Violet-crowned Hummingbird Guide (Ramosomyia violiceps)

Latest posts by Kathryn Peiman (see all)

Info

This is a rather unique-looking hummingbird species because they don’t have the typical bright metallic and iridescent throat feathers that hummingbirds are known for. Instead, with an intense violet crown, white throat, and red bill, they look slightly cartoonish.

This is also another hummingbird species that barely makes it into North America and has only been identified as breeding there relatively recently. The first reports of violet-crowned hummingbirds breeding in Arizona and New Mexico were in 1959, though specimens were taken in North America as early as 1905. I am a biologist trained in evolutionary ecology, and I find range expansions especially interesting, as we rarely know the implications of individuals moving into new areas. Let’s learn about this hummer that doesn’t look quite like the other hummingbird species, and is a recent addition to our breeding list.

Bottom Line Up Front

The violet-crowned hummingbird ranges from southeastern Arizona and southwestern New Mexico down through Mexico and has only been known to breed in North America for the last ~50 years. It is the only hummingbird in the United States without a metallic throat patch; if you’re somewhere else, look for the brilliant violet crown, red bill tipped with black, and white throat/belly to identify this species. When there’s a lot of nectar available, they can be found together in large numbers, possibly as part of a breeding display.

Violet-crowned Hummingbird Taxonomy

Violet-crowed hummingbirds are classified using the following taxonomy:

  • Kingdom Animalia
  • Phylum Chordata
  • Class Aves
  • Order Apodiformes
  • Family Trochilidae
  • Subfamily Trochilinae
  • Tribe Trochilini
  • Genus Ramosomyia

Hummingbird taxonomy is still being reviewed and revised, with newer molecular techniques showing that many previous classifications based on morphology or behaviour were incorrect. We now know that violet-crowned hummingbirds belong to one of the most recently diversified and overall diverse groups of hummingbirds, the ’emeralds’ (Tribe Trochilini), which includes 110 species in 35 genera.

Violet-crowed hummingbirds were formerly placed in the genus Amazilia until a study in 2014 showed the genus was polyphyletic, which means there was more than one common ancestor of the species in that group – something taxonomists want to avoid – and so it was proposed in 2017 that violet-crowned hummingbirds (and two other species) be placed in the genus Leucolia instead. However, in 2021 it was noted that that genus name was already taken, so the genus Ramosomyia was suggested instead. As this is a very recent name change, it has not yet been formally included within all sources that publish avian nomenclature, so you might still see Leucolia and even Amazilia used in some places.

The genus Ramosomyia has three species. The green-fronted hummingbird looks very similar to the violet-crowned hummingbird, but their ranges do not overlap; green-fronted hummingbirds are confined to a very small part of Mexico. In fact, in the mid-1900s, some considered these to be the same species, but molecular evidence suggests that they are separate though perhaps in only parts of their range as there is also evidence of ongoing hybridization. The third species, the cinnamon-sided hummingbird, was formerly considered a subspecies of the green-fronted hummingbird, but they are also likely separate species based on molecular evidence.

Initially, people thought there were three subspecies of violet-crowned hummingbirds, now there are only two recognized: R. v. violiceps and R. v. ellioti. What does this all mean? That diversification and speciation are complex, take time, and are a continuum from fully separated to still interbreeding populations.

How to Identify Violet-crowned Hummingbirds

Violet Crowned Hummingbirds

The violet-crowned hummingbird is a fairly large hummer at 10-11.5 cm long and weighing between 4.2-6.2 g. It does not have a metallic throat patch and is the only hummingbird in the United States that lacks it, making identification in that locality fairly easy.

Their name describes one of their striking features – they do indeed have a violet-blue crown that extends to the back of the head. It is a very intense colour, and it contrasts clearly with their white throat and a bright red-orange bill that generally has a black tip. Other identification features include a small white spot behind the eye, and dull grayish brown to green back and rump, a coppery bronze tail, and a white belly with light olive green flanks.

Like many hummingbirds, adult females are similar to the males but duller overall; they may also have more black on their bill, though these differences are not considered reliable as there is overlap between the sexes. This means you cannot know for sure whether you are seeing a male or female unless you see one engaging in nesting activities as only females raise the young. Juveniles look similar to adults but are a little duller, with more black on a pinker bill and grayish-buff edges to their breast feathers.

