A preliminary appraisal of the contribution of recreational fishing to the fisheries sector in north-west Trinidad

Abstract An assessment of the recreational fishery in north-west Trinidad was made by questioning participants about the principal fishing methods used, location of activities, catches, effort and cost of fishing. Surface handline methods (live baiting [à la vive] and trolling) and rod and line (banking) were the most common methods used and were pursued mainly in the summer months (April to August). Total fish landings from the fishery were estimated at 1000 t year^-1, equivalent to about 10% of commercial catches for Trinidad. The principal species caught were kingfish, Scomberomorus cavalla (Cuv.), carite, Scomberomorus brasiliensis (Cuv.), cavalli, Caranx hippos (L.), snappers, Lutjanus spp., and groupers, Epinephelus spp. Many of the fishermen sold their catch to offset the costs of the fishing trip and thus competed with commercial fishermen. Recommendations for monitoring and possibly regulating the fishery through a licensing scheme are made.     

The fishery of the Ea Kao reservoir, southern Vietnam: a fishery based on a combination of stock and recapture, and self-recruiting populations

The present paper describes the fishery of the Ea Kao reservoir in south Vietnam. Historical data on the total production and total numbers of fish stocked were available from 1983 to 1996, and this information, together with the results of monthly monitoring of the fishery from June 1996 to December 1998, was used in the present study. A number of gears are used in the Ea Kao fishery, the most important being gill, lift and integrated nets, and beach seines. The fishery of Ea Kao is based on the annual stocking of advanced fry/early fingerlings of 0.3–1.0-g bighead carp, Hypophthalmichthys nobilis (Richardson), silver carp, Hypophthalmichthys molitrix (Cuvier & Valenciennes) and rohu, Labeo rohita Hamilton, as well as the self-recruiting indigenous species Toxabramis houdemeri Pellegrin and two exotic species, i.e. Nile tilapia, Oreochromis niloticus (L.), and common carp, Cyprinus carpio L. On average, the regularly stocked species contribute to 78% of total production, which has been around 400–450 kg ha⁻¹ in the last few years. The monthly peak catches of stocked species tend to coincide with the rainy season from May to October and the catches of self-recruiting species peak between February and April. A significant relationship ( P < 0.001) exists between the stocking density in year n (SD, n ha⁻¹) and the yield of stocked fish in year n + 1 ( Y , kg ha⁻¹):     

Eutrophication and Recreational Fishing on the Finnish Coast of the Gulf of Finland: A Mail Survey

The Gulf of Finland is one of the most eutrophic areas in the Baltic Sea and is also the main fishing area for more than 150 000 recreational fishermen in Finland. The findings of a mail survey showed that the most important species for the recreational fishery is perch, Perca fluviatilis L. There is no clear evidence that eutrophication has had a harmful effect on the stocks of perch and other species considered important. Heavy fouling of gear, particularly gill nets, is the most acute problem caused by eutrophication to the local recreational fishery. The rapid fouling of passive gear was experienced by 67–86% of all fishermen in the three study areas. A general deterioration in water quality was perceived because only 2–14% of fishermen rated the water quality as excellent. However, a minority of recreational fishermen seem to have adapted or grown accustomed to the deterioration in water quality. Even in the two most eutrophic study areas, 23–31% of recreational fishermen considered that an improvement in local water quality would not benefit their own fishing in any way.     

A socio-economic perspective on gear-based management in an artisanal fishery in south-west Madagascar

Abstract  Artisanal fisheries are important socially, nutritionally and economically. Poverty is common in communities dependent on such fisheries, making sustainable management difficult. Poverty based on material style of life (MSL) was assessed, livelihoods surveyed and the relationship between these factors and fishery data collected using a fish landing study were examined. Species richness, diversity, size and mean trophic level of catches were determined for six fishing gears in an artisanal fishery in south-west Madagascar. There was little livelihood diversification and respondents were highly dependent on the fishery. No relationship was found between poverty and gear use. This suggests that poverty does not have a major impact on the nature of the fishery; however, this study was dominated by poor households, so it remains possible that communities with more variation in wealth might show differences in fishing methods according to this parameter. The fishery was heavily exploited with a predominance of small fish in the catches. Beach seines caught some of the smallest fish, overlapped in selectivity with gill nets and also had the highest catch per fishers. Thus, a reduction in the number of beach seines could help reduce the catch of small fish and the overlap in selectivity among gears.     

