Voluntary angler logbooks reveal long‐term changes in a lentic pike,Esox lucius,population

Sixty‐two years of voluntarily collected angling logbook data from a large natural Danish lake were used to study variation in pike, Esox lucius L., CPUE (catch per unit effort), expressed as no. of captured pike per boat trip, as an index of stock size. Pike CPUE was positively related to pike release rate by anglers and negatively affected by certain commercial fishers. The stocking of young‐of‐the‐year pike and a fishery‐dependent index of perch, Perca fluviatilis L., abundance (which may be pike prey or predator depending on size) did not correlate with pike CPUE. Analyses of the size distribution of pike, based on sizes of annual record trophy pike captured by anglers, confirmed the negative impact of commercial pike fishing and revealed a positive influence of air temperature. It is concluded that high‐quality angler logbooks that record effort and catch can be a cost‐effective tool to inform lake fisheries management by revealing long‐term population trends. Further, state space modelling, a statistical technique not yet seen in recreational fisheries science, is recommended as a tool to model proxies for population dynamics from angler logbook data.     

Angler behaviour and implications for management ‐ catch‐and‐release among marine angling tourists in Norway

The role of recreational fisheries in the competition for marine resources is increasingly recognised. Their contribution in stock dynamics needs to be accounted for in assessments and management. Management regulations should be based on scientific advice on human and biological dimensions to be effective in reaching their goals. A survey among marine angling tourists staying in fishing camps in two study areas in Norway was conducted to study catch‐and‐release (C&R) behaviour. Although C&R has been assumed to be low in many marine recreational fisheries, this survey showed that for some species, more than 60% of the catch was released. As C&R may be associated with post‐release mortalities, the current management system could be inefficient towards its aim of reducing fishing mortality. It was concluded that it is necessary to quantify release mortalities, to consider C&R behaviour in future management decisions, and to minimise the potential negative impacts of C&R through handling guidelines.     

Normative considerations for recreational fishery management: a bioeconomic framework for linking positive science and normative fisheries policy decisions

Fishery science and management are concerned with both positive, what happens in a fishery system, and normative, what management should do, questions. Rarely are normative criteria discussed as openly and transparently as the positive techniques and assumptions. Instead, normative criteria are often held implicitly, and often goals, and objectives are defined without careful thought about the normative criteria from which such goals, and objectives derive. Management involves three components: system attributes and dynamics, management options and goals and objectives that stem from normative criteria by which outcomes are judged. There is a need to consider normative frameworks and criteria carefully because normative criteria are intrinsic to any management process. This paper motivates the need to consider normative frameworks and criteria carefully, explores issues associated with developing normative frameworks and criteria that articulate positive science, discusses specific issues to consider when developing normative frameworks for recreational fisheries and provides the bioeconomic framework as an example of a normative framework useful for recreational fisheries.     

An assessment of catches of shore sport fishing competitions along the coast of the Maltese Islands: Implications for conservation and management

Competitive shore‐based sport fishing is a popular recreational activity in the Maltese Islands. However, prior to this study, no scientific research surveys had been carried out during sport fishing competitions to investigate catches. Collaboration with Maltese sports fishermen was developed to target sustainable management. Recreational fishing catches were recorded between July 2012 and December 2015 by means of 1,633 roving‐access creel surveys, conducted during 79 sport fishing competitions, totalling a fishing effort of 7,548 hr. A total of 29,916 fish belonging to 80 species from 26 different families were caught at a mean catch‐per‐unit‐effort (CPUE) of 4.16 fish angler/hr (SD ± 3.79) and 0.18 kg angler/hr (SD ± 0.17) but with seasonal variation. Catch‐and‐release practices were implemented by all Maltese sport fishing clubs, however, the mean mortality rate stood at 35.5% (SD ± 42.1), indicating that more effort is required to improve survival of fish. The study outcomes provide conservation recommendations.     

Integrating fishing and conservation in a risk framework: A stochastic population model to guide the proactive management of a threatened freshwater crayfish

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Changes in angler participation and demographics: analysis of a 17‐year licence stub return system for Atlantic salmon

Abstract Patterns of change in angler participation and demographics were examined for the recreational Atlantic salmon, Salmo salar L., fishery in Newfoundland and Labrador, Canada. An analysis of a licence stub return system, 1994–2010, showed a significant decline in resident angler participation, but this was not consistent across all regions of the Province. Mean age of anglers increased significantly, varying from 39.0 years in 1994 to 46.5 years by 2010. In some regions, mean age rose by over 12 years since the mid‐1990s, reflecting a decline in the recruitment of younger anglers. The return rate of angler logs also declined over time and was found to vary by age, sex and area of angler residence. Women and older anglers, and those living in specific rural areas had a greater tendency to return a record of their catch history than men and younger anglers. Identified changes in participation and demographics, which can affect exploitation and ultimately abundance, could be used to develop management measures that would maximise both harvest and socio‐economic benefits to the varied users of the resource.     