The subspecies R. v. ellioti is similar to the above description of R. v. violiceps, except the crown of ellioti is deeper turquoise blue and its tail is bronze-green.

Where Does the Violet-crowned Hummingbird Live: Habitat

Violet Crowned Hummingbirds

The subspecies R. v. ellioti is the more northern of the two subspecies and is the one that is found in North America. To find it, look in riparian areas from southeastern Arizona and southwestern New Mexico, south into Mexico possibly as far as Puebla. It has also been recorded in California and Texas as a vagrant. In Arizona and New Mexico, it occurs between 1,200 and 1,700 m, and in Sonora, it occurs between 200 and 1,300 m.

The more southerly subspecies R. v. violiceps is found in a wider range of habitats, and ranges from extreme eastern and southern Michoacán south into northwestern Oaxaca. In this southern part of its range, it is typically found between 200 and 1,400 m but can be found up to 2,400 m.

The violet-crowned hummingbird can be found in a variety of landscapes including the edges of riparian corridors, cottonwoods and sycamore groves, thorn scrub forest, deciduous and pine-oak juniper forest, small-leaved forest, grassy hillsides, orchards, wooded parks, and gardens. In general, they seem to prefer streamside riparian habitats in most parts of their range, so that’s the best place to look for them.

Violet-crowned Hummingbird Diet and Feeding

We know that all hummingbirds drink nectar, and so of course they require flowering plants regardless of the specific type of habitat they prefer. The violet-crowned hummingbird is no exception, and there are two dozen or more plants that they have been known to visit. This makes them more of a generalist when it comes to food preferences.

In hummingbirds, successful flower defense is almost always based on individual size, and bigger birds win. Fighting among species occurs more often when the food supply is limited, such as during dry periods when plants don’t put the effort into making nectar-rich flowers. When violet-crowned hummingbirds defend flowers, their fairly large size means that they win a lot of interactions, but even larger hummingbird species will still win against violet-crowned hummingbirds – so for getting food, bigger is better.

When hummers are not breeding and food is scarce, they will sometimes travel to locations where flowers are more abundant. These are not migratory movements but can cause large changes in local abundance as they follow food availability.

Violet-crowned hummingbirds will also eat insects, and they capture them by hawking (catching them in the air) and by gleaning (picking them off vegetation). They also eat insects caught in spider webs and eat the spiders themselves.

Violet-crowned Hummingbird Breeding

Violet Crowned Hummingbirds

Breeding timing is likely determined by nectar availability, which makes sense, as hummingbirds require a lot of energy to maintain themselves, and require even more if they’re feeding nestlings. In some places in Mexico, violet-crowned hummingbirds have been seen breeding at all times of the year, but generally, they breed mostly in the late spring and summer (March-September).

We don’t know much about the mating system of violet-crowned hummingbirds. We do know that they are polygynous (males mate with more than one female), which is true of most hummingbirds. However, this species may also practice polygamy (both sexes mate with more than one partner), and there is even some evidence that males may display together to attract females (termed ‘lekking’), but this requires further study.

The male’s only contribution to reproduction is mating – the female chooses the nest site, makes the nest, and does all the incubation and feeding of nestlings. Again, this is the norm in the hummingbird world.

Violet-crowned hummingbirds also exhibit some site fidelity, as some banded birds were recaptured at the same location in subsequent years, but what causes some birds to return and others to go somewhere else is a mystery.

Violet-crowned Hummingbird Nesting

There is limited information available on nesting in violet-crowned hummingbirds, and most of it comes from studies in one location in Arizona, so the generality of these observations is unknown. There is variation in how high nests are built – in Arizona, all nests were located in sycamore trees, at an average height of 7 m. One nest in Mexico was 4 m off the ground, while other nests were closer to the ground, only 1-2 m high.

Descriptions of their nests are few, but they are likely made mostly using soft plant down, such as fibers from pochote tree (Ceiba aesculifolia) fruit. The outside is camouflaged using moss and lichen and sometimes plant seeds attached with spider webs. As you would expect for a hummingbird, nests are tiny – they measured 3.8-4.09 cm in external diameter and 2.1-2.74 cm deep. Interestingly, nests may be reused, possibly because the material to make nests is limited in its availability.

Nests are vulnerable to predators – they’re basically a container with a tasty snack inside, and there is little the female hummingbird can do to prevent her eggs or nestlings from being consumed. Avoiding detection, through camouflage, is the best defense. Sometimes only half of the nests are successful, with predation (eggs or nestling consumed) being the most common reason nests fail. Nests that are built in more exposed areas have higher predation rates, and so the female’s decision about where to put her nest has real consequences for chick survival.

