Thank you for your question.

The signs you are describing are very suspicious of head trauma in this bird since he has what sounds like acute balance issues with normal leg function and an absence of visible external injury. We cannot rule out bacterial brain disease, but chronic issues in wild animals tend to impede survival and these animals are often quickly caught by predators. As well, there is intoxication but we'd likely see progressive signs instead of static. And in this case, you want to get him to someone who will be able to provide the treatment he requires (and some bird safe anti-inflammatories can help relieve brain swelling if present).

To get him help, you can contact your local bird rehabilitation center. You can check the Wildlife International (LINK), US Wildlife Rehabilitation (LINK), Wildlife Rehabbers (LINK), or Wildlife Sanctuaries (LINK) databases to find a rehabilitation agency are near by. These rehabilitators will be best prepared to care for this bird and also will have the permits required to care for wildlife (since in some states it is against the law to keep wild birds in captivity without a permit). As well, they will be about to ID his exact species, since diet requirement vary dramatically between the species, and we don't want to have a nutritional imbalance on top of things.

Alternatively, you can turn this bird over to your local veterinary practice and they will be able to examine/treat him and be able to directly turn him over to the rehabilitation centre (often the vets will have a relationship with the local rehab centre and sometimes are able to get them in even if the facility isn't accepting birds from the public).

Overall, the best thing you can do with a head trauma case is to have a vet check his neurological function and treat with anti-inflammatories and supportive care during this period of injury/shock. Therefore, it would be worth considering having a vet evaluate and take over the care of this wee bird or turning him over to the rehabilitation center so they can take him in to their avian vet. This will give him a chance to receiving the care he needs and give him the best chance of survival.

I hope this information is helpful.
Please do let me know if you have any further questions.
If you have no further questions, feedback is always appreciated.

All the best,

Dr. B.

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