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2 Annual Palinurus elephas landings from all fishing gears (not effort related) in the south Wales shellfish permit area (formerly the South Wales Sea Fisheries Committee Area). Data from the Welsh Government. 

2 Annual Palinurus elephas landings from all fishing gears (not effort related) in the south Wales shellfish permit area (formerly the South Wales Sea Fisheries Committee Area). Data from the Welsh Government. 

Source publication
Technical Report
Full-text available
Populations of the crawfish, Palinurus elephas, in Welsh waters have declined significantly since the 1960s and 1970s when changes in fishing practice took place. This large benthic crustacean is a key species in reef features within existing marine Special Areas of Conservation (SACs) and also within the wider context of the Welsh marine ecosystem...

Contexts in source publication

Context 1
... Contract Science Report No 989 Organisation does not hold information on fishing being carried out by foreign vessels within the six to 12 nm zone that is landed outside the UK. It is possible therefore that a proportion of fisheries removals from the Welsh crawfish population is not accounted for nationally and would not be able to be controlled through the introduction of Statutory Instruments. If the catch by foreign vessels was found to be significant or increasing, this could be addressed by seeking a derogation to make the Welsh SI applicable to the relevant Member States in order to facilitate and maintain recovery of crawfish in Welsh waters. Prohibitions on landing are likely to be most effective in pot and dive fisheries as there are likely to be high survival rates of live returns from these fisheries. Net fisheries can however result in mortalities of captured crawfish depending on the length of time they have been caught in the net and on levels of damage through contact with the net. Further information on the spatial distribution of crawfish captured in net fisheries could permit area prohibitions in order to mitigate any fishing mortality if it was considered to be a significant problem. The effectiveness of a Welsh landing prohibition, in terms of recovery of stocks, will also be affected by the source of recruitment into Welsh populations. If larvae are being produced by populations in other areas and then brought to Welsh waters through the movement of tides and currents, the level of recruitment will not be affected by a Welsh prohibition on landing crawfish. However, in this situation a landing prohibition would increase population numbers and could eventually benefit recruitment in an area outside Welsh waters. A regional sea or EU level prohibition could aid recovery in Welsh waters if it was implemented to protect an area with proven larval connectivity to Welsh crawfish populations. Should the source of recruiting individuals be from within Welsh stocks, the potential rate of recovery could be increased through both the reduction in removals from the population by fishing, and through increased recruitment to the resident population. A prohibition on the landing of crawfish in Welsh waters could contribute to the recovery of crawfish. The rate of recovery facilitated by such a management measure in the context of the depleted status of Welsh crawfish populations is not clear however. Preventing the removal of individuals and potentially enhancing recruitment would both increase the abundance of crawfish and result in changes in length frequency distribution towards one that was indicative of GES. These potential benefits may make this a more effective management measure in terms of recovery, than one which only protects part of the population (e.g. MLS) or has a spatial or temporal component (e.g. area or seasonal closures) which still permitted fishing activity. It may be appropriate to review a landing prohibition in a recovering population in order to determine if other management measures, which allowed the removal of individuals, could be introduced. It has been shown that pot fishing is the least effective method for catching crawfish although it is relatively environmentally benign (Eno et al. , 2001). Dive fishing has the potential to cause the least disturbance to the surrounding habitat; however it can result in quite high catch rates and the potential for localized depletion of the stocks. The use of nets for capturing P. elephas is the most effective, from a fisheries point of view, and there are concerns relating to damage to other marine life and potential bycatch issues. Prior to considering any prohibitions relative to fishing gear it is important to assess to what extent the different methods are used and in what areas. Both net and pot fisheries have continued to land crawfish in recent years, however, the dive fishery has declined and is now almost non-existent (Marine Management Organisation; Figure 1.2). It is important to gather further data about the geographical extent of each fishery and the effort deployed in order to determine the potential for any prohibition to affect a recovery in the population. A further consideration would be changes in fishing type due to the prohibition of a single fishing gear ...
Context 2
... Contract Science Report No 989 Dive fisheries can also affect the behaviour of spiny lobsters. A study in Florida observing Panulirus argus showed that there was increased dispersal of individuals following a period of fishing in an area that had been previously closed to fishing (Davis, 1977). It was suggested that this dispersal may be as much related to perturbation by divers as reduction in numbers and indicated that increased dispersion could have impacts in terms of exposure to predators, and disruption of social structure. A shellfish permit scheme introduced in the South Wales Sea Fisheries Committee (SWSFC) area in 1980 has resulted in the collection of catch and effort data for the crawfish fishery in this area. The annual landings data, broken down by fishing type, are shown in Figure 1.2. A report on data collected via this scheme was produced by Davies (1999) for the period 1980 to 1997. This showed that landings were under two tonnes per year with the exception of the period from 1990 to 1993 which saw a peak to 12 tonnes in 1992 (Davies, 1999). The peak in landings observed around 1992, which can be attributed to three boats, was due to the identification of an area of inshore reef where crawfish were carrying out a migration and nets were specifically set between two areas of kelp (P. Coates, pers. comm.); however, the fishery became uneconomic by 1993. Landings from the pot fishery have shown a general pattern of decline since 1980 when annual landings were around 1.2 tonnes, to recent years where landings have remained largely below 0.5 tonnes since 1993 (Figure 1.2). That is with the exception of 2007 which saw the highest annual landings from the pot fishery during the data collection period at 1.4 tonnes. The dive fishery landed around 0.4 tonnes in 1980 and 1981 but no commercial dive fishing has been recorded in the south Wales area since 1986. Data from the Marine Management Organisation for the period 2000 to 2011, show that some commercial diving took place in 2010 but that it made up a small proportion of the total catch (<10 kg). Total annual landings of crawfish since the peak in 1992 have remained relatively low and landings from Welsh vessels have remained at less than two tonnes per year since 2000 (Marine Management Organisation). Although the volume of catch remains low and it is not a targeted fishery, it is of significant value to fishermen with the two tonnes landed by nine vessels in 2007 having a value of ...