Violet-crowned Hummingbird Eggs

They lay 2 eggs, which is the same as most hummingbirds. After the female lays one egg, there is a two-day gap before the second egg is laid, at which point she starts incubation. This incubation technique means that both eggs hatch at the same time. A closely-related species had a 15-day incubation period, so the violet-crowned hummingbird is likely around the same duration.

After the eggs hatch, the female violet-crowned hummingbird spends more time on the nest than off when the chicks are small (less than seven days old), and as they get larger, she spends the majority of her time off the nest either foraging or perched nearby. Fledging duration is probably over 2 weeks, but this is inferred from other species as it has not been recorded for violet-crowned hummingbirds.

Violet-crowned Hummingbird Population

Violet Crowned Hummingbirds

Some of their northern populations are migratory, with hummers in North America down to Sonora and Chihuahua in Mexico generally migrating southwards in the winter. However, there are some records of even these northern individuals staying year-round, which may be due to the presence of hummingbird feeders. It seems that there are more and more observations of violet-crowned hummingbirds in North America, suggesting that we are seeing a true range expansion rather than just a few individuals occasionally showing up at the limit of their range.

Is the Violet-crowned Hummingbird Endangered?

No, they are listed by IUCN as Least Concern. They have an estimated population of 2 million, and no threats have been identified; it is a fairly generalist species, both for habitat and food requirements, which makes it somewhat resilient to a lot of human-caused habitat changes. However, especially where it is reliant on riparian habitat, changes to that habitat – such as from droughts, fires, or overgrazing by livestock – can impact food and nest tree availability.

One additional cause of mortality is direct killing by humans, who kill hummingbirds to sell them as love charms. They are usually illegally killed in Mexico and sold in the United States, and it is unclear how many hummingbirds are killed for this trade; violet-crowned hummingbirds represented 5% of the total number of carcasses examined.

Violet-crowned Hummingbird Habits

There is very little information on the song of these hummingbirds, especially on how it is used in social interactions. What we know is that the song that they use while perched is a series of high, thin, descending notes, while their call is a rather dry tak or chap, or a hard chipstik, or tik. They make a wide variety of other calls when interacting with other hummingbirds, including a weep, zeek, tee-eep repeated 3 to 5 times, or a repeated tship or teek.

Though normally not social, there are records of large numbers (dozens to hundreds) of violet-crowned hummingbirds feeding at flowers; whether this was because of a locally abundant but temporary food source, or was involved in breeding displays, is not known. How cool would it be to see hundreds of these flying jewels in one location!

Violet-crowned Hummingbird Predators

Violet Crowned Hummingbirds

The most important predators of hummingbirds are those that find eggs or nestlings, as this is the life stage that is most vulnerable to being eaten by other animals. In fact, predation accounted for 85.7% of nest losses for violet-crowned hummingbirds in one study. Nest predators including jays, orioles, tanagers, and other species (possibly even snakes) will not try to catch adults but will opportunistically consume eggs or defenseless hatchlings. There is even one report of a jumping spider (Paraphidippus cf. aurantius) killing and consuming nestlings – a 10mm spider bit a 40mm nestling until it died.

Whenever hummingbirds use feeders, there is an increased chance of mortality from window strikes and domestic cats. To avoid this, use bird-friendly window markers, place feeders away from windows, and keep cats indoors.

Violet-crowned Hummingbird Lifespan

The oldest violet-crowned hummingbird known was at least 6 years old, but other species of hummingbirds in this size range may live 10 or more years – for most species, we don’t know what the actual maximum lifespan is since hummingbirds are not often banded.

FAQ

Question: Is this species the same as Salvin’s hummingbird?

Answer: No! Salvin’s emerald hummingbird (Cyanthus salvini) is a different species, found in Mexico to Costa Rica. It’s not clear where the name confusion came from.

Question: What is a group of hummingbirds called?

Answer: There are a few different terms for a group of hummingbirds, each more delightful than the last: a glittering, a tune, a charm, a hover, a shimmer, or a bouquet.

Question: Why don’t violet-crowned hummingbirds have colorful throats?