Gear-based management of a tropical artisanal fishery based on species selectivity and capture size

The population density, species composition and lengths of fish landed by artisanal fishermen using six types of gear: large and small traps, gill nets, hand lines, spears and beach seines were studied in the multi‐species fishery of southern Kenya. Selectivity and catch composition among gears were determined by studying the species richness, diversity, size and mean trophic level of the catches for each gear type, to develop gear‐based management recommendations for this artisanal reef lagoon fishery. One hundred and sixty‐three reef and reef‐associated species from 37 families were recorded in the catch. Beach seines and small traps accounted for the highest number of fish landed (34–35 individuals per fisherman per day). These gears also caught smaller fish than big traps, spears and gill nets. Beach seines caught the highest number of species (14 ± 7 species per day) while most other gears caught four to five species per day with no differences between gears. Predatory species with a mean trophic level of 3.6 dominated catches from hand lines, while the mean trophic level of the other gears was low and ranged from 2.6 to 2.9 with no differences between the gears. The high diversity and small size of fish caught in beach seines indicates that its selectivity overlapped most with large traps and gill nets. Spears and small traps also showed high similarity in species selectivity and small traps captured the smaller mean size of fish, indicating that they are likely to pre‐empt the resource of spears. Large traps, hand lines and spears catch the largest individuals and the species composition of the catch differed sufficiently such that their selectivity should overlap the least and may, therefore, be the preferred mix of gears. The elimination or reduction of beach seines and small traps should reduce the catch of small fish and overlap in selectivity among the existing gears.     

基于渔捞日志的海阳市流刺网船渔获状况分析

为探明流刺网船的捕捞作业情况,根据海阳市2014—2016年流刺网船的渔捞日志,对流刺网船渔获状况进行了分析,并对近海渔业资源利用动态进行了初步探讨。研究表明:流刺网船分为4种作业类型,分别是A类:交替使用海蜇(Rhopilema esculentum)漂流三重刺网、鲅鱼漂流单片刺网和对虾漂流三重刺网;B类:交替使用海蜇漂流三重刺网、对虾漂流三重刺网和青鳞小沙丁鱼(Sardinella zunasi)漂流单片刺网;C类:交替使用海蜇漂流三重刺网、鲅鱼漂流单片刺网、对虾漂流三重刺网和单拖网;D类:交替使用海蜇漂流三重刺网、对虾漂流三重刺网、青鳞小沙丁鱼漂流单片刺网和单拖网。B类的全年单船日平均渔获量低于同一年的其它3类,C、D两类的全年单船日平均渔获量年间波动较大,C类和D类大部分月份单船日平均渔获量都高于A类和B类。结果显示,不同类型各年常见优势种为海蜇、口虾蛄(Oratosquilla oratoria)和三疣梭子蟹(Portunus trituberculatus),夏季4类作业类型渔获物群落结构相似度较高,A、C类在春季或秋季的部分月份渔获物群落结构相似度高,B、D类在春季和秋季的部分月份群落结构相似度较高。     

Damage by monk seals to gear of the artisanal fishery in the Foça Monk Seal Pilot Conservation Area, Turkey

The present study examines the operational interaction between critically endangered monk seals Monachus monachus and artisanal fisheries in the Foça Pilot Monk Seal Conservation Area, Turkey between 1994 and 2002. One to four permanent researchers collected the data on this interaction during the seal sighting data inquiries. Interviews with the fishermen provided 142 direct interactions with monk seals around the fishing gear. Among these encounters damage to fishing gear, including gill nets (53%), trammel nets (37%), longlines (9%) and a lure (1%) was recorded 90 times. However, no difference was found in damage between gill and trammel nets. Although, the damage inflicted by seals per occasion was found to be substantial (maximum 462.5 USD per occasion), the overall annual economic impact on the artisanal fishery was found to be modest. Limitation in soaking time of nets; long-line use instead of nets in MPAs where monk seals survive; and low interest credits to be given to those fishermen who suffer monk seal damage, are proposed as appropriate management practices.     

