Sunday, 28 June 2015

Red-spotted Bluethroats

An adult male red-spotted Bluethroat Luscinia svecica 

One of the more abundant passerines in northern Norway is the red-spotted Bluethroat, a robin-like bird that lives in birch and willow scrub, foraging for insects on the ground, while flicking from bush to bush. It is usually their tinkling song, or clicking contact call that gives away their presence, or thiier distinctive short flight low through the scrub.

An adult female red-spotted Bluethroat 

Most illustrations are of the brightly coloured males as they do have splendid throat colouring.  So I have added an image here of a female in breeding plumage. She has the basic colouring of the males, but duller and she has a darker, streaked breast than the males. This is because she needs to be less conspicuous while caring for her eggs and young.

Although conspicuous when singing from the top of a bush with their breast puffed up, most of the time, even male Bluethroats are secretive, passing quietly through the lower branches, dipping between shadows.

The intensity of the throat colouring varies between males and females, not all are bright, and the pattern varies in the amount of red in the spot, blue on the throat, or black, white and red on the lower bands. And I wonder how the birds see these colours, for the blue feathers have a shine to them, do the birds see an even brighter image via ultra-violet light sensitive visual perception?

The blue feathers on their throat, glisten in the sunshine, adding a marvellous metallic tint to the birds' plumage

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