Unique Beauty: A Leucistic Black Phoebe
While other Americans were out spending billions of dollars shopping on Black Friday, Eric and I spent a beautiful day birding leisurely around two of my favorite local "hotspots": San Luis and Merced National Wildlife Refuges. And what an exciting day we had! To top off our list of nearly 60 species of birds, we saw a couple of real stunners: one rarity - a leucistic Black Phoebe - and one thrilling lifer that took my breath away and left me literally shaking with excitement! (More to come on that exciting bird very soon!!)
Credit for originally finding this leucistic Black Phoebe goes to fellow birder and blogger, Garry Hayes, who spotted this bird (I assume it's the same bird!) about a month ago and wrote about it on his blog, Geotripper's California Birds. I thought the unique white Black Phoebe was really neat when he shared the pictures with me last month, but since several weeks had passed, I'd actually completely forgotten about it!
Yesterday, as we were driving along Merced NWR's auto tour route, which loops around a wetland favored by tens of thousands of geese, ducks and cranes every winter, I suddenly spotted something unusual in the cockleburs along the road. I recognized the oddly colored little bird immediately, and exclaimed, "Look! It's Garry Hayes's leucistic Black Phoebe!" (Anyone other than my wonderful husband would have thought I was nuts, I'm sure!)
We watched this bird for quite a while, entranced by its unique beauty and typically lively flycatcher personality. I've never seen another bird that looks anything like this and I think perhaps if this bird was its own species, it might become my favorite local species!
Most (if not all?) of the white birds found in Central California are large and spend a great deal of their time on or near water: geese, swans, pelicans, gulls, and egrets. Other white birds are found in snowy climes: Snowy Owls, Snow Buntings, ptarmigans, etc. And you can bet there is a perfect reason for the coloration of each of these species! (For example, it is supposed that the striking white color of egrets hides them from their prey, rather than their predators, since their prey is often in shallow water, looking up into a sunny sky where the long neck of an egret might be mistaken for just another ray of brilliant sunlight.) Small birds are not often white, as white is the brightest, most obvious color in nature, attracting the notice of predators. You might be surprised how well even brightly colored yellow, red and blue birds blend into foliage. But white birds stand out!
So, you're probably wondering, what exactly does "leucistic" mean, and why is this bird not considered "albino" instead? Albinism, leucism and melanism are all relatively harmless genetic mutations effecting an animal's pigmentation. Albino animals lack pigment altogether, and are entirely white or pinkish white, with red eyes (since they lack pigment in their irises that would otherwise hide red-colored blood vessels).
More common in birds than in other animals, leucism is only a partial lack of pigment. More specifically, the genetic mutation prevents pigment, particularly black or brown colored melanin, from being properly distributed throughout a bird's feathers, resulting in a "partially albino" look. As you can see from this Black Phoebe, leucistic birds have dark or normal colored eyes and still retain some pigment in their feathers.
Melanistic animals, on the other hand, produce an excess of the pigment melanin, making them look all black or dark brown. (Do a Google search of melanistic animals: there are some real beauties out there!)
Other more rare cases of altered pigmentation include erythrism, an excess of reddish pigmentation, and xanthism, an excess of yellow pigment, which is what appears to be going on with the famous yellow cardinal. (It seems yellow coloration can also be caused by diet in some animals, like House Finches that are yellow or orange instead of red.)
And in case you've spent this entire time wondering what exactly a normal Black Phoebe looks like... here it is!
Credit for originally finding this leucistic Black Phoebe goes to fellow birder and blogger, Garry Hayes, who spotted this bird (I assume it's the same bird!) about a month ago and wrote about it on his blog, Geotripper's California Birds. I thought the unique white Black Phoebe was really neat when he shared the pictures with me last month, but since several weeks had passed, I'd actually completely forgotten about it!
Yesterday, as we were driving along Merced NWR's auto tour route, which loops around a wetland favored by tens of thousands of geese, ducks and cranes every winter, I suddenly spotted something unusual in the cockleburs along the road. I recognized the oddly colored little bird immediately, and exclaimed, "Look! It's Garry Hayes's leucistic Black Phoebe!" (Anyone other than my wonderful husband would have thought I was nuts, I'm sure!)
We watched this bird for quite a while, entranced by its unique beauty and typically lively flycatcher personality. I've never seen another bird that looks anything like this and I think perhaps if this bird was its own species, it might become my favorite local species!
Most (if not all?) of the white birds found in Central California are large and spend a great deal of their time on or near water: geese, swans, pelicans, gulls, and egrets. Other white birds are found in snowy climes: Snowy Owls, Snow Buntings, ptarmigans, etc. And you can bet there is a perfect reason for the coloration of each of these species! (For example, it is supposed that the striking white color of egrets hides them from their prey, rather than their predators, since their prey is often in shallow water, looking up into a sunny sky where the long neck of an egret might be mistaken for just another ray of brilliant sunlight.) Small birds are not often white, as white is the brightest, most obvious color in nature, attracting the notice of predators. You might be surprised how well even brightly colored yellow, red and blue birds blend into foliage. But white birds stand out!
So, you're probably wondering, what exactly does "leucistic" mean, and why is this bird not considered "albino" instead? Albinism, leucism and melanism are all relatively harmless genetic mutations effecting an animal's pigmentation. Albino animals lack pigment altogether, and are entirely white or pinkish white, with red eyes (since they lack pigment in their irises that would otherwise hide red-colored blood vessels).
More common in birds than in other animals, leucism is only a partial lack of pigment. More specifically, the genetic mutation prevents pigment, particularly black or brown colored melanin, from being properly distributed throughout a bird's feathers, resulting in a "partially albino" look. As you can see from this Black Phoebe, leucistic birds have dark or normal colored eyes and still retain some pigment in their feathers.
Melanistic animals, on the other hand, produce an excess of the pigment melanin, making them look all black or dark brown. (Do a Google search of melanistic animals: there are some real beauties out there!)
Other more rare cases of altered pigmentation include erythrism, an excess of reddish pigmentation, and xanthism, an excess of yellow pigment, which is what appears to be going on with the famous yellow cardinal. (It seems yellow coloration can also be caused by diet in some animals, like House Finches that are yellow or orange instead of red.)
And in case you've spent this entire time wondering what exactly a normal Black Phoebe looks like... here it is!
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