Probarbus jullieni and Probarbus labeamajor: the management and conservation of two of the largest fish species in the Mekong River in southern Laos

• 1. Probarbus jullieni and Probarbus labeamajor are two of the largest carps in the Mekong River Basin, each reaching a maximum weight of about 70 kg. P. jullieni is listed in Appendix 1 of the Convention on the International Trade in Endangered Species, and both are listed on the IUCN Red List of Threatened Species, the first as ‘endangered’ and the second as ‘data deficient’.
• 2. Six years of quantitative monitoring of a large‐meshed gill net fishery for Probarbus just below the Khone Falls in Khong district, Champasak province, in southern Laos shows that 78% of the overall catch is comprised of Probarbus, with P. jullieni making up 65% of landings.
• 3. Over the 6‐year period catches of Probarbus declined significantly. However, catch‐per‐unit effort statistics do not indicate that the fishery is in decline, although fishers are convinced that real stock reductions are a large part of the reason for catch declines and decreases in fishing effort.
• 4. A number of ecological and social factors are affecting the number and quality of gill nets in use, the length of fishing seasons, and gill net efficiency, making it difficult to compare catch‐per‐unit effort between years.
• 5. There has been a shift from using large‐meshed gill nets for catching Probarbus to targeting smaller species using gill nets with smaller mesh‐sizes. This is an example of the ‘fishing down’ of a Mekong fish community, in which large long‐lived species are the first to be affected by heavy fishing pressure.

Copyright © 2006 John Wiley & Sons, Ltd.     

Catches of target species and bycatches of an artisanal fishery: The case study of a trammel net fishery in the Portuguese coast

In this work we studied an artisanal fishery targeting mainly soles (Solea senegalensis and Solea solea) and cuttlefish (Sepia officinalis) with trammel nets. Catches of target species, bycatches and discards were studied from October 2004 until August 2005 in the west coast of Portugal. A total of 37 sampling surveys onboard commercial fishing vessels were conducted. The number and weight of individuals of all species caught were registered, as well as the amount discarded and retained by fishermen. A total of 112 species were identified: Scomber japonicus, Chelidonichthys obscura and Callioynimus lyra were the most discarded fishes, corresponding to 28% in weight and 36% in number of discards. Discards represented 22%, in weight, of the total catches, while the amount retained by fishermen for consumption or direct selling was 12%, also in weight. The overall estimate of the annual discards value due to this fishery was ca. 170 tonnes, comprising near 45 fishing vessels. Inconsistencies between the catches recorded onboard and the official landings were detected for the main target species. Some bycatches of species under recovery plans were also found.     

Recent evolution of the fishing exploitation in the Thau lagoon, France

Fisheries activity in the Thau marine lagoon (Mediterranean coast of France) has an old tradition and involves different types of gears (set nets, traps and lines) that are used seasonally with varying frequencies in different areas. A survey of fishing activity, main fishing methods and main commercial species composition in the lagoon was carried out to assess the current fishing effort and seasonal yield. Many important changes in fishing effort and in the most important target species occurred during the last 10 years. A gradual decline in eel, Anguilla anguilla (L.), catches followed by an increase of other commercially-exploited species, particularly the gilthead sea-bream, Sparus aurata L., was observed.     

福建海洋捕捞业近年来的变化与可持续发展

十年来我省拖网、张网作业发展太快，捕捞力已大大超过近海渔场资源的承受能力，造成鱼类资源严重衰退，海捕业经济效益明显下降。解决的根本办法是实行限额捕捞制度，逐步减少拖网和定置渔船数量，围刺钓笼作业也要调整发展，并引导上岸渔民改行从事养殖、加工、休闲渔业及第三产业。     

Gill net selectivity for perch (Perca fluviatilis) in the Szczecin Lagoon, Poland

This paper presents the scientific basis for changes in the minimum mesh size in gill nets, from 28 to 30 mm, introduced by fishery management in Poland to limit the catch of undersized perch (those less than 17 cm total length). Experimental fishing with six different mesh sizes was performed in accordance with commercial fisheries practice. A bi-normal selection curve was fitted to the data by including the between-set variation in the model. The locations of the primary and secondary modes of the bi-normal curve on the transformed length scale (length/mesh) were estimated to be 6.95 and 7.41, respectively. The results indicated that a minimum mesh size in gill nets of 28 mm should be sufficient to ensure a low level of discards as well as protecting the interests of fishermen.     

