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There are often limited data available to support the sustainable management of recreational fisheries. Electronic citizen science platforms (e.g., smartphone applications) offer a cost-effective alternative to traditional survey methods -but these data must be validated. We compared sea trout (Salmo trutta) data from a Danish citizen science platform with three independent traditional surveys: a roving creel survey, an aerial survey, and a recall survey. The comparisons include fisheries data (e.g., catch, release, effort, and fish size structure) and demographic descriptors (e.g., age) that were collected within the same spatial and temporal frame. We found general alignment between recreational sea trout catch and effort data that were provided by citizen scientists, or collected by more traditional survey methods. Our results demonstrate that citizen science data have the potential to supplement traditional surveys, or act as an alternative source of catch and effort data. However, results were from a highly specialized fishery within a limited spatial and temporal frame, so more research is needed to assess their relevance over time and to a broader set of fisheries. La disponibilite de donnees pour appuyer une gestion perenne des peches sportives est souvent limitee. Si les plateformes electroniques de science citoyenne (p. ex. applications pour telephones intelligents) constituent une option de rechange peu couteuse aux methodes d'enquete traditionnelles, leurs donnees doivent etre validees. Nous avons compare des donnees sur la truite brune (Salmo trutta) d'une plateforme danoise de science citoyenne a celles de trois enquetes independantes, soit une enquete par interrogation itinerante de pecheurs, une enquete aerienne et une enquete memoire. Les comparaisons comprennent des donnees sur la peche (p. ex. prises, lachers, effort et structure par tailles) et sur des descripteurs demographiques (p. ex. age) qui ont ete recueillies dans le meme cadre spatial et temporel. Nous constatons une concordance generale des donnees de prises et d'effort sur la truite brune fournies par des citoyens scientifiques et obtenues par des methodes d'enquete plus traditionnelles. Nos resultats demontrent que les donnees issues de la science citoyenne pourraient fournir un bon complement aux enquetes traditionnelles ou constituer une source differente de donnees sur les prises et l'effort. Cependant, comme ces resultats concernent une peche tres specialisee dans un cadre spatial et temporel restreint, plus de travaux sont necessaires pour evaluer leur pertinence dans le temps et pour un ensemble plus large de peches. [Traduit par la Redaction], Introduction Recreational fishing is a popular activity in many regions of the world, with participation rates approaching 30% of adults in some countries (Arlinghaus et al. 2015). Recreational fishers invest [...]

Catch‐and‐release angling is common in recreational fisheries, but post‐release mortality (PRM) may be high. We conducted a controlled field experiment to estimate mortality of released snapper Chrysophrys auratus. Recreational fishers caught 960 snapper from three depth strata (<15, 15–25, 26–40 m) that were either lip‐hooked, foul‐hooked or gut‐hooked. A bottom longline vessel caught 162 lip‐hooked fish in shallow water to serve as controls. Fish were held in 15‐m deep holding nets. All control fish and 80% of treatment fish survived, with anatomical hook site and capture depth significantly predicting mortality. Probability of mortality was lowest for lip‐hooked fish in shallow water (5 m = 0.00, 95% CI [0.00, 0.03]), but increased rapidly to 20 m (0.24, 95% CI [0.2, 0.3]). Mortality of foul‐hooked fish increased steadily with depth from 0.05 (95% CI [0.00, 0.78]) at 5 m to 0.65 (95% CI [0.13, 0.96]) at 40 m. Gut‐hooking resulted in high mortality at all depths but a low sample size resulted in high uncertainty of estimates. Our results indicate that snapper PRM can be reduced by fishing in shallow water and by mitigating gut‐hooking, possibly by using large circle hooks. [ABSTRACT FROM AUTHOR]

We compare estimates of recreational harvest provided concurrently by two fundamentally different survey designs: an offsite panel survey and an onsite aerial-access survey. Aerial-access estimates for the five most commonly caught species were 2% to 50% lower than the panel survey estimates, with the greatest differences apparent for the least commonly caught species. Boosted regression tree modelling of spatially and temporally disaggregated harvest estimates identified a consistent pattern of temporal bias that explained much of the difference between the two sets of estimates. An analysis of web camera-based traffic data collected concurrently at key boat ramps confirmed that the selection of days for the aerial-access survey was biased towards lower effort days in three out of four temporal strata. Some evidence of under-reporting of zero catch trips by panelists was also identified by boosted regression tree modelling of catch per trip data. Nonetheless, the estimates provided by the two surveys were still remarkably similar given the range of potential biases that the two contrasting survey approaches were potentially subject to. Comparative studies such as this are rare, but they provide greater insights than introspective evaluations of single surveys and therefore greater certainty in the future. Nous avons compare des estimations de prises sportives fournies par deux schemas d'evaluation fondamentalement differents, soit une evaluation hors site reposant sur un panel et une evaluation sur place basee sur l'acces aux zones de peche. Les estimations basees sur l'acces aux zones pour les cinq especes prises le plus souvent etaient de 2% a 50% plus faibles que les estimations par panel, les plus grandes differences etant apparentes pour les especes prises le moins souvent. La modelisation par arbre de regression de niveau eleve d'estimations de prises desagregees dans l'espace et le temps a revele un motif coherent de biais temporel qui expliquait une bonne partie des differences entre les deux ensembles d'estimations. Une analyse de donnees de trafic par cameras web recueillies simultanement a des rampes d'acces a l'eau cles a confirme que la selection des jours pour l'evaluation basee sur l'acces aux zones etait biaisee vers les jours d'effort plus faible dans trois strates temporelles sur quatre. Certaines indications d'un sous-signalement des sorties a prise nulle par les panelistes ont egalement ete relevees par la modelisation par arbres de regression de niveau eleve des donnees de prises par sortie. Quoi qu'il en soit, les estimations fournies par les deux evaluations etaient remarquablement semblables au vu de l'ampleur des biais possibles auxquels les deux approches d'evaluation distinctes etaient potentiellement assujetties. Si de telles etudes comparatives sont rares, elles fournissent plus d'information que les etudes introspectives d'evaluations uniques et donc une plus grande certitude pour l'avenir. [Traduit par la Redaction], Introduction Fisheries managers have traditionally focussed on commercial fisheries, but there is now an increasing recognition that harvests taken by recreational fishers can sometimes be considerable, at times exceeding that [...]

