Wednesday, September 21, 2011

Mystery bird: African spotted treecreeper, Salpornis spilonotus

Two other unrelated bird groups have a similar-sounding common name to this Ethiopian mystery bird species
African spotted treecreeper, Salpornis spilonotus (formerly, Salpornis spilonota; protonym, Certhia spilonota), also known as the spotted
creeper, spotted grey/gray creeper, or as the spotted tree creeper, photographed at Wondo Genet, Ethiopia (Africa). [I will identify this bird for you in 48 hours]

Image: Dan Logen, 31 January 2011 (with permission) [velociraptorize].
Nikon D300s, 600 mm lens, ISO 640, f/8, 1/500 sec.

Question: Can you see this Ethiopian mystery bird? If so, can you identify its taxonomic family? Can you identify this species and tell me what makes this species special?

Response: This is a spotted treecreeper, Salpornis spilonotus, a small passerine that is the only member in the taxonomic subfamily, Salpornithinae, within the treecreeper family, Certhiidae. This species is nonmigratory but has a large range consisting of open deciduous woodlands throughout sub-Saharan Africa and into northern India.

The spotted treecreeper is distinct from the other treecreepers in a number of ways: first, it's a large and rather robust bird, weighing as much as twice what any other similarly-sized treecreeper weighs. Second, this species constructs nests and produces eggs are quite different from the Certhiinae species: its nest is an open cup constructed in a crotch of a tree on a horizontal branch, and camouflaged with spiders' egg sacs, caterpillar frass, and lichens. The African population typically produces clutches of three blue or greenish eggs, marked with grey, lavender, and brown whilst Indian birds usually produce clutches of two greenish or grey eggs, spotted darker brown and pale blotches. Unlike other treecreepers, this species has strongly spotted and barred plumage, and it lacks the stiff tail feathers that all the Certhiinae have to support themselves on vertical trees.

Trivia buffs will be interested to learn that there are two other bird groups whose common name includes either "treecreeper" or "creeper": the seven Australasian treecreepers in the family Climacteridae (probably the sister family to the bowerbirds, Ptilonorhynchidae), and the three Philippine creepers in the genus Rhabdornis (a group that is so distinct that they may eventually be placed into their own family).