Overall, trends observed for the immediate pre period were retained for the — period, unless some significant socio-economic changes were noticed or recreational fisheries were known to have changed distinctly after Such changes and improved data are regularly integrated into updated versions of Sea Around Us data at www.
First, we present the results of the four country examples of recreational catch data reconstructions, followed by the global results for all countries or territories based on the methods, data sources and material presented in the Supplementary Materials and associated publications. The estimated total reconstructed marine recreational catches in Brazil increased rapidly from around t in to nearly 1, t in Figure 2. We did not undertake a detailed taxonomic disaggregation of recreational catches for Brazil, as the wide range of ecosystem types along the very long Brazilian coast makes for a large diversity of target species, and local studies with useful catch composition are still too scarce to allow for such estimation.
Figure 2. Total estimated catch from marine recreational fisheries by region in Brazil from to daily recreational fishing activities plus fishing tournaments. Data based on Freire et al. The total estimated marine recreational catches in Angola decreased from around t in to 5 t in at the start of the civil war period following independence Figure 3. During this earlier period, recreational fisheries seemed to focus mainly on Sphyrna spp.
The long period of civil wars, from to , was not conducive to recreational fishing, as reflected in catch amounts close to zero. After , catches increased rapidly to nearly t by Figure 3. Figure 3. Estimated catches by taxon from marine recreational fisheries in Angola from to Data based on Belhabib and Divovich , For the Philippines, reconstructed recreational catch estimates displayed a continuously decreasing trend from around t in to about 52 t by Figure 4.
Medium and large pelagic taxa dominated the catch: Scombridae mackerels, tunas and bonitos , Istiophoridae billfishes , Carangidae jacks and Coryphaenidae dolphinfishes, Figure 4. Figure 4. Derived catch composition of marine recreational fisheries in the Philippines from to Data based on Espedido et al.
The marine recreational catches for the United States were the highest among the four case studies presented here. Recreational catches across the United States that were retained by the fisher i. A second increase to a peak of about , t in followed, before recreational catches again decreased to around , t by Recreational catches were also fairly common on the West Coast in the earlier decades, although they have decreased considerably since the s.
On the other hand, recreational catches around Hawaii have increased considerably since the early s, and now exceed all other areas other than the East Coast Figure 5A. Figure 5. Data based on Zeller et al. The data underlying the US recreational catch reconstruction had the best taxonomic resolution of any data in this study. Throughout the period the most important changes observed were strongly declining catches of Pomatomidae starting in the s and increasing catches of Coryphaenidae dolphinfishes, commonly known as mahi-mahi and Moronidae basses; Figure 5B.
However, regional differences were observed over time: catches have been steadily increasing in Asia, South America and Africa, while catches have been decreasing strongly in North America and less so in Europe and Oceania Australia and New Zealand mainly since the mids Figure 6.
Figure 6. Global marine catches from recreational fisheries by major geographic region for — for all countries with marine recreational fisheries. Data based on Pauly and Zeller a; b , and sources therein. See Supplementary Materials for country details. An examination by major geographic regions Supplementary Figure S1 indicated some similarities, such as Scombridae associated with high catches in five regions, and Sciaenidae and Sparidae in four regions.
Figure 7. Taxonomic composition of global recreational catches by the nine most represented families or higher groupings. Estimating the global catch from marine recreational fisheries is not an easy task, as reporting on this activity is extremely sparse and highly inconsistent within and between countries and over time.
Furthermore, it is sometimes difficult to delimit the boundaries of this activity, as recreational fishing sometimes overlaps with subsistence and artisanal fisheries see Cooke et al.
We found that global recreational catches may average around , tonnes per year in recent years. While not large in terms of tonnage compared to the over million tonnes caught commercially each year Pauly and Zeller, a , recreational fishing has substantial economic impacts through the value adding derived from recreational activities Cisneros-Montemayor and Sumaila, Even though our global estimate of recreational catches is a small fraction of global commercial catches Pauly and Zeller, a , in some regions and for some taxa, recreational catches match or even surpass commercial catches Coleman et al.
