Wholesale-only categories and search engines?

I see that I can create a product category and restrict visibility of the category and its products to wholesale customers only. That's exactly what I want.

But I wonder if these products also be hidden from the search engines? 

That is, if a retail customer used (e.g.) google to search for an SKU that I have restricted to wholesalers only, will the product page show up in the search results?   And if so, what will the retail customer see if they click the link?

Thanks for any help.

Thanks Sean!