Types Of Fishing Gear Research Articles

Effects of spatial–temporal conditions and fishing-vessel capacity on the capture of swimming crabs by using different fishing gear around the waters of Taiwan

Context Swimming crab is a vital fishery resource and a valuable source of income in the southern East China Sea, but it lacks management strategies, especially when using different fishing gear. Aims This study aimed to determine the effects of spatial–temporal conditions and vessel capacity on swimming crabs by using different fishing-gear types in the Taiwan Strait (TS). Methods We used generalised linear mixed models (GLMMs) to investigate data from Taiwanese vessels (2011–2019) on how spatial–temporal conditions and vessel capacity affected the catch of swimming crabs when using trawls, gill-nets and traps. Key results The results showed that the traps (>80.0%) caught more swimming crabs in the TS than did the gill-nets (6.6%) and trawls (8.0%). Additionally, the GLMM analysis showed that Charybdis feriatus, Portunus pelagicus and Portunus sanguinolentus catches by traps and trawls were significantly affected by different fishing locations, climate events, work hours and vessel sizes. However, for gill-nets, spatial–temporal conditions and vessel capacity did not affect the catch of C. feriatus. Conclusions Monitoring fishing efforts and environmental factors is vital to understanding their impacts on marine ecosystems. Implications These findings enable future sustainable crab fishing through harvesting strategy planning, ecosystem management and spatial–temporal governance.

Fishing Gear Pattern Recognition by Including Supervised Autoencoder Dimensional Reduction

Fishing is a crucial worldwide activity as it provides a source of food and economic income. A challenge in ecology and conservation is decreasing overfishing and illegal, unreported, and unregulated fishing (IUUF). One strategy to decrease those issues is to track vessels for detecting fishing behaviors through monitory systems. In this letter, we present an approach to classify fishing behaviors, specifically, for four fishing gear types (trawl, purse seine, fixed gear, and longline) using automatic identification systems (AISs) data from the Global Fishing Watch platform. Thus, our main contribution is how we propose data processing by including a supervised autoencoder dimensional reduction (SA-DR) processing data step. This step allows removing redundant features and noise, avoiding overfitting, decreasing data complexity, and preserving the differences between classes. Specifically, we propose to use IVIS and centroid encoder (CE) methods. The experimental results show how our approach applying SA-DR over the vessel trajectory feature representation reduces the variation results among different classifiers and achieves a high classification accuracy of up to 95%. This result could help prevent IUUF, overfishing, and improve fishery management strategies.

Technical solutions for European small-scale driftnets

Small-scale driftnets provide a high degree of size and species selection, chiefly through their mesh size. The main environmental impact of driftnets is due to the bycatch of non-target species. At present, few alternative methods to catch target species are available, and there is disagreement on the impact of some of them. The aim of the present study is to analyse and review the literature to find and explore alternative technical solutions to a complete ban on European small-scale driftnet fisheries, taking into account the scientific evidence of the damage that driftnets may cause to the environment in the different regions. Environmental impact on non-target species, including protected species, of current small-scale driftnet fisheries is similar to that of other passive fishing gears, such as purse seines, boat seines, trammel nets, set gillnets, and set- and drifting-longlines. Proposals are advanced to reduce the environmental impact of small-scale driftnet fisheries both in terms of conversion to other activities and improvement of selectivity. The study provides recommendations for policymakers to base their decisions on the circumstances in which driftnets use are not acceptable. It examines the effectiveness of mesh size and twine thickness limits of 90 mm and 0.6 mm, respectively in all driftnet fisheries, the restrictions on the fishing gear types and dimensions, and then the possible selective ban on those driftnet fisheries that are more harmful to protected species and/or are unable to avoid unwanted bycatch of unauthorised species.

Fishing-gear restrictions and biomass gains for coral reef fishes in marine protected areas.

