Sarcoptic mange mites are usually very difficult to find and diagnosis is
often made based on symptoms.  Usually, the animal is EXTREMELY itchy,
often causing raw sores and wounds from scratching.  These mites are found
all over the animal, not only in the ears.  The ear mite is very similar
to the sarcoptic mange mite, especially to the untrained eye.  It is very
possible since the mite was found in the ear that the ferret has ear
mites.  Ear mites are common and easily treated by your vet.  Ear mites
cause a thick dark brown to black exudate to form in the ear.  the gunk
consists of ear wax and mite feces (yuck).  Mites should be eliminated as
soon as possible to prevent damage to the ears and to prevent the spread
to other ferrets in the household.
 
Either way, I would have the vet check things out.  Good luck and let us
know what you find out.
 
Erica
Snoball, the dog
Ripley, Max, and Jinx, the kitties
Fitz, Buster, and introducing Milos, the ferrets...
and baby Honey (ferret) waiting at the Rainbow Bridge
Also at the bridge:  Purr-Furr (kitty) Nerd, Nubbins, and Dusty (dogs) and
Farli (ferret)
All of whom are much loved and deeply missed!
[Posted in FML issue 3625]