Movement dynamics of smallmouth bass (Micropterus dolomieu) in a large river‐tributary system

Smallmouth bass, Micropterus dolomieu Lacepède, movement dynamics were investigated in a connected mainstem river‐tributary system. Smallmouth bass moved large distances annually (n = 84 fish, average = 24.6 ± 25.9 km, range = 0.03 to 118 km) and had three peak movement periods (pre‐spawn, post‐spawn and overwintering). Movement into and out of tributaries was common, but the movement between mainstem river and tributary habitats varied among tagging locations and season. In general, a large proportion of fish that were tagged in tributaries moved out of the tributaries after spawning (22/30 fish). Because of the importance of fish movement patterns on population dynamics, the observed individual variability in movement, quantified using a hierarchical model, and the potential for long‐distance movements are important considerations for smallmouth bass conservation and management. In addition, mainstem river‐tributary connectivity appears to play an important role for smallmouth bass during key life history events.     

The home range and behaviour of yellow‐stage European eel Anguilla anguilla in an estuarine environment

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The biodiversity value of marine protected areas for multi‐species fishery management in the Gulf of Maine

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Evaluation of observer‐ and industry‐based catch data in a recreational charter fishery

There is international recognition for greater inclusion of recreational fisheries catch data in species, fisheries and ecosystem assessments. Recreational charter fisheries provide important social services and contribute to total species catches. This study compares and validates industry logbook catch and effort data (1,357 trips) against observer data (154 trips) across six ports in a recreational charter fishery in eastern Australia. The mean numbers of clients and fishing effort (hours) per trip varied inconsistently between data sources and among ports. Logbooks did not adequately report released catches, and the mean number of species retained per trip was consistently underestimated in logbooks compared to observer data. For both data sources, catch rates of total individuals and key species displayed similar trends across different units of effort; catch per hour, client, client/hour and trip. The mean catch rates of total individuals and most key species, except those retained for bait, were similar across data sources, as were estimates of total fleet harvests. The length compositions of retained catches of some key species displayed truncation of larger organisms in the observer data whereas other species did not. Despite the shortcomings of the logbook data, future fishery and species monitoring strategies could include industry and observer data sources.     

Reflections on the influence of a synthesis of circle‐hook evidence on the angling community and conservation policy and practice

1. Understanding how different forms of environmental evidence inform the actions of different stakeholders is useful to improve how we share knowledge with knowledge users. Reflections on a literature review that we published in 2004 on circle hooks as a tool for fish conservation in the recreational fishing sector identified a number of ways in which that synthesis was influential.
2. The article has had direct influence on policy and regulations in a number of countries, but there were even more examples of where the article has been used to influence voluntary guidelines. The article also contributed to formally defining circle hooks, which was necessary from a regulatory and enforcement perspective.
3. The recreational fishing community has also embraced the work, with numerous angling articles based on the literature review appearing in the media and with some angler organizations pushing for the adoption of circle hooks. The fishing tackle industry has also responded with evidence that circle hooks are now more widely available in stores with more hook design options to suit diverse recreational fisheries. In addition, the influence of the article has extended beyond the recreational sector to commercial fishery issues that span several taxa. The research agenda from the article helped to direct research for more than a decade and has since been updated.
4. Overall, this review was timely in that it provided various knowledge users with credible information synthesized in a thoughtful manner at a time when there was interest and need in exploring circle hooks as a tool to enhance the conservation of angled fish. Although this was not a systematic review, it still served as a form of evidence synthesis that gave diverse knowledge users information to guide them in their decisions.

     

Explaining recreational angling catch rates of Eurasian perch,Perca fluviatilis: the role of natural and fishing‐related environmental factors

Angling catch records are frequently used to reveal fish population developments. It is therefore important to understand the determinants of angling catches. This study focused on angler‐related, biotic and abiotic factors influencing catchability of Eurasian perch, Perca fluviatilis L. A multi‐lake (21 lakes) study based on angling diaries collected in Mecklenburg‐Vorpommern, Germany (2006/2007), found that angler‐related factors such as fishing experience, species preference and bait/lure type had a large impact on perch catch rates. Additionally, environmental conditions (nutritional status and water transparency) affected either the size or the number of perch caught by anglers. Catch rates varied seasonally, which was confirmed by an experimental fishery on a gravel pit (2008). This portion of the study showed that altered food availabilities in the course of the year caused food limitation in perch, which in turn facilitated high catch rates and female‐biased exploitation in autumn. It is concluded that both angler‐related and abiotic factors interact affecting perch catch rates and size of perch captured in recreational angling.     

