User blog comment:Nmcconnell/"Please log in to post a comment on this wiki"/@comment-452-20140511153408

If your wiki is aimed at children, it should already restrict anon participation.

Use Special:Contact and let them know.

If you just have a comment spam problem, then it should be possible for anon comment creation to be disabled while allowing anons to still do other things.

In general, commenting is usually kept open, so be sure to link to a bunch of examples of spam/vandalism.