Monday, September 19, 2011

Sipping the sun

Scarlet-chested Sunbird, Chalcomitra senegalensis (male), at Agahozo-
Shalom Youth Village, Rwanda

Sunbirds are little gems that will catch your eye. Bright reds, greens, blues, and then woah, is that the same bird? Where did its color go? What just happened? Male sunbirds seem to change color as they move around. The males of many sunbird species have iridescent feathers, which reflect light differently depending on how light hits them. 

Bronzy Sunbird, Nectarinia kilimensis (male),  at Agahozo-Shalom Youth
Village, Rwanda

Sunbirds and hummingbirds are similar but they are not related. They fill the same niche in that they find flowers and sip nectar. In my experience, hummingbirds are considerably faster and buzz around, blurring their wings; sunbirds are much slower, perch when they sip, and appear much like any other bird in flight.

Bronzy Sunbird, Nectarinia kilimensis (female) at Gisenyi, Rwanda

Like hummingbirds, most sunbird males are different than sunbird females (sexual dimorphism). Most would describe the males as beautiful and the females as dull. The males are certainly more colorful, but I like to remind people the females do the choosing, so the pretty boys are at the mercy of the females.

This is a fun picture, but a tricky ID. This is either a female Bronzy Sunbird
or a female Marico Sunbird, feeding a moth to a youngster. The females of
each species are incredibly similar in size, plumage, and field marks. Taken
at Agahozo-Shalom Youth Village, Rwanda, where both birds are common.

Marico Sunbird, Cinnyris mariquensis (male) at Agahozo-Shalom
Youth Village, Rwanda

An endemic bird is generally a treat for any birder because endemism means that a species is only found in a certain area or habitat in one part of the world. Several of these birds, like the Regal Sunbird, the Blue-headed Sunbird, and the Purple-breasted Sunbird, are only found (endemic) in the forests of the mountains along the Albertine Rift in central Africa (sorry, no pictures yet). Others, like the Green-Headed Sunbird and the Red-chested Sunbird are endemic to the East Africa region (pictured below). Still others, like the Amani Sunbird and the Banded Green Sunbird, are endemic to tiny little patches of forest that top mountains in eastern Tanzania (no pictures). Endemism occurs because species evolve over time to fit new environmental opportunities. Some endemic species are very similar to other species in other habitats or regions while others have adapted to be quite unique. 

Red-chested SunbirdCinnyris erythrocerus (adult male) in Gisenyi,

Michele and I have seen 30 species of sunbirds between Rwanda, Tanzania, and Uganda. I did not really succeed in photographing them outside of Agahozo and one other location in Rwanda. Sunbirds are generally active and snapping a picture takes a fast camera or a lot of patience. Only with the Usambara Double-collared Sunbird and the Blue-throated Brown Sunbird did we get lucky. All of the other pictures shown here took considerable time and are what I consider the best of hundreds of shots. 

A female Red-chested Sunbird? Nope! This one is a juvenile male in
Gisenyi, Rwanda.

We have seen the following sunbird species in Africa: Golden-winged Sunbird, Bronzy Sunbird, Purple-breasted Sunbird, Blue-headed Sunbird, Blue-throated Brown Sunbird, Green-headed Sunbird, Malachite Sunbird, Olive-bellied Sunbird, Eastern Double-collared Sunbird, Usambara Double-collared Sunbird, Northern Double-collared Sunbird, Rwenzori Double-collared Sunbird, Regal Sunbird, Banded Green Sunbird, Amethyst Sunbird, Little Green Sunbird, Copper Sunbird, Superb Sunbird, Olive Sunbird, Purple-banded Sunbird, Marico Sunbird, Hunter's Sunbird, Scarlet-chested Sunbird, Red-chested Sunbird, Beautiful Sunbird, Variable Sunbird, Collared Sunbird, Amani Sunbird, Uluguru Violet-backed Sunbird, Eastern Violet-backed Sunbird.

Usambara Double-collared Sunbird, Cinnyris usambaricus (male), in the
West Usambara Mountains, Tanzania. This bird is endemic to
the West Usambara Mountains, but it has only recently been considered a
separate species from the Eastern Double-collared Sunbird. 

All of the sunbirds, bright and dull, have their charm as they cruise from flower to flower, inserting their bills to extract nectar or snatch an insect. So sit back, take a sip of the sun, and enjoy the colors!

Green-headed Sunbird,  Cyanomitra verticalis (male) in Gisenyi, Rwanda

Blue-throated Brown Sunbird, Cyanomitra cyanolaema (male) at Mabira
Forest, Uganda

Variable SunbirdCinnyris venustus (female) at Agahozo-Shalom Youth
Village, Rwanda

Variable Sunbird, Cinnyris venustus (male) at Agahozo-Shalom Youth
Village, Rwanda

Works Consulted
  • Fanshawe, J. and Stevenson, T. Birds of East Africa. Princeton and Oxford: Princeton University Press, 2002.
  • Pearson, D.J., Turner, A.T. and Zimmerman, D.A. Birds of Kenya & Northern Tanzania. Christopher Helm: London, 1999.
  • Roberson, D. "Sunbirds: Nectariniidae" 1999. Bird Families of the World. Accessed 19 September 2011.
  • Ryan, P. and Sinclair, I. Birds of Africa south of the Sahara. Struik Nature: Cape Town, 2003

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