I don't think barbel welfare is at the top of the list on adverts such as this. Modern barbel fishing is basically carp fishing tactics on rivers. The trouble is, barbel are not as intelligent as carp, and they suffer more from pressure. Carp are more Doctor Stephen Hawking while barbel are more like Wayne Rooney (strong and muscular but not the sharpest hooks in the box)! Constant pressure on known swims (such as my local Yorkshire Swale and parts of the Trent) sees the same fish hooked repeatedly. I can imagine that it will affect their social behaviour. Most anglers just want to catch fish at any cost and the fish are pressured for 9 months of the year. I won't fish the Swale for barbel and try to lightly fish several different rivers where the barbel have no names. I have caught 3 barbel this summer from three different rivers. I fish for many other species as well, so that is quite enough.