Finches can be plagued by feather, skin or leg mites. Symptoms involve roughened skin or legs and irritated movements, shaking and scratching. Mites can be microscopic or visible if they are feather mites. Birds can also present with air sac mites, which live inside the bird. Mites are a type of arachnid that are related to ticks. The bird mites are able to leave the host, so eradicating them from the bird's environment is necessary to stop an infestation. Consult an avian veterinarian for treatment.
Air Sac Mites
Air sac mites live in the bird's air sacs. They can be transmitted to other birds and do live for short periods outside the bird on roosts or other objects. These rare mites are as tiny as black salt grains and can be seen in the mouth of the finch. Birds may exhibit a drooping tail or have difficult breathing. This mite needs to be treated by a veterinarian who will usually prescribe anthelmintics.
Skin or Face Mites
These microscopic mites burrow in the face, beak and legs of the bird. They can cause disfigurement, though temporary, and are diagnosed by outward symptoms and a skin scraping. The earliest signs of this slow-spreading issue are a whitish residue, swelling or thickening of skin on the face or raised and thickened scales on the legs. These mites are treated with anthelminthics dosed by a veterinarian.
These tiny, sand grain-sized mites are on the body of the bird and feed on the bird's blood. They can cause anemia, so it is advisable to have a veterinarian rule this complication out. Treatment for light infestations can be done by dusting the bird with food-grade diatomaceous earth, or follow the directions on a proprietary pet bird or poultry insecticide dust or spray. The bird's cage and objects must be washed. Treat the roosting area with the insecticide.
Leg mites are similar to the face mites in that they burrow under the scales of the feet. The thickened crusty scales may be raised and eventually fall off. These mites are treated by soaking the feet in an ivermectin solution and then repeating the process in one week, or by applying petroleum jelly to the feet. Use the petroleum jelly every three days for two weeks.