There’s no way to batch report spammers. There might be something in SpamBrainz once that rolls around, but please, please, please do not report spammers until we have SpamBrainz, unless there’s something that really needs urgent attention. (E.g., a spammer that continues to add spam edits after its first few edits, or a spammer that links to something truly heinous. Pharmacy, real estate, etc. spammers are just annoying, but we’ll deal with them when we have a better framework for it (SpamBrainz).)