In 1988, the red snapper fishery in the Gulf of Mexico was declared severely overfished. Since then, the daily bag limit has been reduced from 7 to 2, the minimum size limit has increased from 13 to 16 inches, and the year-round recreational season has been reduced to one lasting 53 days. Despite NOAA's recommendations that the Gulf States match these regulations, Texas has enforced a 4 bag limit and no seasonal restrictions. In 2009 alone, the total recreational catch exceeded the allocated quota by 1.7 million pounds. The lack of consistency between state and federal regulations and the drastic changes in management schemes have affected anglers' confidence in management, and limited the ability of the fishery to successfully adapt. This study provides an innovative assessment that measures fishers' knowledge and determines their support for current fishery regulations and for the scientific rationale behind the regulatory system. Over 150 interviews of red snapper anglers at charter and head boat docks were conducted along the Texas coast. The majority of respondents were 20-50 year old (74.5%), male (89.3%), four-year college graduates (34.9%), who resided near the coast (65.3%), and were targeting red snapper (92.5%). Results showed that 72.5 percent of respondents agree with the science behind red snapper management, 63.4 percent believe that the stock has improved since 2008, 89.5 percent agree that a bag limit in general is an appropriate management tool, and 78.2 percent agree with the Texas state management of red snapper. However, 51.7 percent of respondents disagree with the federal management of red snapper, and 90.1 percent of all respondents did not know that red snapper live to be 41-60 years old. The lack of support for the federal management may be due to the lack of knowledge of red snapper life span. Applications of this research will be imperative for managers - who already address biological, ecological, and economic aspects of a fishery - to expand their multi-disciplinary approach to include social analysis for the successful evolution of recreational fisheries management. Future research should explore improved management approaches that involve greater communication between the stakeholders and managers.

Atlantic billfish include sailfish (Istiophorus platypterus), blue marlin (Makaira nigricans), white marlin (Kajikia albida, formerly Tetrapturus albidus) and the spearfishes (Tetrapturus); these fishes are found in tropical and subtropical waters. The spearfishes include the longbill spearfish (T. pfluegeri), the Mediterranean spearfish (T. belone) and the roundscale spearfish (T. georgii). The International Commission for the Conservation of Atlantic Tunas (ICCAT) is the regional fishery management organization that conducts research to determine the condition of tuna and billfish resources and supports international cooperative management. ICCAT has determined that blue marlin and white marlin are overfished; the status of sailfish and spearfish are unknown, but overfishing is thought to be occurring. Management of these resources is complicated by uncertainty in the biological models, but uncertainty about the fishers who target these resources. This dissertation studied artisanal fishing fleets that target Atlantic billfish in Venezuela and Ghana, as well as studied recreational charter boat fishing fleets in South Florida and Senegal. The information from these fleets was used to develop performance indicators that evaluate the socioeconomic performance of these fleets. An allocation model was developed to determine the optimal allocation of billfish resources among recreational and artisanal fishers in Ghana, West Africa. Finally, the issues and challenges of managing Atlantic billfish were identified as well as a possible future framework. Results indicate that performance indicators can be used to contrast fleets with different operational objectives. Fishers do produce positive fishing profits in both artisanal and recreational fleets; however, Senegalese recreational anglers are particularly sensitive to fuel costs. Results of the allocation model suggest that the artisanal sector should be allocated 95% of the quota in Ghana. There is the possibility to over-allocate quota to the recreational sector due to methodological differences in determining benefit f and the practice of catch-and-release. ICCAT's limited purview over socioeconomics was identified as the major impediment to effective billfish management. Therefore, it is recommended that the institutional structure for billfish management be modified to include socioeconomic issues, most especially strengthening the link to local institutions in fishing communities.

