This wide-ranging research project focuses on hummingbirds in BC and Alberta.
There are 338 species of hummingbirds. They are found in North and South America only.
In BC, we see five species of hummingbird regularly. The Rufous (Selasphorus rufus), Anna's (Calypte anna), Calliope (Selasphorus calliope) & Black-chinned (Archilochus alexandri) occur primarily on the west side of the Rockies, while the Ruby-throated (Archilochus colubris) occurs to the east.
On South Vancouver Island and the coast, we see Rufous and Anna's hummingbirds at our feeders. Rufous are only here during the spring and summer, as they spend their winters on the U.S. Gulf coast and in Mexico. Although an unusual sight twenty years ago, Anna's are now winter regulars at many Victoria feeders. Do not worry! Feeders will not stop a bird migrating, a process that is triggered by the bird's internal clock and levels of sunshine. Anna's are with us year-round and their presence at feeders has just become more obvious because their numbers are increasing locally.
In the interior, Rufous, Calliope and Black-chinned Hummingbirds are common in spring and summer. They migrate up form Mexico to breed in BC. Anna's Hummingbirds are becoming much more common too. There are a few hardy winter residents, but most will be seen in mid to late summer, having migrated from the coast.
Rufous vs Anna's
First of all, the Anna's are considerably larger than the Rufous. Distinguishing the males is easy. They have shiny metallic feathers around their throat, called a gorget. In Rufous, these feathers are orangey-red. In Anna's, the gorget is a fuchsia purple/pink. In addition, Anna's males have shiny feathers on the tops of their heads. The Rufous males also have a reddish wash to the belly and often, a completely red back, whereas Anna's males are green. The females are a bit more difficult. Female and juvenile Anna's and Rufous hummingbirds will have white tips on their outer tail feathers. The females have a central patch (sometimes with only a few) of metallic gorget feathers of the same colours as the males. The female Rufus will have a reddish wash along the sides, whereas the Anna's sides will be green/grey - they have no reddish colouring.
The Calliope is our smallest hummingbird. Adult males are notable for their magenta gorget, which forms a spray that can be raised during display to look like a star (hence its previous scientific name, Stellula calliope). Their close relationship to the Rufous has led to reclassification as Selasphorus calliope. While the adult females of Calliope and Rufous Hummingbirds are different sizes, they look similar, with green backs and rufous washes along the sides. Pay close attention to tail length when they are sitting – the Calliope's wing is longer than its tail, while the Rufous tail extends well past the wing!
The Black-chinned Hummingbird male has a dark face and a mostly black gorget with a purple bib. Both sexes have a green back and white breasts, with some green on the sides. The female has a white throat and white tips on the outer tail feathers.
These birds are found east of the Rockies. Both sexes have green backs and white breasts. The male has a ruby-red gorget, black chin and forked tail. The female has a white throat and notched tail, with white tips to the outer tail feathers.
Hummingbird nests are small and cup-shaped. You may see hummingbirds collecting spider silk and which is used to hold soft nest material so that the nest can stretch and grow with the young birds. The outside of the nest is decorated with lichen, to make it hard for a predator (or hummingbird enthusiast) to spot.
Hummingbirds lay 2 eggs per clutch. Occasionally a third egg has been seen in a nest, but these are probably unhatched eggs from a previous clutch. The female does all the work, nest building and raising the young. Eggs can be lost to predation by small mammals or other birds. The eggs take about 2 weeks to hatch, and the young fledge in another 2 weeks. Monitoring allows us to learn when certain life stages occur, such as egg laying and hatching.
The timing of breeding is different according to species and area of BC. Our resident Anna's Hummingbirds breed earlier than the migratory species that come here from Mexico. The Anna's are one of the earliest birds to breed (along with the Great Horned Owl), starting in late December or the beginning of January. They may lay a number of clutches consecutively and their primary breeding period is January through May, but is not restricted to that time frame. On the south coast of BC, Rufous start to arrive in late March/early April and will usually have one or two clutches. Breeding can continue into late May/early June. In the interior, where spring comes later, Rufous, Black-chinned and Calliope Hummingbirds arrive in May. Their season is similarly offset from the coast. There is some indication of Anna's breeding in the interior and their timing is similar to the migratory species.
The shiny metallic colours we see on hummingbirds are actually produced by structure rather than pigment. Think about an orange-coloured carrot – it looks the same colour all the time. That is because it uses pigment. In contrast, an oil sheen can have many colours because light waves are being shifted by structure. The shiny feathers on hummingbirds are like an oil slick, and that is why they can look black from many angles. Black is the absence of light.
When light intercepts the feather, it bounces back and the reflected light is what we see.
However, because these feathers have many thin layers, light can penetrate different layers before being reflected. The layers of the feather barb contain platelets with tiny sacs of air, which cause different amounts of bending (refraction) of light. Depending upon the angle of light entering the feather, and the additive effects of light waves coming back from different layers, what we see will range from bright iridescence or no colour at all (black).
You can see the range of observed colours on this Anna's and see more in our Anna's iridescence video.