There are several but it is a pain tracking through the data base, apparently most are cold water and prevalent in Scotland but also small ones throughout UK, check local hardcopy (IE, books) at nearby colleges. Not many fish eat them.
I did a google search for info and found an aquaria central thread with some links (some dead) and a little info. It's not much, and I don't normally like referring people to other threads (yes, I KNOW there is a search function, but how will searching foster new and interesting ideas and discussions)... wow, digress much?