Identifying crow dieases: Avian pox

Recently, I received an email from someone in distress over an obviously sick crow in their yard. They sent some photos and were wondering about the cause of the crusty areas around the bill and eyes. Although I am by no means an expert in avian diseases, there’s one that’s easy to identify and by far the most common I see in the field so I feel it’s appropriate to provide a brief description of it here.

Bird with a likely avian pox infection as identified by the whitish/pink lesions around the exposed skin.  Photo c/o D. Wright

Bird with a likely avian pox infection as identified by the whitish/pink lesions around the exposed skin. Photo c/o D. Wright

Avian pox is a common disease affecting birds across many different orders including songbirds, raptors and game birds. It’s caused by the avipoxvirus of which there are at least 3 different strains. There’s multiple modes of transmission but it’s most often spread by mosquitoes which is why it’s observed more commonly in the spring and summer months. It can also be spread via direct transmission or indirectly through inhalation of dander, feather debris or sharing contaminated food or water sources (a good reminder to regularly clean feeders and bird baths).

There are two types of avian pox: wet and dry. Wet pox affects the mouth, throat, trachea and lungs and is most likely to be fatal because it can eventually cause suffocation. Dry pox infections are easy to identify because they result in visible lesions and scarring on the non feathered areas of the bird. In the early stages small yellow, white or pink blisters form which become large raised areas that eventually burst. This results in the formation of crusty scabs that, on crows, will appear brown or black. As long as the the bird’s ability to feed isn’t influenced by the location of the scabbing the lesions will generally heal in 2-4 weeks. The general health of the bird before the infection, and the presence of any secondary infections that result from the open lesions will influence the bird’s likelihood of survival.

The pox covered feet of a crow fatally weakened by this disease.

The pox covered feet of a crow fatally weakened by this disease. c/o Sarah Ramirez

If you notice pox infected birds at your feeder(s) the best way to protect your visitors is to stop feeding them. This may seem cruel or counterproductive since sick birds need access to consist food sources to fight the infection, but providing food bonanzas concentrate birds and increases the risk of transmission to healthy individuals. Depending on your situation you may be able to provide food to the individual without worry of creating contact between multiple birds.

Please leave a message in the comments if you have high quality photos of your infected birds and would be willing to let me use them in this post.  Thank you!


Filed under Crow disease, Crow life history

58 responses to “Identifying crow dieases: Avian pox

  1. Pingback: Crowpocalypse 2015 | The Urban Nature Enthusiast

  2. Diana

    Hi , my name is Diana and I live in in Vancouver. I have a family of crows that frequents my back yard and has for years. I have noticed for 3 years in a row that they have only had one baby and that each year it was riddled with the Avian Pox. Nothing on the parents at all….I did feed the baby when I could and the one last year practically fed from my hand……the parents would always look at me curiously when it did that. Despite my best efforts I do believe that none of them survived. I have front yard crows as well…….I was lucky enough to have them build a nest right under my bedroom window in a tree…….I could see the babies being raised which I think is a rare thing. I have a few pictures but they are not very clear.
    I do however have some good ones of the babies with the pox. I also taught the parent to say “Hello” which he does frequently when he wants food. It’s such a shame that so many people think of these birds as a nuisance …I find them fascinating .

    • Jean

      I think one of the crows frequenting my backyard may have pox. I noticed a bump/sore close to its bill. I am glad to have found this site because I was wondering what it might be. It is eating and its feathers are fine but it is very noisy. It often makes motions as if it wants to be fed by other crows. I am sure it is past the fledgling stage. I wonder if it is in distress.

      The other birds are fine – so far. I don’t want to stop feeding them all as we are developing a relationship.

      If a crow survives the initial infection, do I see the lesion etc disappear?

      • Hi Jean, yes you’ll see the lesions scab over and heal with time. It is not unusual, however, to see young begging from parents even into the next years breeding season, provided they don’t disperse.

      • Jean

        I am aware that a past year offspring will hang around into the next breeding season. I have heard that they even help raise the next fledglings. I was not aware that they still wanted feeding. I told my husband that I am sure the crow is saying “Ma, ma, ma” NOT “caw, caw, caw”

        My mission is to have people appreciate crows for the amazing creatures they are. I have won over a lot of converts.

    • Norma

      Me too I called wild life control place near Burnaby lake called deer lake close city hall . Today I found out it’s contageous to other birds and to humans I cought bird then got away wriggled out cloth lol got away I washed my hands e erything I washed. They say no feeding birds but baby birds so cute hey? It’s called pox in feet I’ll try catch him bring him in I have Bum for ride they asked me Catch towel put in box take in right away I’m very upset. I hope crow can get better.

