Guys, please don't blame the admins for this. this is a forum at the end of the day which means that anybody can join and anybody can post. This forum would not be what it is today if we didn't have that type of privileges.
A possible fix for the issue:
Any new members who are trying to join should have to answer a question as to why they are interested in joining the site, and admin can vet them before they are allowed access to the site.
Alternatively, a rule for new members posting where the post gets vetted by admins before it's posted.
I was thinking along those lines as well... When I joined one of the other forums (think it was boatfishing) I had to ID the fish in their logo before becoming a member. SL could do something like asking what the common name is for a Cape Salmon... And if you're not from round here, give them the chance of mailing the mods for the answer... Just a thought.