Society Finch drinking copious amounts of water

Question
Hi.  Any advice you can give would be most appreciated.  I have 4 society finches (all approx. 4.5 yrs. of age).  Two males / 2 females.  One of my males has lost his feathers around one ear and onto his neck (and they have not grown back - there is no pecking from other birds and I do not see him pulling them) and I've observed him drinking more and more water to the point of draining TWO water feeders per day!  I'm thinking it must be a systemic issue that drives him to drink so much water.  Taking him to my vet would be too traumatic as they are not tame birds.  Any advice as to what this may be stemming from?
Thank you!
Ana

Answer
Sounds like he's sick with something. A vet trip would help but if you are worried, buying some liquid iodine from the website provided may help. This will should also help his feathers grow back. Iodine everyday for approximately one to two weeks should help. Also, a heater from the reptile section at the pet store kept around 30C will do wonders.