Over recent decades recreational fisheries have grown substantially throughout the world. Despite this increase, catches from recreational fisheries have often been ignored in fisheries management, although this is now being remedied. Monitoring recreational fisheries can be expensive, and the primary means used for monitoring is angler (creel) surveys, typically funded from sales of fishing licences. The studies presented in this thesis examine different approaches to monitoring recreational trolling fisheries’ catch and effort, where fishing licenses are not required and there are no reporting requirements. I present results from a complemented roving/mail-in survey undertaken during 2013-2014 to estimate recreational effort and catch of Atlantic salmon (Salmo salar) and brown trout (S. trutta) in the largest lake in the European Union, Lake Vänern, Sweden. I also evaluate different angler catch reporting methods (mail-in, tournament reports and face-to-face interviews) and compare catch rates within and among spring and fall fishing periods. In addition, mail-in survey data are examined for recall bias.   I estimate that 28.7 tonnes of salmon and trout combined were harvested by the recreational trolling fishery in 2014, more than the commercial and subsistence fisheries combined. Seasonal differences in both recreational effort and catch were observed. Effort, in boat hours, was significantly higher in spring than in fall. Catch rates of trout were higher in fall than in spring, but there were no seasonal differences in catches of salmon. Harvest per boat day did not differ significantly among catch reporting methods, indicating that all three methods could be useful for managers interested in harvest rates. In contrast, total and released catch per boat day differed among reporting methods, with tournament anglers catching more fish in total. Finally, there was little evidence for recall bias in mail-in surveys, indicating that mail-in surveys are useful for collecting unbiased catch data. My study is the most comprehensive angler survey to date for Lake Vänern, and my results should be of immediate use to local fisheries managers and should also be of interest to researchers and managers interested in estimating catch and effort for fisheries at large spatial scales. / Over the past several decades recreational fisheries have grown substantially throughout the world. Until recently, however, recreational catch has been ignored in the management of many important fisheries. The studies presented in this thesis examine different approaches to monitoring recreational trolling fisheries’ catch and effort in Lake Vänern, Sweden, the largest lake in the European Union. Paper I presents results from a complemented roving/mail-in survey, designed to estimate recreational effort and catch of Atlantic salmon (Salmo salar) and brown trout (S. trutta). The results show that the recreational trolling fishery today harvests more salmon and trout annually than the commercial and subsistence fisheries combined, and that there are seasonal patterns in effort and catch. Paper II evaluates different angler catch reporting methods (mail-in, tournament reports, and face-to-face interviews), compares catch rates within and among spring and fall fishing periods and examines mail-in data for recall bias. Harvest per boat day did not differ significantly among catch reporting methods, indicating that all three could be useful for estimating harvest rates. However, tournament anglers had higher rates for released catch. Finally, there was little evidence for recall bias in mail-in surveys. In summary, this thesis has developed the framework for a recreational angler survey program for Lake Vänern, and should be of interest to researchers and managers interested in estimating catch and effort for fisheries at large spatial scales.

Abstract: Recreational fishing is one of popular outdoor activities and a growing business in Sweden. However, preceding researches had shown that recreational fisheries may contribute to overfishing as much as commercial fisheries. One of the ways to reduce anglers’ impact on fish populations is the practice of releasing caught fish (catch and release; C&R). C&R is often seen as an ethical and sustainable way of fishing that supports fish conservation. Anglers may obtain C&R information and guidelines from different sources, such as fishing club, fishing magazines, state agencies. As the internet is increasingly becoming an important source for anglers to obtain updated fishing information, fishing tourism operators could be a principal actor to provide C&R information and guidelines through their websites. At the same time there is lack of information on the presence and quality of C&R information at Swedish websites. As international tourists are important group of anglers that use tourism operators’ services, and due to the language limitation of the author, this study focused on websites in English language. Therefore, this study aimed at investigating the presence and quality of C&R information and guidelines in English language provided by fishing tourism operators’ websites in Sweden. The study followed the quantitative content analysis approach by assigning categories and counting the frequencies in the text found on the fishing tourism operators’ websites. First, the websites were scanned to check if C&R information was present. Then, the number of clicks needed to retrieve this information was counted to measure its accessibility. Finally, a C&R information quality score was calculated by adding up scores based on different type and quality of the information found on the websites, including 12 criteria of the C&R best practice guidelines developed by Sims and Danylchuk (2017). The study found that 66 out of 151 analyzed websites provided C&R information and guidelines which generally easily  accessed (two clicks on average). However, in general the websites had a low average quality score of the C&R information and guidelines. Moreover, there was a high variability in how the information was presented on the websites, suggesting lack of standardized guidelines that fishing tourism operators could refer to. Consequently, there is a need to encourage and support more fishing tourism operators to provide a high quality C&R information and guidelines on their websites.

