Angler catch data as a monitoring tool for European barbel Barbus barbus in a data limited recreational fishery

Large bodied freshwater fishes can be important target species for recreational anglers, with some species introduced intentionally to diversify angling experiences. European barbel Barbus barbus is an important target species in many riverine fisheries, including the River Severn and its River Teme tributary, western England, where it has supported a catch-and-release recreational fishery for approximately 50 years. The River Teme was renowned for the quality of its barbel angling from the 1980s. Since 2007, angler dissatisfaction has increased substantially in this fishery, being associated with alleged declines in the number of barbel being captured and in their population abundances. As there were few data available at that time to investigate these declines, data from periodic electric fishing surveys and some angler catch data were sourced. Analyses revealed temporal declines in the number of sampled barbel during electric fishing surveys, although the number of surveys was low, varied between years and did not target barbel specifically. Analyses of four angler catch data sets (1995–2022) involving more than 1000 captured barbel of 0.5–5.3 kg also revealed significant temporal declines in barbel catches (by number and catch-per-unit-effort). These catch declines were generally coincident with reductions in angler presence and effort on the river, suggesting low catches were a driver of angler dissatisfaction. These results provide empirical support for angler claims of substantial declines in barbel catches and abundances, and emphasise that even limited volumes of angler catch data are useful for understanding temporal changes in exploited but data limited fish populations. • Large catch declines alleged by anglers in a river fishery based on introduced Barbus barbus. • Population density data from monitoring insufficient for analyses. • Angler catch data analyses provide alternative method. • Large temporal decline in catch rates of B. barbus. • Results corroborate angler claims of catch rate and population declines.