Black hummingbirds are extremely rare in nature. While most hummingbirds display vibrant, iridescent colors like emerald, ruby, and sapphire, melanistic hummingbirds with all-black plumage are scarcely documented. Here’s an overview of black hummingbird sightings and why this variant plumage occurs.
How Rare Are All-Black Hummingbirds?
Out of over 320 hummingbird species across the Americas, only a handful of melanistic hummingbirds have been reported. Some species with documented black variants include:
- Black-chinned hummingbird
- Anna’s hummingbird
- Costa’s hummingbird
- Rufous hummingbird
- Allen’s hummingbird
Even within these species, all-black individuals are exceptionally uncommon. For example, among the over 30,000 banded rufous hummingbirds, there are only three reports of solid black plumage. The scarcity of melanistic hummingbirds indicates it is a very rare genetic mutation in wild hummingbird populations.
What Causes Melanistic Plumage in Hummingbirds?
Melanin is the pigment that produces darker feather coloring. Melanistic hummingbirds have an excess of melanin that covers their normally vibrant plumage. Known genetic causes of melanism include:
- Mutation of the MC1R gene, which regulates melanin production
- Overexpression of the melanocortin-1 receptor, which binds to melanin-stimulating hormones
These genetic changes can occur randomly through mutation and be inherited if melanistic hummingbirds survive to breed. In other birds, higher melanin levels may also be induced by factors like temperature, diet, and hormone levels.
Does Melanism Have Advantages for Hummingbirds?
In most hummingbird species, the striking, metallic plumage colors are adaptive for attracting mates and establishing breeding territories. Male hummingbirds with the brightest, most iridescent feathers often have higher reproductive success. This suggests all-black melanistic plumage would be maladaptive and selected against in populations.
However, melanism may have some benefits that allow the trait to persist in low frequencies:
- Thermoregulation – Increased melanin provides more UV protection and resistance to overheating.
- Immune function – Melanin’s antioxidant properties may boost immune defenses against pathogens and parasites.
- Mate attraction – Novel black plumage could attract curious mates in some cases.
But any advantages are likely outweighed by the loss of colorful mating displays in most habitats. Overall, melanism appears to be a relatively non-adaptive mutation in hummingbirds.
Where Are Melanistic Hummingbirds Most Often Reported?
While possible anywhere hummingbirds occur, black plumaged individuals seem to be observed more frequently in certain regions. Some hotspots for reported melanistic hummingbird sightings include:
- Southern California – Especially San Diego and Palomar Mountain regions.
- Arizona – Around the Phoenix, Tucson, and Sierra Vista areas.
- Texas – In Big Bend National Park and the Chisos Mountains.
- Mexico – In states like Guerrero, Jalisco, Michoacán, and Oaxaca.
The greater documentation in these areas may reflect a founder effect, where higher initial frequencies of melanistic alleles in certain populations lead to more sightings. The warm, arid climates could also favor selection for adaptive melanism.
Famous Examples of Black Hummingbirds
While nearly all reported black hummingbirds remain unverified one-time sightings, a couple exceptionally documented examples stand out:
- Lady Blacktip – A female rufous hummingbird extensively observed for over a month near La Jolla, California in 2019. Her nearly all-black plumage featured white tail tips.
- Orange County black Allen’s hummingbird – A melanistic male Allen’s hummingbird well-documented by birders in Orange County, California with photos and genetic samples collected over several years.
These two birds represent the most thoroughly confirmed cases of black hummingbirds, providing evidence that nearly all-melanistic individuals can survive to maturity in wild populations.
Verifying Sightings of All-Black Hummingbirds
Hummingbirds with partially darkened plumage are not uncommon. Northern flickers and other woodpeckers are also frequently confused with melanistic hummingbirds. However, completely black individuals are extraordinarily rare.
To verify possible sightings of all-black hummingbirds, consider these tips:
- Get detailed photographic evidence – Multiple high-quality photos or video from different angles.
- Note key identification features – Size, shape, wing beats, and feeding behaviors.
- Record location and date – Document habitat and timeframe details.
- Consult hummingbird experts – Ask local birding groups to help confirm identification.
Careful documentation is necessary to validate sightings of these exceptionally rare black hummingbird variants and understand their occurrence in wild populations.
Conclusion
Solid black plumage is an exceptionally rare genetic variant in hummingbirds, observed in only a tiny fraction of individuals. Melanistic hummingbirds result from mutations increasing melanin levels, which could potentially have some adaptive benefits but more often impairs colorful mating displays. Continued documentation and study of these unique all-black hummingbirds may reveal more about their genetics, adaptive value, and evolutionary role as a rare phenomenon among highly colorful species.