Um die Angelfischerei wirksam zu bewirtschaften, müssen Forscher und Manager das Verhalten von Anglern im Kontext einer Vielzahl von Quellenverstehen. Die Angler selbst sind eine heterogene Gruppe, und ihr Wirkungsspektrum ist sehr divers mit vielen sozialökologischen Berührungspunkten. Ziel meiner Dissertation war es, die Zufriedenheit von Anglern, die eine wichtige Rolle bei der angelfischereilichen Bewirtschaftung spielt, und das Verhalten von Anglern im Zusammenhang mit unterschiedlichen Quellen zu untersuchen. Dafür habe ich zunächst eine Meta-Analyse zur Zufriedenheit von Anglern durchgeführt, um ihre fang- und nicht fangbezogenen Mediatoren zu bestimmen. Die aggregierten Effektgrößen zeigten, dass fangbezogene Komponenten (d. h. Fangrate, Größe des größten gefangenen Fisches) stärker mit der Zufriedenheit der Angler zusammenhängen als nicht fangbezogene Komponenten (z. B. Umweltqualität). Im Anschluss an die Meta-Analyse nutzte ich vorhandene Angler-Tagebuchdaten aus unterschiedlichen sozial-ökologischen Kontexten in Deutschland, um zu untersuchen, wie Fangzufriedenheit und „catch & release“ Verhalten variieren und wie sie durch situative und sozial-ökologische Merkmale moderiert werden können. Diese Untersuchung ergab, dass die Bedeutung von Fangergebnissen für die Zufriedenheit je nach Anglertyp (d.h. Spezialisierung des Anglers), Situation und sozial ökologischem Kontext variiert. In ähnlicher Weise fand ich heraus, dass auch das Fangverhalten je nach den genannten Quellen der Vielfalt erheblich variiert. Insgesamt untermauert meine Doktorarbeit die These, dass Forscher im Bereich der Angelfischerei die Vielfalt der verschiedenen Anglertypen, situativen und sozial-ökologischen Kontexte berücksichtigen müssen. Managemententscheidungen, die diese Quellen der Vielfalt nicht berücksichtigen, können Fischereimanager zu falschen Entscheidungen motivieren oder das Vertrauen in die Forschung zu menschlichen Dimensionen in der Freizeitfischerei schwächen. / To manage recreational fisheries effectively, researchers and managers must understand angler behaviour across multiple sources of diversity. Anglers themselves are a heterogeneous group, and they interact with a diversity of fishing opportunities across a diversity of social-ecological contexts. The objective of my dissertation was to study angler satisfaction, a key consideration in the management of recreational fisheries, and angler behaviour across these sources of diversity. First, I performed a meta-analysis of angler satisfaction to study the catch and non-catch related determinants of recreational angler satisfaction. The aggregated effect sizes revealed that catch-related (i.e., catch rate, size of largest fish caught, fish harvested) components were more strongly related to angling satisfaction than non-catch related components (e.g., environmental quality). Following the meta-analysis, I used existing angler diary data from contrasting social-ecological contexts in Germany to explore how catch satisfaction and catch & release behaviour varied, and how they may be moderated by situational and social-ecological characteristics. This research revealed that the importance of catch outcomes towards catch satisfaction varied across angler types (i.e., angler specialization), situational, and social-ecological contexts. Similarly, I found that harvest behaviours also varied significantly across these sources of diversity. Altogether, my doctoral research supports the assertion that recreational fisheries researchers need to account for diversity across angler types, situational contexts, and social-ecological contexts. Work that fails to account for these sources of diversity will have the potential to mislead fisheries managers or reduce faith in human dimensions research within recreational fisheries.

