Several times during "Redwall", the sex of Killconey the ferret changes. Sometimes it's a "he" and sometimes it's a "she". Haven't these guys ever heard of proofreading?
Brian Jacques, the author, verified on the official Redwall site that Killconey was infact male. No female villians appear in the series until the Pearls of Lutra.
Woah woah woah, hold up! No female villians? What about the CAT, man? Tsarmina was, like, even more evil than Tinky Winky! And that's EVIL, man! It's like, BAD! And stuff!
...
I'm done.