This little guy came to us because he flew onto someone's porch and landed on them. He was not behaving normally, and they knew something was wrong and brought him to us. Sadly, this is likely a case of improper (and illegal) rehabilitation. This finch is imprinted on people, and based on his behavior we suspect someone found him orphaned and tried to care for him at home. We try to explain to people that this is never in the best interest of the animal. Having not been around other finches - he is very confused.
He wants people to respond to him like a mate would respond, and then gets frustrated and tries to nip and bite. He also was not fed appropriately and lacks some pigments to his feathers - this can be corrected. It remains to be seen if the behavior he is exhibiting can be corrected. There is also permanent deformity to one toe, but he perches well so that is not a significant issue - but, it could have been caused by improper caging or diet.
It is too soon to determine what will happen. He likely was raised and then released, and then did not know what to do nor where to go. We can try to see if he will "wild up" or we can possibly look at placement in an educational facility.
PLEASE, leave wildlife rehabilitation to the rehabbers and facilities that are licensed to care for these animals. There are MANY steps in the process besides just offering food and water and releasing. Status - transferred. This bird was sent to another facility in the hopes it could be put with other of his species to become releasable.