A prime example of this is in The Bahamas, where recreational catches exceed the commercial take Smith and Zeller, The time series of global recreational catch estimates for recent years suggests a pattern of gradual increase starting in the s. This is due to a strong increase in recreational catches observed in Asia, and smaller increases in South America and Africa.
Thus, these trends in emerging economies and developing countries sustain a gradual growth in recreational catches even though declines have been observed in North America and Europe, mainly due to decreasing participation rates in highly industrialized regions Bower et al.
Here, we consider a few of the issues encountered when estimating recreational catches, with emphasis on the four case study examples, and which are indicative of issues encountered in most, if not all, country reconstructions for recreational catches. A major challenge we noted during our reconstruction efforts is that many scientists and fisheries experts in developed countries often erroneously assume that recreational fisheries do not exist in many developing countries, for example in West Africa.
Yet, recreational fisheries can exist in even the least developed countries, where they are often associated with international tourism, and their approximate catches can be estimated based on previously unused methods, including YouTube and other social media channels Belhabib et al.
A further issue to be addressed in recreational fisheries and their management is the species and individuals being targeted. Recreational fisheries are often directed toward trophy fishes, which can have considerable impact on the size structure of some stocks, especially if the species is a threatened species Shiffman et al.
Recreational fisheries also increasingly emphasize catch and release as the primary method of recreational fishing Brownscombe et al. Thus, the increasing emphasis on catch and release may account for some of the declines observed in, e. However, catch and release practices can result in significant post-release mortality Cooke and Cowx, , but as data on this activity are generally lacking, we did not attempt to estimate the post-release mortality impacts, except for the U.
Thus, unless the currently insufficiently examined catch and release mortality is consistently high, we assume that our assumption in cases of catch and release was conservative, likely leading us to underestimate both recreational fishing engagement as well as actual mortality caused by recreational fishing.
Regarding the potential sale of recreational catches, this practice is usually illegal in most countries. In countries where the sale of recreational catches is allowed, permission is usually granted only to cover the cost of fishing trips FAO, This clearly blurs the boundaries between non-commercial recreational activities and commercial artisanal fishing.
This has been shown to be particularly problematic in Algeria, where so-called recreational fishing is a smoke screen for hidden commercial activities, leading to substantial economic losses for the society as well as the legitimate commercial fisheries Babali et al. In some cases it is difficult to differentiate recreational from subsistence fishing.
For example, Brazil has a strong consumption-oriented fishing habit see, e. These conflicts are more serious with groups that promote catch-and-release as a management tool Policansky, To illustrate how recreational catches can be considered illegal in some cases, we compared the Philippines with Brazil.
Recreational fisheries in the Philippines include fishes caught by spearfishers, both with and without SCUBA gear, and competitive and non-competitive anglers Espedido et al. Spearfishing is not explicitly stated as being illegal in federal regulations in the Philippines. Rather, it is under the jurisdiction of local governments municipalities. However, as unpublished PCSSD rules and regulations do not carry the same legal weight as federal regulations, spearfishing with or without SCUBA is practiced widely in the Philippines despite being considered illegal.
Thus, unambiguous and consistent legislation is key to setting clear guidelines for acceptable recreational fishing activities, just as they are required for commercial fishing. The uncertainty around catch estimates can be high in the reconstruction process for recreational fishing, especially for earlier years. However, such uncertainty can go both ways.
We consider that our estimates for Brazil are likely underestimates, based on the low recreational participation rates utilized Freire et al. For many Brazilian states, we considered only coastal catch rates i.
The fishing habits of recreational fishers in the seventeen Brazilian coastal states vary; therefore, the taxonomic breakdown is highly variable and uncertain Freire et al. Given the often sparse information on the taxonomic composition of recreational fishing activities in many countries, reconstructed catch estimates by taxon need to be treated as broad approximations and viewed with caution in many cases.
As with commercial fisheries Freire and Pauly, , the widespread use of highly variable common and local names for species is a problem in recreational fisheries. Common names may differ substantially between geographic regions, even within countries, and from the names used by commercial fishers. For this reason, it was often only possible to report estimated catches at the family or higher level of taxonomic resolution to reduce uncertainty in the correspondence between common and scientific nomenclature.
