I'm sure there will be a number of people who will respond to this
question, but hissing in general from a ferret is a form of communication
and I think a way of letting you know how tough they are.  There are a
number of variations to the hiss and I believe that each one has a
separate meaning.
 
There is the hiss that ends on a higher note than it started.  In our
household, the ferrets seem to make this kind of hiss when they are
unhappy about a situation, and unhappy that you interrupted what they
thought was good fun.  This hiss happens when we stop activities like
chewing on mom's feet at 3 in the morning, scrapping with another ferret
that we have pulled the loser from, and when we don't give that damn
piece of red licorice that they have been patiently waiting for, for the
last 2 minutes.
 
There is the hiss that ends on a lower note than in started.  In our
household, I have seen this one associated more with other ferrets than
with us humans.  The hiss seems to come when they are more serious about
their task at hand, and for example, have a stronger drive to kick one
ferret out of the bed they have claimed for their own.
 
There is the hiss that sounds even in tone all the way through.  This
seems to be the warning hiss, the "stay back or there will be trouble"
hiss, the sizing up the situation hiss.  This hiss I see when I challenge
the ferrets directly.  I stare them straight in the eyes and slap my hand
down in front of them.  With the right ferret, I get a response of
waiting, and then the hiss.
 
There are probably more hisses than we know of.  And it is possible that
my poor brain has even mixed up my careful study of the hisses.  But
regardless of what each one means, there are different hisses that do
tend to be heard during certain situations.  The english language has so
many subtleties that it can be confusing.  Animal communication can be
just as complicated.  We don't really hear all the sounds they make, and
every now and again, I am blessed with a ferret who teaches me that when
I thought I heard them all, there are a few more to add to the bag.
 
betty and her blur o'fur
for the love of ferrets
[Posted in FML issue 3762]