Stuart, I don't think that Alan, who started this thread, suggested that anyone was ONLY a single species angler, he was simply asking where all those who would normally have been posting on a thread for Barbel Fishing had disappeared to. As usual Alan's request was met with some good humour.
Some have a preference to particular species of fish above others but I doubt anyone on FM would fish ONLY for one specific species, not even me, although I must admit to being a flowing water man. I did go through a phase going after Scottish bream in the 70's but the wife very soon knocked that out of me

AND I did spend a considerable amount of time fishing for dace; living within 2 mile of the Wear I'd be a fool not to

Ive even 'stalked' them, watching their migration at various times of day/year, sadly that special dace never came my way, probably never will now.
As for fishing in the North for barbel, (the Trent??) you're only pretending
I do actually know one angler who fishes for chub 99.9999% of the time he spends fishing but I heard that even he had a dabble for carp and tench during the last river close season. Although his 0.0001% would equate to a fair bit of fishing time for most normal anglers.