Certain look-alike hummingbird pairs can be maddeningly difficult to distinguish, even for experienced birders.
With over 300 hummingbird species in the world, some so alike that even DNA analysis is required to tell them apart1, accurate identification can be an epic test for birders.
Luckily, researchers have been studying the field marks and behaviors that separate these confusing cousins. Their findings can help you sharpen your ID skills the next time one of these fascinating birds come into view.
What Makes Some Hummingbirds So Tricky to ID?
The main reason certain hummingbird species are hard to tell apart is their remarkable physical resemblance.
We’re talking:
- Nearly identical sizes and shapes
- Extremely similar plumages and colors
- Overlapping ranges and habitats
For example, the black-chinned and ruby-throated hummingbirds are both slender, green-backed hummers with iridescent red throat patches (gorgets). Their look-alike plumages make visual identification a challenge, especially from a distance.
The Key Is in the Details
While these hummingbird doppelgangers may appear alike at first glance, closer inspection can reveal subtle but crucial differences:
Gorget Shape & Color Extent
- Black-chinned: Thin, straight gorget line
- Ruby-throated: Broad, rounded gorget patch
Tail Feathers
- Black-chinned: Green tail with black-purplish outer feathers
- Ruby-throated: Grayish-green tail with white tips
Similarly, the lookalike Allen’s and rufous hummingbirds can be separated by variations in:
- Rufous coloring on the sides and flanks
- Tail feather colors and patterns
- Vocalizations and wing sounds
When Looks Aren’t Enough: Using DNA
With some hummingbird twins, the similarities are so extreme that even experienced eyes can’t reliably tell them apart based on looks alone. That’s when researchers turn to DNA analysis.
Researchers in Peru found a hummingbird with an unusual golden throat and initially thought it was a new species. But a DNA analysis revealed it was a hybrid between the pink-throated brilliant (Heliodoxa gularis) and rufous-webbed brilliant (Heliodoxa branickii) hummingbird species, which normally have pink throats. (ref)
This molecular approach is proving to be a powerful tool for untangling hummingbird identification puzzles. Although it requires capturing the birds, a small feather sample provides the DNA needed for analysis.
Where Do Certain Species Live?
A hummingbird’s geographic range and preferred habitat provide vital context clues for identification. Some species are found only in specific states or regions, while others are wide-ranging migrants that travel long distances seasonally.
Habitat preferences like urban vs. rural environments, vegetation types, and elevation ranges can also narrow down your options.
For example, you likely won’t see a Rivoli’s hummingbird in the desert or a ruby-throated hummingbird in California yards.
How Can You Become a Pro Hummingbird Identifier?
The key to accurate hummingbird identification is observing and considering multiple traits—size, plumage, behavior, vocalizations, location, and more. Don’t rely on just one characteristic.
Field guides and online resources can teach you the distinguishing features of each species in your region. Photos and range maps are invaluable tools.
As you gain experience watching hummingbirds, you’ll start to recognize the subtle differences between species. Note the time of year, as this can indicate whether you’re seeing a year-round resident or a migrant just passing through.
Most importantly, have patience! Hummingbirds move quickly, so it may take several observational sessions before you can confidently identify individuals.
Source:
- https://phys.org/news/2023-02-pink-gold-hybrid-hummingbird-feathers.html
Davin is a jack-of-all-trades but has professional training and experience in various home and garden subjects. He leans on other experts when needed and edits and fact-checks all articles.