Posted by Gaurav Manglik on February 7, 2010 at 11:22 PM
Photographed this little fella at Shoreline Park in Mountain View, California today.
a) I am not sure about Id. Looks like a white-crowned juvenile too me.
b) the right claw/foot is swollen and is diseased. Any ideas or information on this ? Has this been seen before ? Could it be because of some environmental pollutant ?
Posted by Drew Fulton on February 8, 2010 at 12:51 AM
Guarav,
I am less familiar with Western sparrows and don't have a field guide handy but I agree with your ID. Juvenile White-crowned is my first instinct.
I can't comment on the toe much. To me, it looks like an infection but other than that I know nothing. Maybe someone can chime in who knows more about immunology.
Drew
Posted by David Graham on February 8, 2010 at 1:30 AM
Gaurav,
Many such lesions of the skin of the foot, the non-feathered tarso-metatarsus and naked or sparsely feathered regions of the head/face of many species of birds, if subjected to competent diagnostic procedures (biopsy, histopathological examination,and virus isolation / electron microscopy/PCR ) will be shown to be the result of infection with avipoxvirus. If the lesions are numerous and of extensive distribution the bird will likely succumb to the effects of secondary bacterial infections when the overlying skin of the pox lesions ulcerate. If the lesions are small and of scant distribution the bird may survive and be, thereafter, immune to re-infection. This external epidermal poxvirus infection is termed "dry pox". In some individuals the lesions may spread to, or may originate in and be limited to the lining of the mouth, upper digestive tract and upper respiratory tract. This internal form is termed "wet pox" and recovery therefrom is extremely rare.
I notice the open beak and elevation of the tongue. This could, of course, be a momentary position of beak during vocalization lasting but an instant. But if it were a more enduring deformity, I'd have to be concerned about the possibility of oral poxvirus infection or some other oral lesion.
I should also, in all candor, state that a localized bacterial infection of the skin and/or of one of the joints of the toe could also appear grossly similar to the lesion of the toe of the pictured sparrow.
I'd bet on pox. The avipoxvirus is unable to penetrate the unbroken skin and relies on mosquitoes or other biting insects to transmit the infection. Incidental skin injuries can also become infected from contact with the virus on environmental surfaces that bear virus contamination from lesions of other birds... perhaps at bird feeders or birdbaths?
Birders who conscientiously maintain bird feeders should just as conscientiously observe the birds for evidence of illness and note any deaths in the vicinity of the feeders / birdbaths. Your State Veterinary Diagnostic Laboratory , or Poultry Diagnostic Laboratory (in California that's at U.of C. at Davis) should be notified if there are objective reasons for concern about the health of the birds at feeding stations.
David L. Graham (D.V.M., Ph.D., Diplomate of the American College of Veterinary Pathologists, and retired wildlife disease researcher and diagnostic pathologist .... and avid photographer)
Posted by Brian Gatlin on February 8, 2010 at 8:32 AM
thanks a lot for the replies. Thanks a lot for the details David.
could, of course, be a momentary position of beak during vocalization lasting but an instant
This is indeed a momentary position. Hard to tell at this size but the beak has a little piece of twig or straw in it which the bird is nibbling on.
Birders who conscientiously maintain bird feeders should just as conscientiously observe the birds for evidence of illness and note any deaths in the vicinity of the feeders / birdbaths
This is not at a feeder. These are wild birds in a completely wild setting (shoreline marsh area in Mountain View).
I would now look out for other sparrows at this location and see if they have the same swelling. It might be a good idea to notify somebody regardng this - not sure who ?
David, wow, what a bunch of great info!
I'm always amazed at the wealth of knowledge on this site!
Sandy r
Posted by David Graham on February 8, 2010 at 2:46 PM
Gaurav,
You wrote:
"I would now look out for other sparrows at this location and see if they have the same swelling. It might be a good idea to notify somebody regarding this - not sure who ? "
If you do wish to follow up on this I'd suggest that you call the College of Veterinary Medicine at U.C,Davis and ask for Dr, Hulumungula Asicoti Lingaredi Shiva Prasad in the Poultry Disease Diagnostic Lab... (who, luckily, goes comfortably by, and answers readily to "Dr. Prasad"). He is likely the person most up-to-date on the occurrence of diseases among wild birds in California. If he's not at U.C.Davis, they surely can let you know where to find him.
