Blackbird with white collar ?? is it rare

Question

i have a blackbird in my garden with a pure white collar around the back of his neck it doesnt meet at the front ive never seen one like it before

Kezmo · Accepted Answer

Hi lesno1 
 Welcome to the forum. 
 Must admit have never seen one like that before. Can you post a photo? as it would help others on this site to identify it - are you sure it's a blackbird? Albinoism (sorry if spellng is not correct but it doesn't have a spell checker on here!) is quite common in blackbirds so it could be that.

Buzzard · Answer

Unknown said: 
 
 Just for the record an albino Blackbird would be all over pure white with pink eyes. Albinism doesn't come in degrees. 
 
 
 Or does it......? 
 The specimen Blackbird shown in the RSPB info page has normally pigmented eyes which makes him leucistic in my book. 
 Is there a scientist in the house who can tell us when an albino is really an albino and not just leucistic? 
[/quote] 
 
 Hi JB, hope the following info helps. I have posted this numeous times as they has been several threads relating to birds with white feathers. 
 There has been a lot of literature written on Leucism / Albinism over the last few years, and it really depends on whom you are talking to as to what definition you will be given. 
 There is a difference of opinion and definition of Leucism and Albinism between, "ordinary birders" and scientists. In the scientific circles there seem to be little doubt that the term "albino" is only used if there is a complete lack of pigmentation, including soft parts. Leucism describes the various forms where there is a lack of pigmentation, but not complete. Do note that this lack can be complete in areas and still be considered leucistic, as long as other areas do have pigmentation to some extent. 
 Hence, "partial albino" is not used at all. 
 This also concurs with the ideas taught in the biology classes in university. 
 Scientifically, a bird with white patches is, in fact, Leucistic. 
 However, this is where "ordinary birders" differ, I think in part because the term leucistic only entered the scene fairly recently in these circles. Previously, when not knowing the term leucistic, it would be logical to use the wellknown albino in a modified way; i.e. "partial albino". 
 However, then "leucistic" entered the scene and the confusion appears to be total. 
 Albino refers only to things that have two recessive genes and, therefore, no pigment anywhere. 
 As leucism is a spectrum between white and normal, any odd white feathers are leucistic. This could be genetic, or indeed possibly from infection/trauma and diet may also contribute to abnormalities. 
 If you say 'albino' people think of a pure white bird with pink eyes (no pigment anywhere), and if you say 'leucistic' then most people think of a pale, washed out bird where the colouring is diluted. 
 If you say 'partial albino' then people know what you mean - a bird with white patches. As such, they cannot be 'partial albino' as they do not have both recessive genes. 
 
 Leucism is a condition characterised by reduced pigmentation in animals and humans. Unlike albinism, it is caused by a reduction in all types of skin pigment, not just melanin. 
 
 Leucism is kind of the opposite of melanism. 
 Hope this answers your question. 
 Regards Buzzard