Comparative analysis of artisanal and recreational fisheries for Dentex dentex in a Marine Protected Area

The common dentex, Dentex dentex (L.), is an iconic marine coastal fish in the Mediterranean Sea. This study was performed in the Bonifacio Strait Natural Reserve (BSNR), (NW Mediterranean Sea). The aims were to: (1) evaluate temporal variation of the artisanal fishing of common dentex (2000–2012); (2) compare and quantify catch rates, fishing techniques and catch composition for artisanal and recreational fisheries, and determine the influence of management measures by both activities; and (3) estimate the production of both artisanal and recreational fisheries. Fishery data were collected from different artisanal fishing surveys (onboard fishing vessels and landings) and recreational fishing surveys (roving). The gears with the highest rates of exploitation were longline (3554 g per 100 hooks) and Trolling (351 g boat^?1 h^?1 ±SE), respectively, for artisanal and recreational fishing. This study showed that catches by both activities were quantitatively higher in partially protected areas than outside them. Production estimations suggest that the recreational fishery contributes significantly to fishing mortality and that it can magnify the negative effects of artisanal fisheries. Specific measures are needed for the sustainable fishery management of common dentex.     

A framework for adaptive gear and ecosystem‐based management in the artisanal coral reef fishery of Papua New Guinea

• 1. Artisanal fishing on coral reefs in Papua New Guinea is an important livelihood activity that is managed primarily at the level of local communities. Pockets of overexploitation exist and are expected to increase with plans for increased commercialization.
• 2. This paper provides a current assessment of the artisanal multi‐species coral reef fishery by examining selectivity of the dominant gear, namely line fishing, spearguns, and gill nets. Each gear has its own strengths and weaknesses in terms of use and conservation of resources, with no clear problem gear.
• 3. The three gears utilize different resources but there was moderate overlap in the species caught, particularly between gill nets and line fishing and marginally between lines and spearguns. Gill nets have the disadvantage of being destructive to coral and the advantage of catching commercial species. Line fishing catches an intermediate number of species but mostly large‐bodied and predatory species that could potentially reduce predation and the mean trophic level of the fishery. Spearguns catch the highest numbers of species, including many non‐commercial and herbivorous fish and could reduce the diversity of fish and encourage algal growth.
• 4. This information could be used in combination with scientific monitoring and traditional ecological knowledge to develop an adaptive management framework that uses local restrictions on the various gears to restore or balance the fishery and ecosystem. Restrictions could be selectively imposed: on gill nets when coral cover is low, line fishing when large‐bodied predators are depleted, and spearguns when biodiversity is reduced and algal abundance high.

Copyright © 2008 John Wiley & Sons, Ltd.     

Fisheries catches and the carrying capacity of marine ecosystems in southern Brazil

The carrying capacity of marine shelf ecosystems in southern Brazil for harvestable species is analyzed by (1) quantifying the amount of available primary production appropriated by fisheries catches, (2) evaluating the trend in the mean trophic level of fisheries, and (3) simulating the ecosystem effects of “fishing down the food web” in an intensively exploited shelf region. Fisheries utilize ca. 27 and 53% of total primary production in the southern and south-eastern shelf regions, respectively. Regional variation in the carrying capacity appropriated by fisheries results from differences in the primary production, catch volume and trophic transfer efficiencies. Overall, fisheries landings do not display a trend of decreasing trophic level with time due to the collapse of the sardine fishery and the recent increasing of offshore fishing for higher trophic level species, mainly tunas and sharks. However, the simulations show that fishing down the food web through fisheries that target small pelagic planktivorous fishes, while at first increasing catches in intensively exploited regions, has the potential of decreasing yields, by interrupting major energy pathways to exploited, high-trophic level species. The consequences of these results to the design of precautionary measures for future fishing policies are discussed.     

Role of small-scale fishing in Kompong Thom Province, Cambodia

ABSTRACT:   Household surveys of small-scale fishing were conducted in Svay Ear and Srey Rangit villages in Kompong Thom Province, Cambodia. Data were collected from 104 of 183 households and 105 of 140 households in Svay Ear and Srey Rangit, respectively. In both villages, almost all households conducted rice cultivation and approximately 75% of them also conducted fishing. Three fishing groups: (i) inside lake; (ii) around lake; and (iii) around village were observed in both villages, according to their main fishing grounds. The inside lake group conduct fishing only in Tonle Sap Lake which is located 30 km away from the villages. The around lake group fish in lakes, marshes and flooded forests adjacent to Tonle Sap Lake, which are more than 5 km from the villages. The around village group collects fish from rice fields and ponds located inside the villages and also in some streams, rivers and lakes adjacent to the villages. The distance to the fishing grounds is less than 5 km from the villages. Most fishing groups were the inside and around lake groups, which occupied 76.0 and 65.7% of Svay Ear and Srey Rangit, respectively. These two groups produced 80.6 and 69.7% of the respective village annual total fish catches. These two groups sold a large portion of their fish catches. Although previous reports indicated that small-scale fishing is for subsistence, present results indicated that small-scale fishing was commercially conducted and fishing was important as an income source.     