  3. Diana

    how do I submit a photo of a bird with Avian pox?

    • Hi Diana, you can’t submit photos to the website. Are you looking to confirm that a bird has pox?

      • Diana Seear

        No, I am very familiar with the disease, I just have an interesting photo of a bird with pox who ended up dying in my arms… He was on the road and not able to move, I picked him up and was going to take him to a wildlife rehab when I noticed how advanced his pox was. He had only a small one under his eye but large bulbous lesions on the top of his legs. He died as I was getting him into the box.

  4. Marie

    Is there any medication one can give this bird we have that comes to eat every morning. He is not afraid and comes very close to us.

    • Hi Marie, since it’s caused by a virus there’s no remedy you can acquire from a vet or OTC. Main worry with dry pic is secondary infections so just make sure to keep your feeding area clean and try and prevent contact with other birds. Best wishes for a full recovery

  5. Pingback: Have you ever seen a caramel crow?  | Corvid Research

  6. Mirinda

    I have a crow that I absolutely love and adore.. his name is Three toes… I have several photos that I would love to upload and send to see if you can help me diagnose and then tell me what I can do to help him because he’s been around for over a year…. Maybe I can put some medicine in his water or something to help him. I’m on my Android phone and there’s no way to upload any photos here any advice or direction would be greatly appreciated thank you I live in the state of Utah.

    • Hi Mirinda, I’m sorry to hear you have a sick birdo on your hands. My email is I’m not a vet though so unless it’s something pretty common like pox I won’t likely be able to help ID it. I’ll be even less help with treatment other than what I offered on this post. I am happy to keep Three Toes in my thoughts though and send him or her get well vibes. Wish I could do more to help.

  7. ragoorao

    I have a picture of a Large-billed Crow – Corvus macrorhyncus, infected with pox of the feet. How do I share my image with this site. I have pictures of Pipits also suffering from “Warty Feet “

  8. Norma

    Get butterfly catcher but I made mine lol.

  9. Robert

    Other diseases: Cancer? Human childhood diseases? My friends were asking me, and I had never heard of any of these, yet we are both warm blooded.

    • Are you asking if crows get those other things or are you suggesting those other things as diagnoses for the photos? If the latter, I can assure you it’s avian pox, I checked with a couple pathologists.

  10. Jennifer

    Three days ago I encountered a very badly infected crow on the sidewalk at Hastings and Kamloops on the NW corner. The sores on his/her feet were grotesquely large, one with an open wound. Poor baby. He didn’t attempt to get away from me and I considered catching him and taking him to the Wildlife Rescue in Burnaby. At the time I had no idea what I was encountering. In the waitlist to see a doctor at a walk-in clinic, I moved on and then regretted doing so immediately. I bought a croissant for the purpose of coaxing and walked back to try to find him. I did eventually find him with his family on Pender Street between Nanaimo and Kamloops where I spotted three nests in the trees, which I guessed belonged to this group in the breeding season. As they came down one by one to pick up the bits of pastry I tossed to them, I noted that there were at least two more individuals with the same growths on their feet. I had already left a message with the Rescue asking if they were familiar with this type of condition. Yesterday they returned my call and now I know that these crows are suffering from dry, avian pox. It was explained to me that it is nature’s way of keeping Vancouver’s (very healthy) crow population in check. I get it logically, but I still found it emotionally difficult to accept. I’ve become well acquainted with the family of crows in my neighbourhood, whom I feed almost daily. We aren’t far away from the infected neighbourhood, and so I fear for my friends; especially the couple whose babies I’ve been feeding for three years. So glad to hear about all the kindred spirits in my community.

    • Hi Jennifer, it is sad! Best thing you can do is keep everything clean, especially bird baths. Probably not much of an issue now though. So just keep putting good thoughts in the world and let’s hope they heal.

  11. Jennifer

    Also, I wondered, is this strain of avian pox contagious to parrot species? I live with a companion bird and volunteer at a tropical bird sanctuary. Thank-you!

  12. Mark garrard

    I have rescued a baby crow, we have had it for about 2 weeks, it does have a lump uunder its beaks, and recently its voice has softened. Almost lost its voice. Other than that it’s very healthy, feathers look amazing. Jumps around and is learning to fly. Eats none stop. Just wondering if the lump has something to do with it losing its voice.

  13. Dana McCall

    I came across a crow on the side of the road. it was on its belly with wings outstretched and struggling. I stopped and inspected it. It was incapable of standing upright on its own. On its beak ,top and bottom of the same side it had a fleshy growth nearly the size of a walnut! Is this also pox?

