Copied this from a Guardian article of 2011. Bit of an Eye-opener ?
"In England and Wales as long as you are in possession of a £27 rod licence and have permission from the water's owner, the Environment Agency states that on any given day an angler may remove 15 small (up to 20cm) native species including barbel, chub, common bream, common carp, crucian carp, dace, grayling, perch, pike, roach, rudd, silver bream, smelt, tench and zander (non-native) as well as one pike of up to 65cm and two grayling of 30-38cm"