyond the tail tip (compare the longer two outer retrices extending distinctly beyond the wing tips on the picture of the bird below).


Anna’s x Costa’s Hummingbird – Luke Tiller

The bird certainly had many Costa’s features to it. I noted that the bird was distinctly white-breasted on the upper breast with a white line down the central breast down to the vent almost creating a vested appearance which is much more in line with Costa’s Hummingbird (features you can see quite nicely in the link on this bird I photographed in spring). Compare this to Anna’s below which typically shows a dingy upper breast and no central white stripe (you can also compare the gorget coloration to the hybrid). Speaking to local birders it seems that this white breasted and vested look is one often exhibited by suggested Anna’s x Costa’s hybrids and is hinted at in John Garret’s shot. The gorget shape with the long ‘tails’ is more suggestive of Costa’s Hummingbird than it is of Anna’s Hummingbird, though it is not as extensive on the crown or on the back of the head as it seems to be on most adult Costa’s.

One of the main things in favor of Costa’s was the overall size of the bird. Though it is not completely evident in the pictures the bird was noticeably on the small side. There are admittedly only 0.5 inches separating Anna’s and Costa’s in size, but that 0.5 inches is pretty noticeable at close range (down to ten feet or less) on a feeder.


Anna’s Hummingbird – Luke Tiller

Though there is a lot that weighs heavily in favor of Costa’s Hummingbird (more than one correspondent suggested it was perhaps just a young male) I and most other birders I have had contact with believe that there is enough admixture in the gorget, as well as the odd tail/wing length, to suggest this is a hybrid Anna’s x Costa’s. Interestingly the same day the hybrid appeared I first noticed and photographed a female type Costa’s Hummingbird in the yard. This one I only saw briefly and managed to take a quick record shot of while it was perched in pretty marginal lighting (see photo below). It then seemed to disappear for a few days but it (or another very similar looking bird) showed up again  a few days later. The female type was seemingly generally reluctant to come in to the feeders so it may be that it has been around but passed unnoticed at times.

Talking to local birders the timing of the arrival of the hybrid and this female wasn’t at a time generally associated with movement of Costa’s Hummingbirds, so where these birds came from and why, who knows. Unfortunately I never knowingly heard the hybrid bird vocalize so I’m not sure what it sounded like, it would have been useful to hear it and even better to have a recording.


Costa’s Hummingbird – Luke Tiller

Though there are only a few records of this particular hybrid on eBird (see link) at least one local birder thinks that it is probably relatively common within the world of hybrid hummingbirds. The two species are both in the genus Calypte and are closely related. There are at least two other records from LA County both from the San Gabriel Mountains and the San Gabriel Valley. It was a neat experience and I’m certainly glad I managed to capture a few decent photographs of it over the next couple of days before the bird departed on August 13th. You can view those other pictures on my flickr account (here).