Wednesday, January 22, 2014

Nature Note:Leucistic Bald Eagles

In January,you may find bald eagles on their wintering grounds.Among them may be a rarity,the Leucistic bald eagle.Until the other day,this blog had never heard of the rare colour phase of America's national symbol.A photo came across from Klamath Basin National Wildlife Refuge Complex in Tulelake,California,which is near the Oregon border.It was of a stunning bald eagle,heavily feathered with white.The eagle has been wintering on the refuge for a couple of years now.
Interestingly,an Ann Kisling of Southern Oregon had reported a Leucistic bald eagle at her location in 2010,accompanied by photos.It appeared to this blog that this could be the same eagle that has shown up at Tulelake,California the past few years.Each Leucistic bald eagle has unique plumage,and the photos do show plumage similarity.*
Leucistic bald eagles have a genetic mutation that causes pigment suppression in patches.White is not a colour;it is an absence of pigment.These are birds with white,colourless feather patches.They may present with white wing tips,speckled breasts or heavily flecked breasts.
Leucistic bald eagles are not ill.There is no evidence that they live shorter lives than normal bald eagles.The only possible disadvantage is,they may be mistaken for immature bald eagles during mating season,possibly causing potential mates to avoid them.
What they are is,exceptionally attractive creatures,an example of the endless variety of the natural environment.*
Bald eagle(Haliaeetus leucocephalus)

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