Marine recreational fishing is popular in Norway, but current estimates of the catches by resident and tourist anglers are lacking due to several challenges, in particular Norway's long and intricate coastline with no defined access points and the large tourist fishery. To test methods for long-term monitoring of boat-based marine recreational anglers, estimate their catches, and characterize the fishery, we conducted a roving creel survey based on a novel spatial sampling frame and a survey of tourist fishing businesses in Troms and Hordaland County. These surveys showed that cod (Gadus morhua) and saithe (Pollachius virens) dominated the catches in Troms, while mackerel (Scomber scombrus) and saithe dominated the catches in Hordaland. The estimated total annual harvest of cod by all marine recreational anglers was 2 160 tonnes (relative standard error, or RSE 44%) in Troms and 73 tonnes (RSE 29%) in Hordaland, of which ∼40% (in weight) were landed in registered tourist fishing businesses, based on data from the tourist fishing survey. The results indicate that recreational anglers in Hordaland harvest more cod in coastal waters than commercial fishers. This study provides information for developing marine recreational fisheries monitoring in challenging survey situations to support science-based fisheries management. [ABSTRACT FROM AUTHOR]

Intraspecific variation in movement patterns are well established for many species, but poorly appreciated in fisheries management. In this study we dart-tagged snapper (Pagrus auratus), an important fishery species, across different areas and habitats in the Hauraki Gulf, New Zealand. Tag returns were used to quantify movement behaviour and extraction rates using a maximum likelihood model that corrected for spatial variability in population size and fishing effort. Residency was high (~90%) in two strata and lower (75%) in the remaining stratum. The stratum with the highest residency also appeared to experience the highest extraction rate (likely due to a lower population size). These results confirm the existence of differences in movement behaviour within the snapper population, suggesting that localized areas may become depleted regardless of the status of the overall stock. This has consequences for the scale of fisheries management and the size of marine reserves implemented in different regions. Understanding why variation in movement behaviour exists (i.e., genetic vs. environmental) is the next step in addressing the influence of animal behaviour on fisheries management. Les variations intraspecifiques dans les patrons de displacement sont bien connues chez plusieurs especes, mais mal comprises dans la gestion des peches. Dans notre etude, nous avons marque avec des etiquettes a dard des pagres (Pagrus auratus), une espece importante pour la peche commerciale, dans des sites et habitats differents dans le golfe de Hauraki, Nouvelle-Zelande. Les retours d'etiquettes ont servi a determiner le comportement de deplacement et a calculer les taux d'extraction a l'aide d'un modele de vraisemblance maximale qui tient compte de la variabilite spatiale de la taille de la population et de l'effort de peche. Le taux de residence est eleve (~90 %) dans deux des strates et plus faible (75 %) dans la troisieme. La strate avec le taux de residence le plus eleve semble aussi connaitre le taux d'extraction le plus fort (vraisemblablement a cause d'une population plus petite). Ces resultats confirment l'existence de difference de comportements de deplacement dans la population de pagres, ce qui laisse croire que des sites particuliers peuvent devenir depeuples, quel que soit le statut du stock dans son ensemble. Cela a des consequences sur l'echelle de la gestion de la peche et sur la taille des reserves marines etablies dans les differentes regions. La prochaine etape consiste a comprendre pourquoi il existe une variation dans le comportement de deplacement (c'est-a-dire le role relatif des causes genetiques par rapport aux causes environnementales) pour evaluer l'influence du comportement animal sur la gestion des peches. [Traduit par la Redaction], Introduction Intraspecific variation in movement behaviour or partial migration (the existence of both resident and migratory movement patterns within a single species) is well documented (e.g., insects: Schistocerca gregaria (Rainey [...]

The growing awareness of the impact that recreational fishers can have on fish stocks has highlighted the paucity of information used to inform their management. Most of the available information on the scale and nature of recreational catch and effort has come from intermittent and labour‐intensive surveys that provide fragmented insights into often highly variable fisheries. Digital cameras offer a more cost‐effective means of continuously monitoring trends in recreational fishing effort, and it is surprising that greater use of this approach has not been made to date given its widespread use in other contexts. We share lessons learnt from four early adopter studies in New Zealand, Australia and Germany, where digital cameras have been used to monitor recreational fishing effort. Many of the challenges that we have encountered and overcome were initially unforeseen, and we suggest solutions and strategies to address these issues. We conclude that all aspects of a camera‐based monitoring system should be considered from the outset, to optimize the utility and value of the information they provide over the long term. Aspects to consider include the location and configuration of a camera system, ensuring service continuity, image quality, data storage, image interpretation and ultimately the analysis of any data collected. Robustly designed digital camera monitoring systems can be used to gain greater insight into recreational fishery dynamics, leading to more informed, responsive and effective fisheries management. [ABSTRACT FROM AUTHOR]