I know normally you don't see a bird's ears because they are covered with feathers. However, for about the last week or so I have been able to see my tiel's right ear. Is that okay? Could it just be a molting issue?
Unless there is another bird that could be plucking him it is a molting issue. Birds cannot pluck their own heads. If you don't see improvement in a month, take him in to see if there is something else going on.
Owned by birds since 1988. Cockatiels Tweety - DOH June 1988 Ash - DOH around 1999 Unix - DOH around 1996 IRN Princess Buttercup - DOH 2000 4 Lady Gouldian Finches (Lil Red, Houdini, O'Neill, Teal'c DOH 2003) Slave to 8 birds. See them here.