  14. I am an avid crow watcher who lives near Seward Park. I have noticed that about 80% of the crows seem to have extremely bedraggled plumage, and appear to be shedding (almost to bald) behind their heads/shoulder area. Is there something infectious that has overtaken the flocks? also, I have seen many mentions of the north seattle roosts, but never of this one where they end up in Tukwila. thank you, mark

  15. Laura

    Hi there I have video of one of my crows with oox on her feet and another picture of a crow growing pox around his eye.

  16. Laura Ansley

    I have a question. It says 2 to 4 weeks before dry pox can heal but my crow has had it for well over 6 weeks now on her feet and the one pox ball keeps getting bigger. Why is it growing when I thought it should be gone or at the very least healing?
    She is eating and doing crow things but her 1 foot is becoming more and more uncomfortable for her and she usually has it raised when she is resting. Then you can see how uncomfortable she is.

    • I’m not sure Laura. How’s it looking now?

      • Laura

        I believe she died approximately a week and a half ago. She came for a visit late, after the rest of the crows went to roost, hung out for a bit, floofed up and resting by the water bucket. She for the first time I witnessed, was pulling chunks off her big pox on her back talon. I saw her fly to a tree close by and that was the last I saw her. I was hoping as I was away for a few days after that that I would see her but I haven’t. I was then wondering if she had picked it all off both feet so I have been checking out some of the feet on the crows that visit but it is a long shot. It is such a sad situation.

      • Laura

        Thanks. It certainly didn’t follow the regular route that research indicated.

  17. Ann Thomasson Parker

    I have what I suspect to be a junvenile crow in my backyard who is exhibiting many of the symptoms listed above. I think, however, that it has wet pox as it has what appears to be a large growth in its mouth, almost the size of a grub worm. It can drink from my water bowls, and it still has its parents feeding it. Will this type of pox ever go away? I read that it likely will cause suffocation, so I am not surprised by the size of the growth in its mouth.

    • Hi Ann, I’m really not sure. Avian pathology is not my area of expertise. All I can offer is to make sure to keep water sources extremely clean though so that it doesn’t get spread to anyone else.

  18. Andrea

    Hi, i found a baby crow in my backyard, but i decided to leave it alone and not touch it as its parents seemed to be nearby and looking after it. But recently, when i checked up on it, i saw that it didn’t seem to be doing that well and it had some kind of crusty formation on the side of its beak and on one eye. one eye was completely closed up , while the other was almost closed up, there was just a small hole through which i think it can see me. I tried giving it some water and it reacted well, by opening its beak wide and drinking, but i don’t know what to do about the crusty formation. PLEASE HELP! I really don’t want this crow to die at such a young age!

    • Hi Andrea, unfortunately there’s very little you can do for an animal like this with a veterinary and rehab background. Most rehab places will just euthanize on site for a case like this. There’s nothing you can do but hope for the best. I think your compassion for this bird is lovely though.

  19. Tim

    Can you use Baytril on a crow

  20. Thank you so much for providing useful information…

  21. janeysgotagun707

    I have a couple of really good ones I can share that you can use . I can try to send them asap if you have a way to get the photos via email?

  22. I have treated crows for pox if photos are required.

  23. I found a crow on the ground and picked it up thankfully I have a black shirt and hand sanitizer. The crows feet are very huge and white dry no moisture. The wings are hurt too. Idk what to do with it.

  24. My photo of an afflicted raven spotted yesterday at Scafe Hill, south Vancouver Island:

  25. G

    I know this is a very old post so not sure if still checking. I have a crow that regularly visits my yard that has knobby bald white ankles. His feet and the rest of his legs and body look fine and he seems healthy. The only reason I am concerned is that the other crows all are feathered here to some degree but his are bright white and stand out. I have (many) videos of him. Should I be concerned this is pox and stop feeding to avoid spread?

    • Hi G, that does sound like pox, albeit maybe a case on the mend. I would avoid mixing this bird with others as possible.

      • Michelle

        Hiya, I have a crow at work that I feed and it seems to have lost all its tail feathers and some wing ones too. It doesn’t seem to be able to fly well. Just up on to the picnic benches etc. I have a few photos. Just wondering if there’s any I could do to help him/her?

      • Hi Michelle, the feathers will grow back within the next couple months because it’s molting season. For any bird molting season is a vulnerable time and I hope your fella makes it!

      • Laura Ansley

        When I was out feeding crows the other day at a park I noticed one crow who looked like he had been plucked from top to bottom on his underside. It was weird. He looked like those stressed parrots on his belly and chin. Since it’s also molting season here do you think he may grow his feathers back? Is this a disease as well?

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s