Non-commercial invertebrate discards in an experimental trammel net fishery

Abstract  Non-commercial invertebrate discards in an experimental trammel net fishery were studied in relation to selectivity of the gear, depth, soak time and season. Forty experimental fishing trials were carried out over a 1-year period with six combinations of small mesh (100, 120 and 140 mm) inner and large mesh (600 and 800 mm) outer panels. On average, 43.8 ± 12.2 (SD) (individuals 1000 m⁻¹ of net) of non-commercial invertebrates were discarded, accounting for 48% and 65% of the total catch and total discards by numbers, respectively. Within non-commercial invertebrates discards, the six most abundant species by number were Phallusia mammillata (Cuvier) (27.5%), Cymbium olla (L.) (13.0%), Sphaerechinus granularis (Lamarck) (11.3%), Paracentrotus lividus (Lamarck) (10.9%), Astropartus mediterraneus (Risso) (8.2%) and Astropecten aranciacus (L.) (8.1%); Echinoderms (43.1%) particularly important. The highest and lowest discard ratios were found in autumn and winter, respectively. Discards generally decreased with depth, varied considerably in relation to soak time and were not related to mesh size combinations. Trammel nets seem to be the most important gear in terms of ecological impacts on benthic invertebrates compared with other coastal fishing gears and at the depths studied (15–60 m).     

渔业协会、渔村社区组织及其渔业资源管理功能

改革开放以来，随着渔业经济的快速发展，我国的渔业发展面一临着渔业资源严重枯竭、渔业监管困难、渔民收入增长幅度放缓等诸多问题。为此学术界在渔业资源管理方法上提出了许多意见，同时也存在着一些分歧。文章通过理论推演，结合文献数据，探讨了渔村社区组织与我国渔业协会的关系，分析了包括渔业协会在内的渔村社区组织对渔业资源管理的作用，通过对代表性渔业资源管理理论的利弊分析，剖析了渔民协会等渔村社区组织的渔业资源管理职能。同时指出由于渔业协会在资源管理中具有重要作用，但因其自身也存在着一定局限性，因此，培育渔业协会、完善其资源管理职能，实行基于渔业协会等渔村社区组织的合作管理也就成为我国加强渔业资源管理的一种制度选择。     

浅析当前近海捕捞渔民用工荒现象

近海渔民用工荒问题是渔业现代化建设中遇到的新问题,是渔民转产转业的附带问题.本文通过对部分省市出现的渔民用工荒现状进行分析,指出了出现该问题的主要原因,认为中国人口大背景及新经济形势、海洋捕捞业的特殊性、传统渔民观念问题以及信息的不对称因素是形成当前近海渔民用工荒问题的主要原因.在文章的最后,给出了相应的对策建议,认为政府应针对性出台并完善具有执行力的扶持政策、船东应放宽眼界扩充外来雇工渠道、大力发挥第三方机构——渔业行业协会等中介组织的积极作用.     

Major difference in mercury concentrations of the African big barb, Barbus intermedius (R.) due to shifts in trophic position

Abstract –  The African big barb ( Barbus intermedius , R.) from Lake Awassa, Ethiopia is an important fish species, especially with the ongoing decline of the Nile tilapia ( Oreochromis niloticus , L.) fishery. Their diet and habitat use was studied using stomach content analyses, stable nitrogen and carbon isotopes, and transect netting. Mercury biomagnification was also determined. The big barb was found to primarily exist in the littoral habitat, with molluscs being their predominant food item. The proportion of small fish ( Barbus paludinosus , P.) in the big barb diet tended to vary somewhat with size, with the largest fish tending to have the most piscivorous diet. Mercury concentrations in the big barb ranged from 0.01 to 0.94 mg·kg⁻¹, and were positively related with size. Fish transects and stable isotope analyses suggest that there may be two feeding forms of big barb in Lake Awassa, with some larger fish preying upon fish (and accumulating higher mercury concentrations). With the declining Nile tilapia fishery in Lake Awassa, the implication of fishermen focusing on large big barb, with its associated higher Hg burdens, is significant with human health ramifications.