The conservation status of Sabellaria alveolata (L.) (Polychaeta: Sabellariidae) reefs in the Bay of Mont‐Saint‐Michel

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Assessing the effectiveness of a long‐standing rocky intertidal protected area and its contribution to the regional conservation of species,habitats and assemblages

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Eurasian perch Perca fluviatilis growth and fish community structure,inside and outside a marine‐protected area in the Baltic Sea

Growth of Eurasian perch Perca fluviatilis L. and fish community structure between sites within a marine‐protected area (MPA) and unprotected sites in the Baltic Sea were examined. Von Bertalanffy, logistic and Gompertz growth models were fitted to P. fluviatilis length at age data, and the logistic model was the most parsimonious for growth between locations. A larger mean maximum size (L_∞) and a smaller instantaneous growth rate (g) were found within the MPA. All three models also predicted that after age seven, fish inside the MPA would be larger. Community structure differed with more P. fluviatilis collected outside of the MPA, and more roach Rutilus rutilus (L.) and bleak Alburnus alburnus (L.) collected inside the MPA. These growth differences may be indicative of recreational fishing effects on P. fluviatilis outside of the MPA, a result of complex interspecific and intraspecific species interactions, or other undetected environmental variation between locations.     

Comparing the utility of fishery‐independent and fishery‐dependent methods in assessing the relative abundance of estuarine fish species in partial protection areas

In partial protection management areas such as Recreational Fishing Havens (RFHs) where commercial fishing is prohibited there are fewer sampling methods available for quantifying the relative abundance of species. Consequently, a framework is needed in such areas to decide whether sampling should be based on: (1) fishery‐independent techniques; (2) fishery‐dependent methods that rely on recreational fishery harvests; or (3) a combination of the two. This study compared fishery‐independent data derived from baited remote underwater video stations (BRUVS) and independent fishing surveys (IFS) with fishery‐dependent data based on recreational angler surveys (AS) to identify the fish species that were best enumerated by each method in two Australian RFHs. Each method captured/detected disparate species and each consistently showed correlations with the relative abundance of particular suites of species. The species that were correlated with and best enumerated by BRUVS were Microcanthus strigatus (Cuvier) and Pelates sexlineatus (Qouy & Gaimard); those correlated with IFS were Gerres subfasciatus Cuvier, Girella tricuspidata (Qouy & Gaimard), Mugil cephalus L. and Pomatomus saltatrix (L.); and those correlated with AS were Platycephalus fuscus Cuvier and Acanthopagrus australis (Owen). By identifying the species that were best quantified by each method, this study facilitates accurate monitoring of key species within RFHs.     

Evaluation of a river classification system as a conservation measure in the management of Atlantic salmon in Insular Newfoundland

In an effort to address the decline in abundance of Atlantic salmon, Salmo salar L., in insular Newfoundland rivers, resource managers introduced a River Classification System (RCS) in 1999 to assist in the management and conservation of the resource. The RCS set daily and seasonal bag limits in the recreational fishery on a river by river basis. An analysis of the catch and effort data before and after the implementation of the RCS showed an overall decline in the number of retained salmon after the implementation of the RCS, but no change in overall effort. Upon closer examination, it was found that retention increased on Class I rivers, which had the highest allowed retention, but declined on the other class rivers. On one particular river (Harry's River), which alternated classifications from 2007 to 2010, it was found that exploitation rates increased as allowed retention increased. Newfoundland salmon anglers appear to be retention anglers and therefore the RCS was an effective tool for diverting catch and effort to specific rivers by changing retention limits.     

Fishing operations and adaptive strategies of small‐scale fishers: insights for fisheries management in data‐poor situations

Small‐scale fisheries' management is complex given its multigear, multispecies nature; despite this, fishing effort has usually been controlled by nominal units, ignoring changes in effective fishing effort. This study aimed to understand the adaptive strategies of small‐scale fishers in San Felipe, Yucatan, Mexico through an analysis of their fishing operations. Minor changes in trip numbers among three seasons were observed, but increases in fishing time, depth and travel costs from one season to another at the operational level were found. It was also evident that high value species at the beginning of the season were gradually replaced by low‐value finfish as the season progresses. The results provide insights for new adaptive management strategies according to fisher's adaptive responses. For instance, using boats or fishing trips as fishing effort units in Yucatan may not be the most appropriated unit for management, as fishers adapt their strategies at different levels.     

The use of spearfishing competition data in fisheries management: evidence for a hidden near collapse of a coastal fish community of Galicia (NE Atlantic Ocean)

The use of commercial catch statistics to estimate overfishing consequences has been criticised, but alternative long‐term data sets are rare. Long time‐series data sets from recreational fisheries competitions have been used to infer trends in coastal fish communities. Here an historic archive (1953–2007) of recreational spear fisheries in Galicia (NW Spain) was employed to estimate long‐term changes in coastal ecosystems. Using generalised additive regression models, decreases in the abundances of coastal rocky reef fishes of up to 76% over the last 50 years were found. In the same period, the mean body weight also decreased by 76%. In addition, relative catch frequency has decreased for the most valuable commercial species. Overfishing, amongst other human impacts, has brought these ecosystems so close to collapse that it is urgent to implement measures to ensure their recovery.