Estimating recreational trap-fishing effort for crayfish from zig-zag line transects, drone surveys and enforcement surveys

Estimates of recreational fishing effort and catch are needed to inform fisheries management, but such estimates can be challenging to obtain. We combined a zig-zag line transect survey of buoys, a fisheries enforcement survey and a drone survey to estimate recreational effort in the open-access trap fishery for signal crayfish (Pacifastacus leniusculus) in the sixth largest lake in Europe, Lake V & auml;ttern, Sweden. Using supporting variables such as size of nearby ports and bathymetry, our model-assisted estimate of total effort was 6400 (+/- 4300 CI) buoys during the three-weekend season. Using the frequency of buoys to traps as a constant, the total number of crayfish traps was estimated to be 25,500 (+/- 17,000 CI). The sampling design and methods presented are useful for ecologists and resource managers to design future multi-source surveys of recreational trap fishing effort

Frameless-Finding and Refining A Sampling Frame for Surveying Recreational Fisheries: Lessons from Estimating Swedish Harvest of Western Baltic Cod

To achieve sustainable fisheries, advice to management should be based on reliable science and unbiased data. Attaining quality data (i.e. precise and unbiased) on recreational fishing can be challenging, particularly when prior knowledge of the sector is limited and a proper sample frame of recreational fishers or vessels does not exist. In this study, a registry of access points was constructed for the Swedish south–west coast and used as a spatial sample frame in determining both effort and catches of the private boat fishery. Sampling dates, times for sampling, and access points visited were selected using probabilistic methods, ensuring unbiased results. The final multi-stage sampling design involved multiple strata, clusters, and probability selection methods and enabled first-time estimation of Swedish recreational landings of western Baltic cod by private boats to be used in stock assessment. Concurrent data collection covering aspects such as boat counts at access points, provided additional information on e.g. activity patterns. That additional information opens possibilities to refine the design of the original survey and optimize the sampling effort towards different goals, such as other fished resources. In this paper, we reflect on the challenges that limitations in initial information poses to the design and deployment of a new recreational fisheries survey. We suggest ways, whereby indirect sampling frames can be developed from initially incomplete or limited information to access the fishers and their catch. Our experience shows that, despite initial frame and knowledge limitations, full probabilistic methods are worth considering in data limited scenarios and that the design-based point estimates and variances they provide on recreational fishing effort and catches are useful in guiding initial management and the next steps of survey improvement

Second Workshop on Estimation with the RDBES data model (WKRDB-EST2; outputs from 2020 meeting)

This report shows how the new RDBES that is currently in development will be better able to support the recast EU Data Collection Framework (Regulation (EU) 2017/1004) than the existing RDB. The RDBES is an essential platform for MS and RCGs to fulfil their obligations towards documenting and improving data quality and designing and implementing regional sampling designs. The evaluation of data precision was performed using two complementary techniques. For relatively simple sampling designs it is possible to use analytical functions to calculate the precision (or a related statistical measure such as variance) of a statistical estimate. These calculations and implementations of them in R code are presented in this report. For more complicated sampling designs, the use of analytical functions is usually not feasible. In these cases, it is necessary to evaluate precision using numerical techniques, the main one of which is bootstrapping. This report discussed when bootstrapping is appropriate and gives several worked examples describing how bootstrapping can be applied in different cases. The evaluation of bias is a difficult subject and is hard to quantify. The approach followed in this report was to build on the previous work available in the ICES literature and identify and enumerate the main common sources of bias in catch sampling programs they describe. The information was collated and an evaluation performed as to whether data stored using the RDBES data format and reports issues from them can inform about the potential for bias in catch estimates. A set of example reports was coded that demonstrates the utility of the RDBES in relation to bias issues and can already help member states to identify how deviations in their sampling programmes and sampling variability may potentially lead to bias in their catch estimates

Meat tastes good, legumes are healthy and meat substitutes are still strange : The practice of protein consumption among Swedish consumers

