Just like you trained the other ferret to a squeaky toy, you can
train the deaf ferret to a light.  Even deaf ferrets often hear some
frequencies (pitches) and if you associate the light with the squeaky
toy you currently use and add something else, like a bell or whistle to
it, you will not only have them trained to the light (flash it in the
same pattern as you use the bell, at the same time), you will have
another sound that might work.
 
My deaf beauty Sir Walter (of Raleigh) used to respond to something!
Not sure what, but from a dead sleep he roused to respond when I used
the bell to call the others.  My current deaf boy, Rocky Bobbles, had
meningitis.  He is not the brightest bulb in the box and nothing works
with him!  I think the pattern of hearing loss may be what affected
their responses differently.
 
I am copying this to Wolfy, so she can share her site and info she
collected with you, too.
 
--
renee :)
It's amazing how much can be accomplished if nobody cares who gets the
credit!
Ferret Emergency Response, Rescue & Evacuation Team (F.E.R.R.E.T.)
http://www.ferretemergency.org
International Ferret Congress
http://www.ferretcongress.org
American Red Cross
http://www.redcross.org
[Posted in FML issue 5375]