I'm pretty sure this is the typo :o)

FreeLists / tn-bird / [tn-bird] west nile virus and birds - [ Traduci questa pagina ]
Some birds will show a slight >eye tremor to premature feather drop to loss of
appetite to compltete loss >of body function. For birds in the wild, ...
www.freelists.org/archives/ tn-bird/09-2002/msg00048.html


Encyclopedia: Eye - [ Traduci questa pagina ]
For example, birds of prey have much greater visual acuity than humans and some,
like diurnal birds of ... Ocular tremor is eye tremor that assists vision. ...
www.nationmaster.com/encyclopedia/Eye

http://www.google.it/search?hl=it&ie=ISO-8859-1&q="eye tremo...