Answer: This is a great question without an answer. We don’t know enough about the basic biology of this species – especially their mating system – to be able to form hypotheses about the evolutionary pressures that selected for the loss of a colorful throat patch. In many hummingbird species, females have less colorful throats than males, suggesting that sexual selection plays a large part in hummingbird throat color.

What’s Next for the Violet-crowned Hummingbird

These hummers will visit feeders, so if you’re in the right area, you may be able to attract one to your yard. However, there’s still not a lot known about the basic biology of this species; most studies were conducted in Arizona, which leaves what they do in the majority of their range still unknown.

The apparent recent range expansion north into Arizona and New Mexico also begs more questions than it answers: have they just been noticed more recently, or is this truly a range expansion? If the latter, then why now?

One idea is that it could be due to the proliferation of non-native flowering plants and feeders that have provided a steady food supply – but then what are the implications of humans causing a species to shift its range?

As someone who has studied ecological and evolutionary questions for decades, I know these are pressing questions; we have altered so much of the landscape that if we wish to continue coexisting with other life, it should be done causing as little additional harm as possible.

Research Citations

  • Baltosser, W. H. (1986). Nesting success and productivity of hummingbirds in southwestern New Mexico and southeastern Arizona. The Wilson Bulletin, 353-367.
  • Baltosser, W. H. (1989). Nectar availability and habitat selection by hummingbirds in Guadalupe Canyon. The Wilson Bulletin, 559-578.
  • Baltosser, W. H. (1996). Nest attentiveness in hummingbirds. The Wilson Bulletin, 228-245.
  • Bruce, M.D.; Stiles, F.G. (2021). The generic nomenclature of the emeralds, Trochilini (Apodiformes: Trochilidae): two replacement generic names required. Zootaxa4950 (2): 377–382.
  • Corcuera, P., & Zavala-Hurtado, J. A. (2006). The influence of vegetation on bird distribution in dry forests and oak woodlands of western Mexico. Revista de biología tropical54(2), 657-672.
  • DeSucre-Medrano, A. E., Gómez del Ángel, S., & Montes Domínguez, H. M. (2016). Notes on nesting of the Violet-crowned Hummingbird (Amazilia violiceps) in a tropical dry forest south of the State of México. Huitzil17(1), 125-129.
  • Domínguez-Laso, M., & Rosas-Espinoza, V. C. (2017). Is the spider Paraphidippus cf. aurantius (Araneae: Salticidae) predator or scavenger of the Violet-crowned Hummingbird (Amazilia violiceps) (Gould, 1859) (Apodiformes: Trochilidae) in Mexico?. Acta zoológica mexicana33(2), 382-385.
  • Jones, L.; Garrett, K.; Small, A. (1981). Checklist of the birds of California. Western Birds12, 57-72.
  • McGuire, J.; Witt, C.; Remsen, J.V.; Corl, A.; Rabosky, D.; Altshuler, D.; Dudley, R. (2014). Molecular phylogenetics and the diversification of hummingbirds. Current Biology24 (8): 910–916.
  • Ornelas, J. F. (2010). Nests, eggs, and young of the Azure-crowned Hummingbird (Amazilia cyanocephala). The Wilson Journal of Ornithology122(3), 592-597.
  • Rodríguez‐Gómez, F., & Ornelas, J. F. (2018). Genetic structuring and secondary contact in the white‐chested Amazilia hummingbird species complex. Journal of Avian Biology49(4), jav-01536.
  • Shackelford, C. E., Lindsay, M. M., & Klym, C. M. (2009). Hummingbirds of Texas: With Their New Mexico and Arizona Ranges. Texas A&M University Press.
  • Stiles, F.G.; Remsen, J.V. Jr.; Mcguire, J.A. (2017). The generic classification of the Trochilini (Aves: Trochilidae): Reconciling taxonomy with phylogeny. Zootaxa4353 (3): 401–424.
  • Trail, P. W. (2022). Dying for love: Illegal international trade in hummingbird love charms. Conservation Science and Practice, e12679.
  • Wetmore, A. (1947). The races of the violet-crowned hummingbird, Amazilia violicepsJournal of the Washington Academy of Sciences37(3), 103-104.
  • Williamson, S. (2001). A field guide to hummingbirds of North America. Houghton Mifflin Harcourt.
  • Zimmerman, D. A., & Levy, S. H. (1960). Violet-crowned hummingbird nesting in Arizona and New Mexico. The Auk77(4), 470-471.

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