Replacing some meat with grain legumes would benefit human health, the environment and agriculture. This study analysed legume and meat consumption practices by investigating consumer perceptions and competences relating to lightly processed grain legumes (LPL), legume-based meat substitutes (LBMS) and meat in Sweden, and how these (and demographic variables) influenced stated intention to change consumption. Major differences in consumer perceptions of LPL and LBMS compared with meat related to product attractiveness and status, with meat seen as more fun, popular, suitable in diets and for festive occasions, and tastier. Most consumers knew of the environmental impact of meat and health benefits of LPL. Country of origin, i.e. Swedish origin, was important for many consumers (especially for meat and women). Preferences relating to health and environmental impact were important for intention to decrease meat consumption. Perceived environmental impact was important for intention to change consumption of LPL, but taste, healthiness, weight control, ease of preparation and suitability in the diet were equally or more important. Leveraging stated consumer willingness and intention to eat more LPL by making LPL more accessible to consumers could increase their consumption. For LBMS, there are still important barriers in terms of taste, familiarity and overall attractiveness of these products that need to be overcome to increase their consumption in Sweden

Meat tastes good, legumes are healthy and meat substitutes are still strange - The practice of protein consumption among Swedish consumers

Replacing some meat with grain legumes would benefit human health, the environment and agriculture. This study analysed legume and meat consumption practices by investigating consumer perceptions and competences relating to lightly processed grain legumes (LPL), legume-based meat substitutes (LBMS) and meat in Sweden, and how these (and demographic variables) influenced stated intention to change consumption. Major differences in consumer perceptions of LPL and LBMS compared with meat related to product attractiveness and status, with meat seen as more fun, popular, suitable in diets and for festive occasions, and tastier. Most consumers knew of the environmental impact of meat and health benefits of LPL. Country of origin, i.e. Swedish origin, was important for many consumers (especially for meat and women). Preferences relating to health and environmental impact were important for intention to decrease meat consumption. Perceived environmental impact was important for intention to change consumption of LPL, but taste, healthiness, weight control, ease of preparation and suitability in the diet were equally or more important. Leveraging stated consumer willingness and intention to eat more LPL by making LPL more accessible to consumers could increase their consumption. For LBMS, there are still important barriers in terms of taste, familiarity and overall attractiveness of these products that need to be overcome to increase their consumption in Sweden

International Bottom Trawl Survey Working Group (IBTSWG)

The International Bottom Trawl Survey Working Group (IBTSWG) coordinate fishery-independent bottom trawl surveys in the ICES Area (Northeast Atlantic and North Sea) providing an important platform for the collection of additional data such as sampling larval sprat, stomach contents and fish parasites. These long-term monitoring surveys provide data for stock assessments and facilitate analyses of the distributions and relative abundance of fish. IBTSWG promotes the standardization of fishing gears and methods. This report summarizes national contributions in 2022–2023 and plans for the 2023–2024 surveys.In the North Sea, the surveys are performed in Quarter 1 and Q3. The Northeast Atlantic surveys are conducted mostly in Q1, Q3, and Q4 with a suite of 14 national surveys covering large areas of continental shelf extending from northern Scotland to the Gulf of Cádiz.The 2023-Q1 North Sea IBTS was impacted slightly by mechanical issues on one vessel, resulting in some of the Rectangles in the central North Sea being sampled with a single haul instead of the planned two. The 2022-Q3 North Sea IBTS was broadly complete, with the overall number of hauls comparable to previous years, though some Rectangles close to shore or with obstructions may not have had full coverage.The Northeast Atlantic surveys were mostly completed successfully, with the exception of the Scottish west coast groundfish survey in Q1 (cancelled due to vessel breakdown). There was incomplete survey coverage for some of the surveys, including the EVHOE survey (severe weather) and Portuguese groundfish survey (severe weather and mechanical problems). The Spanish surveys in the Gulf of Cádiz (cancelled in 2021) were undertaken in 2022.Recent updates to DATRAS, where the trawl survey data are stored, were summarised and data quality, including catch weights and species identification, was reviewed.IBTSWG met with members of various data users, including relevant stock assessment groups, such as WGNSSK, WGEF and HAWG, presenting summaries of relevant surveys.A proposed new survey trawl, following on from earlier workshops and intersessional discussions, was reviewed. Several nations have conducted, or are planning, gear trials. Pending fine tuning required for the gear, the main aspects of the new trawl have been agreed. IBTSWG plan to hold an intersessional meeting to discuss implementation and to ensure communication and involvement of relevant experts on survey design and survey indices