And when you reach him, give him my best regards. We taught together at Cornell and he and his wife treated me to a most wonderful home-cooked Indian meal when we both lived in Ithaca.
Discussion
8 repliesa) I am not sure about Id. Looks like a white-crowned juvenile too me.
b) the right claw/foot is swollen and is diseased. Any ideas or information on this ? Has this been seen before ? Could it be because of some environmental pollutant ?
I am less familiar with Western sparrows and don't have a field guide handy but I agree with your ID. Juvenile White-crowned is my first instinct.
I can't comment on the toe much. To me, it looks like an infection but other than that I know nothing. Maybe someone can chime in who knows more about immunology.
Drew
Many such lesions of the skin of the foot, the non-feathered tarso-metatarsus and naked or sparsely feathered regions of the head/face of many species of birds, if subjected to competent diagnostic procedures (biopsy, histopathological examination,and virus isolation / electron microscopy/PCR ) will be shown to be the result of infection with avipoxvirus. If the lesions are numerous and of extensive distribution the bird will likely succumb to the effects of secondary bacterial infections when the overlying skin of the pox lesions ulcerate. If the lesions are small and of scant distribution the bird may survive and be, thereafter, immune to re-infection. This external epidermal poxvirus infection is termed "dry pox". In some individuals the lesions may spread to, or may originate in and be limited to the lining of the mouth, upper digestive tract and upper respiratory tract. This internal form is termed "wet pox" and recovery therefrom is extremely rare.
I notice the open beak and elevation of the tongue. This could, of course, be a momentary position of beak during vocalization lasting but an instant. But if it were a more enduring deformity, I'd have to be concerned about the possibility of oral poxvirus infection or some other oral lesion.
I should also, in all candor, state that a localized bacterial infection of the skin and/or of one of the joints of the toe could also appear grossly similar to the lesion of the toe of the pictured sparrow.
I'd bet on pox. The avipoxvirus is unable to penetrate the unbroken skin and relies on mosquitoes or other biting insects to transmit the infection. Incidental skin injuries can also become infected from contact with the virus on environmental surfaces that bear virus contamination from lesions of other birds... perhaps at bird feeders or birdbaths?
Birders who conscientiously maintain bird feeders should just as conscientiously observe the birds for evidence of illness and note any deaths in the vicinity of the feeders / birdbaths. Your State Veterinary Diagnostic Laboratory , or Poultry Diagnostic Laboratory (in California that's at U.of C. at Davis) should be notified if there are objective reasons for concern about the health of the birds at feeding stations.
David L. Graham (D.V.M., Ph.D., Diplomate of the American College of Veterinary Pathologists, and retired wildlife disease researcher and diagnostic pathologist .... and avid photographer)
This is indeed a momentary position. Hard to tell at this size but the beak has a little piece of twig or straw in it which the bird is nibbling on.
This is not at a feeder. These are wild birds in a completely wild setting (shoreline marsh area in Mountain View).
I would now look out for other sparrows at this location and see if they have the same swelling. It might be a good idea to notify somebody regardng this - not sure who ?
I'm always amazed at the wealth of knowledge on this site!
Sandy r
You wrote:
"I would now look out for other sparrows at this location and see if they have the same swelling. It might be a good idea to notify somebody regarding this - not sure who ? "
If you do wish to follow up on this I'd suggest that you call the College of Veterinary Medicine at U.C,Davis and ask for Dr, Hulumungula Asicoti Lingaredi Shiva Prasad in the Poultry Disease Diagnostic Lab... (who, luckily, goes comfortably by, and answers readily to "Dr. Prasad"). He is likely the person most up-to-date on the occurrence of diseases among wild birds in California. If he's not at U.C.Davis, they surely can let you know where to find him.
And when you reach him, give him my best regards. We taught together at Cornell and he and his wife treated me to a most wonderful home-cooked Indian meal when we both lived in Ithaca.
David Graham