However, this can mask the impact of recreational fisheries on individual populations, such as for individual species of sharks and rays which are often reported only as Elasmobranchii.
Considerable and consistent recreational catches of sharks and rays in South America and Oceania raise concerns, because these groups usually include K-strategy species with slow maturation, low reproductive output and long life histories, which make them more susceptible to overfishing. Actions such as the encouragement and re-direction of recreational shark fishing toward non- or less-lethal fishing Cuevas, may change fishing habits from catch-and-kill to more conservationist approaches, as happened in the U.
On the other hand, the rise of activities such as beach-based trophy shark hunting in countries like the United States Shiffman et al. An issue that also emerges is the nomenclature of organized events such as competition, tournament, jamboree, and championship.
These terms are used often interchangeably, but may have different meanings, and hence different catch ramifications, in different countries. For example, in Brazil, jamboree and tournament are used to indicate events open to the public.
These differences may result in substantially different catch rates and participation rates, and may have considerable impacts on the resulting catch estimates.
Even though in some countries, e. Often, as in the case of the Philippines, such records are not publicly available or may not be recoverable upon request from the responsible government organization. Thus, we were unable to fully compare these events with those occurring in other regions, such as North America, where extensive information is collected Schramm et al.
Importantly, even in cases where governments do have data on recreational catches, e. Figueira and Coleman, , fully scaled-up, country-wide recreational marine catch estimates do not seem to be incorporated into the national fisheries statistics published by these countries, nor are they included by the vast majority of countries in the data they report to FAO but see the exception of Finland Zeller et al.
For the vast majority of countries around the world, however, no such data exist as part of nationally collected and reported datasets as yet. However, there are still a number of countries for which catch data reconstructions did not address or examine recreational fisheries. This may be an additional reason for the global estimate presented here to be a conservative underestimate. The second of these other estimates of In contrast, our approach reconstructs catches independently for each country, before summing these independent estimates for the present global synthesis paper.
We anticipate that this study, and the underlying data freely available at www. After all, ecosystem considerations in fisheries management Pikitch et al. The datasets generated for this study are available on request to the corresponding author. All authors contributed to the writing and editing of the manuscript and approved its submission. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.
We would like to thank all current and former members and external collaborators of the Sea Around Us for helping compile data and undertaking data reconstructions over the last two decades.
We thank recreational fishers for providing local information on recreational fisheries, including results of fishing events; A. Coghlan for preparing the map; and W. Figueira, F. Coleman, P. Kalvass, E. Kraig, D. Ayres, and M. Hunter for providing recreational catch data for the United States. Any information provided by local fishers adhered to the prevailing ethical considerations in the given country, and names and locations were treated as confidential if requested.
Ainsworth, J. Google Scholar. Ontario: Oregon Department of Fish and Wildlife. Anon Records do Mundo de Angola na Pesca Desportiva. Babali, N. Recreational fisheries economics between illusion and reality: the case of Algeria. PLoS One e Barcellini, V. Recreational anglers and fishing guides from an estuarine protected area in southeastern Brazil: socioeconomic characteristics and views on fisheries management.
Ocean Coast. Belhabib, D. Best for pleasure, not for business: evaluating recreational marine fisheries in West Africa using unconventional sources of data. Palgrave Commun. Vancouver: University of British Columbia. Berners, D. Berners London: Wynkyn de Worde.
Bonfil, R. Fowler, T. Reed, and F. Bower, S. Silva, A. Ferreira, and M. Brownscombe, J. Best practices for catch-and-release recreational fisheries — angling tools and tactics. Cashion, T. Fisheries in Somali waters: reconstruction of domestic and foreign catches for Policy 87, — Chadwick, H. This culling preference is different from commercial or subsistence fishing, which aim to catch as many fish as possible, but not necessarily the largest individual member of a species.
The paper looked at the global state of management regulations for recreational fishing and found that only 86 nations define recreational fisheries in their national fisheries-management legislation. Another major issue with recreational fisheries management boils down to numbers — or lack of them.
