My suggestion:
 
Post to your list wearing your administrator's hat that
politically-oriented posts not relating to fishes is not relevant and to
please take it to another forum.
 
Tell the woman that offended the list that this is your offical policy
and she should not violate it in the future.
 
If she continues to make non-topic postings, delete her.  If she comes
back mad as hell, delete her again and tell her not to come back.  If she
does again, add a filter, delete her, notify her admin.  At each step
make sure you tell her that her behaviour is unacceptable.
 
As for "policing" signatures, I have a very strong sentiment AGAINST
that.  A signature is just that, sort of an identifying mark.  Yes, many
people put cutesy quotes or personal policial messages in theirs (hell,
even _I_ have THREE political messages hidden in mine, can you find
them?), but it really shouldn't be any big deal and certainly not grounds
for banning.  Sig. content should be ignored if you don't like it.
 
Of ourse, I have a very libertarian viewpoint and advocate limiting her
posts ONLY because it is an improper forum, definately not on content.
 
Your milage will, of course, vary.
 
____        Robert A. Hayden          <=> [log in to unmask]
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