Die Freizeit- bzw. Angelfischerei ist ein komplexes sozial-ökologisches System, welches sich aus drei wesentlichen Komponenten zusammensetzt: einer biologischen, einer sozialen und einer Managementkomponente. Fischereimanager sind aufgefordert, anglerischen Interessen und den Anforderungen einer biologisch nachhaltigen Gewässerbewirtschaftung gleichsam gerecht zu werden. Unzureichend verstandene Wechselwirkungen zwischen den Fischereikomponenten limitieren die Möglichkeit, die Angelfischerei nachhaltig zu entwickeln. Diese werden beeinflusst von lebensgeschichtlichen Parametern der jeweiligen Fischart, von Dynamik und Diversität der Angler sowie von Maßnahmen und Managementzielen. Die Dissertation untersuchte die Bedeutung einer gleichzeitigen Berücksichtigung der drei Fischereikomponenten und ihren Wechselwirkungen zur Realisierung einer biologisch und sozial nachhaltigen Angelfischerei. Ein neuartiges bioökonomisches Simulationsmodell identifizierte Bewirtschaftungsmaßnahmen, die den von der Fischerei erzeugten sozialen Nutzen maximieren. Die Ergebnisse widerlegen die Annahme der Selbstregulationsfähigkeit der Angelfischerei. Die Höhe und Art der Befischungsintensität sowie der soziale Nutzen wurden stark durch eine Vielzahl von fangabhängigen und fangunabhängigen Attributen beeinflusst, wobei auch Anglertyp und Anfälligkeit der Fischpopulation zur Überfischung eine Rolle spielten. Einige Regularien zur Erreichung der Bewirtschaftungsziele waren effektiver als andere, aber ihre Wirksamkeit könnte durch die Haksterblichkeit und die Nichteinhaltung von Vorschriften unterlaufen werden. Obwohl sich die Bewirtschaftungsmaßnahmen je nach Zielart, Anglerschaft und Bewirtschaftungszielen richten, beinhalten die als optimal identifizierten Maßnahmen in fast allen Fällen eine biologische nachhaltige Bewirtschaftung. Die Ergebnisse zeigen, dass ein interdisziplinärer Ansatz zu einer sozial und biologisch nachhaltigen Bewirtschaftung der Freizeitfischerei beitragen kann. / Recreational fisheries are complex social-ecological systems, and managers often need to balance the interests of the anglers utilizing the fishery – the social sustainability – and the biological sustainability of the fish population. However, a poor understanding of the interactions among the main components of a fishery – the biological, social, and management components – has limited our ability to manage recreational fisheries sustainably. Fish life-history type (LHT), the dynamics and diversity of the angler population, angling regulations and management objectives all influence management outcomes. Using both empirical and theoretical studies, I evaluated the importance of jointly considering these primary drivers and the feedbacks between fishery components when managing recreational fisheries. I developed a novel bioeconomic modelling framework to determine which regulations (effort regulations and minimum-size limits) maximized the social welfare derived from the fishery, the optimal social yield (OSY). My research refutes the hypothesis that anglers are self-regulating (i.e., stop fishing when catch rates decline). The amount and type of fishing pressure the fishery received and the social welfare derived were strongly influenced by multiple fishery attributes and differed with the type of angler fishing and the fish population’s vulnerability to overexploitation (LHT). I found regulations influenced fishing mortality rates, but also directly influenced angler behaviour. Some regulations were more effective than others at achieving management objectives, but their effectiveness could be undermined by hooking mortality and regulatory noncompliance. Despite differences in optimal regulations, an OSY management approach generally did not result in overfishing. My research demonstrates that a multidisciplinary approach based on clear objectives can help us progress towards both socially and biologically sustainable management of recreational fisheries.