In most places nobody knows exactly how many fish are caught. They consolidated information from a variety of sources and built a bigger picture. Potts points out that this kind of formulation can cause complications. Even though the results are estimates, they suggest two potentially troubling trends. First, all recreational fisheries catch is significantly increasing in developing-world nations, especially in Africa and South America.
For example, the number of recreational fishing licenses in Brazil jumped from , in to more than , just two years later. As angling can be both commercial and non-commercial, recreational angling can be defined as the activity of catching or attempting to catch fish, principally by rod and line, pole or hand-held line for non-commercial purposes. Recreational angling is a very sustainable kind of fishing compared to other kinds of fishing, commercial as well as recreational, thanks to the low-impact, highly selective catching gear used and the high survival rate of the fish released-.
In many countries recreational fishing generates more value than does commercial fishing. In order to offer the best user experience we use cookies. By the application of harvest slots within a realm of high productivity, fishing mortality becomes a sustainable expansion of natural mortality that leaves enough excess for future generations to persist. The harvest slot furthermore leads to benefits such that fish outgrowing the kitchen window remain in the ecosystem, further developing and releasing their high value for the reproductive success of the population.
Also, from a genetic point of view advantages arise, as the removal of intermediate-sized fish potentially decreases the risks of reducing fish genetic heterogeneity Birkeland and Dayton Finally, for the determination of harvest quotas, Mertz and Myers assume that, if fishing mortality is equal to the natural mortality, at least one half of the production of the stock may be harvested.
Based on the available data Table Half of the yearly net production divided by an average weight of a harvested fish of g results in an average possible sustainable harvest of almost brown trout per year. On average the proposed harvest quota would therefore range between one third to one fourth of the respective stock, which means a sufficient amount of fish remaining to continue and grow bigger, even in years of very low abundance.
That increases the chances of survival for smaller fish, and this extra production again can result in surplus or sustainable production Wallace and Fletcher In summary, the example of the River Ois illustrates the necessity to develop fisheries management approaches on the basis of careful consideration of changing stock quantities. The analysis of quantitative fish data reveals the size and the dynamics that are inherent in the stock and therefore form the basis for management decisions.
Simplified life cycle scheme of brown trout in the catchment of the River Ybbs Ois. The respective fishing beat bold line benefits from immigrating trout. Boxes indicate highest abundance of respective age class within the catchment. A migration barrier dashed line at the lower end of the fishing beat prevents upstream migration. Analysis of the habitat quality to isolate and specify potential bottlenecks. The first step of deficit analysis aims to detect the occurring habitat deficits, which typically are related to hydrological water abstraction, hydropeaking, thermal alterations, etc.
Both types of interventions, but also the retention of bedload in upper reaches of the catchment, can have further negative consequences for the quality of bed sediments and the availability of food. The analysis of habitat quality is intended to serve fisheries management purposes. The main focus is on the habitat requirements of all different life stages of the river-type-specific fish species, clearly highlighting the species relevant for angling and relevant prey fish.
This is in many cases congruent or at least in line with processes of river restoration projects, but the scope of river restoration is generally broader, and fish fauna are just one out of many important aspects related to the ecological integrity of running waters see Chaps.
The starting point for the habitat analysis is set by the life cycle of the fish species of interest. A fish life begins at the spawning ground—therefore the quality of spawning habitats is a major issue and has to be thoroughly analyzed. The most prominent fish species of alpine rivers, such as brown trout, grayling, and Danube salmon, rely on loose gravel for spawning and successful recruitment. Potential spawning habitat deficits are typically related to increased accumulation rates of fine sediments, on the one hand, or to an artificial coarsening of bed sediments on the other hand see Chap.
Increased input of fines leads to clogging of the interstitial pores and consequently degraded gravel beds, hindering redd excavation or the successful development of incubated eggs.
Retention of sediments through torrent control structures and impoundments as well as flushing out gravel due to reservoir management practices lead to coarsening of bed sediments, impeding redd construction for interstitial spawning salmonid species. Overall, alterations of natural sediment regimes are a severe and widespread problem in alpine rivers, and deficits of suitable spawning habitats are consequently among the major bottlenecks in many rivers and streams e.
For example, trout fry develops inside interstitial pores for a period of up to 6 months. Thus, not only the spawning itself but also the early development after hatching is affected by deteriorated riverbeds. Even though eggs are able to develop, high losses can occur in the alevin or early fry stage when sealed river beds prevent juveniles from successfully emerging. Further on in the life cycle, early juvenile stages are threatened by a variety of human-induced, hydrological impacts, such as stranding due to hydropeaking surges see Chap.
Morphological alterations due to damming and other river control measures see Chap. While residual flow stretches mainly reduce the amount of adult fish habitat as the amount of flow and consequently habitats are reduced see Chap. Another major problem is the disruption of migration pathways, both laterally and longitudinally see Chap.
Beside weirs and ramps, riverbed degradation and, consequently, disrupted connections between main stem and tributaries hamper spawning migrations and decrease the original longitudinal range of populations. In addition to hindering upstream migration, specifically hydropower weirs and the associated turbines can cause high mortality of downstream migrating fish. Even this incomplete list of possible habitat perturbations reveals how analyzing habitat quality constitutes a major task of fisheries management.
As the life cycle stages of any fish species are related to distinct habitat features, the quality of these features has to be assessed and contrasted with data on fish demographics and distributions.
In many cases, fish population structures specifically reflect the habitat situation and help identify potential quality shortcomings. The most powerful management action to sustainably support healthy fish populations is habitat restoration.
Consequently, especially for the conservation of wild fish stocks, the primary task of fisheries managers is to pursue all options to restore habitat conditions to as close to a pristine situation as possible.
Small-scaled mitigation measures, such as the maintenance or improvements of spawning grounds e. However, mitigation or restoration at large- or even catchment-scales needs broader efforts see Chap. To attain objectives on a larger scale, fisheries managers dealing with common issues e. Combining a critical mass of expert and public opinion is a vital necessity in Austria, where riverine water bodies are characterized by a small-scale segmentation of management units.
However, when the habitat quality analyses are completed, the results have to be contrasted and merged with the results of step 2, the survey of the current fish stocks. Quantitative electrofishing data must first be generated to enable a comprehensive assessment of the actual population status, e. As highlighted in the Ois example, yearly surveys and long-term data series create the most desirable basis for analysis.
In many cases fish stock data are missing or collected only sporadically. However, it is an important management task to gather stock data. Although the financial expenditure for fish stock surveys is substantial, it will pay off, since in combination with the habitat quality survey potential bottlenecks become detectable. Furthermore, the elimination of habitat deficits will sustainably improve the stocks, as opposed to stocking as a continuous management measure, which generates costs without solving the underlying problems see below.
Further, to have sufficient knowledge on the actual fish populations and habitat quality provides the opportunity to reflect and evaluate preceding management actions, specifically success or failure of stocking campaigns see below. The results of all the three steps of deficit analyses provide the basis for the elaboration of management strategies and to derive management actions.
Fisheries management actions have to be adopted according to the ecological status of a river. However, if habitat problems remain and essential environmental prerequisites for different life stages are lacking, stocking might be the only option to sustain recreational fishing. While compensatory stocking can help to sustain recreational fishing, and can be seen as ecologically reasonable, stocking solely to attract or satisfy anglers can hardly be justified in the context of sound or ecologically orientated fisheries management.
Whenever fishes are stocked, one should account for possible negative consequences for the receiving ecosystems and contrast them with potential benefits mainly socio-ecological.
Economic issues or the benefit of the owners of fishing rights play an important role in Austria, where the right to fish is a private law and profits are part of the income of the respective fishing right holder.
This fact hampers the elaboration and implementation of large-scale, e. Besides the negative impacts that stocked fish might have on wild stocks due to resource competition processes, two further major issues have to be considered: aspects of genetic descent as well as deficits deriving from the artificial propagation in hatchery environments.
Typically, hatchery fish suffer from various abnormalities as they are kept under hatchery conditions for a period of time.
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