Considerable empirical evidence supports recovery of reef fish populations with fishery closures. In countries where full exclusion of people from fishing may be perceived as inequitable, fishing-gear restrictions on nonselective and destructive gears may offer socially relevant management alternatives to build recovery of fish biomass. Even so, few researchers have statistically compared the responses of tropical reef fisheries to alternative management strategies. We tested for the effects of fishery closures and fishing gear restrictions on tropical reef fish biomass at the community and family level. We conducted 1,396 underwater surveys at 617 unique sites across a spatial hierarchy within 22 global marine ecoregions that represented 5 realms. We compared total biomass across local fish assemblages and among 20 families of reef fishes inside marine protected areas (MPAs) with different fishing restrictions: no-take, hook-and-line fishing only, several fishing gears allowed, and sites open to all fishing gears. We included a further category representing remote sites, where fishing pressure is low. As expected, full fishery closures, (i.e., no-take zones) most benefited community- and family-level fish biomass in comparison with restrictions on fishing gears and openly fished sites. Although biomass responses to fishery closures were highly variable across families, some fishery targets (e.g., Carcharhinidae and Lutjanidae) responded positively to multiple restrictions on fishing gears (i.e., where gears other than hook and line were not permitted). Remoteness also positively affected the response of community-level fish biomass and many fish families. Our findings provide strong support for the role of fishing restrictions in building recovery of fish biomass and indicate important interactions among fishing-gear types that affect biomass of a diverse set of reef fish families.

Turtles and other marine megafauna bycatch in artisanal fisheries in the Saudi waters of the Arabian Gulf

Fisheries impacts on marine megafauna have received global attention and are recognized as a serious problem. In Saudi waters of the Arabian Gulf, the artisanal fishery is responsible for 99.6% of landings. It uses a range of boat sizes and various types of fishing gears and operates in all accessible areas from shallow coastal bays to deep offshore waters. The objective of this work is to assess the captures and the impact of all fishing gear types used by the Saudi artisanal fishery on four marine megafauna groups: turtles, birds, dolphins, and dugongs (Dugong dugon). Nine questionnaire surveys were carried out from May 2013 to November 2014, covering a two-month period each. Ten main gear types were found to be used by 25 directed fisheries, including shrimp trawl, wire trap, hand line, troll, pelagic and demersal longline, and drift, surrounding, fixed, and set gillnets. Turtles were captured in relatively high numbers (4726 captures year−1) in nine directed fisheries, among which shrimp trawl fishery was responsible for 86.3% of the captures. The lowest capture rates were found with birds (13.1 captures year−1) and dolphins (7.4 captures year−1), related mainly with the Spanish mackerel longline and Indian mackerel surrounding gillnet fisheries. No dugong captures were recorded. In all, the Saudi artisanal fishery operating in the Arabian Gulf has a high impact on turtles and low impact on birds and dolphins. No impact on dugongs was reported during this study.

The artisanal fishing gears and boats used by the Serinhaém Channel fishing communities of the Camamu Bay in the Environmental Protection Area of Pratigi, São Salvador, Brazil

Event Abstract Back to Event The artisanal fishing gears and boats used by the Serinhaém Channel fishing communities of the Camamu Bay in the Environmental Protection Area of Pratigi, São Salvador, Brazil Rogério Cunha1*, Henry L. Spach2 and Alberto T. Correia1, 2, 3 1 Universidade Fernando Pessoa, Portugal 2 Universidade Federal do Paraná, Brazil 3 Centro Interdisciplinar de Investigação Marinha e Ambiental, Portugal Artisanal fisheries have been receiving an increased level of attention from governmental and academic institutions in Brazil in the last years. However the knowledge about the Brazilian artisanal fishing communities is still scarce. In the region called southern lowlands of Bahia - Brazil, there is the Serinhaém Channel, a north arm of the Bay of Camamu, located in the Environmental Protection Area of Pratigi, a sustainable use conservation unit created by the Brazilian State Government in 1998. Several fishing communities are settled along this area, where an important artisanal fishing activity is conducted in this rich estuarine ecosystem characterized by an extensive area of mangrove. This study aimed to describe the fishing gears used by the fishermen communities of Timbuca, Ilha da Barreta, Rio do Campo, Ilha da Pescaria, and Ituberá City. The types of fish boats and evolutionary processes in this sector were also described. The data were collected through fishermen surveys and field excursions, and showed that the fishing gear types used in this area are mainly traps, nets and hook-and-lines, but it also includes some fishing prohibited methods, such as explosives. The fishing boats also suffered significant developments in the last years concerning the building materials and sources of propulsion. Traditional fishing boats are still in use and it consist of wooden canoes propelled with paddles or a sail. Most modern fishing boats are made of fiberglass and moved using a homemade motor engine, locally known as ''motor de rabeta '. The wide variety of artisanal fishing gears and boats observed in this region should be related to the variety of species caught, namely fishes and crustaceans, and to the need of fishermen to ensure better income for their livelihood as fish food becomes scarce. There is an urgent need to protect the artisanal fisheries which faces many challenges due to the lack of policies, strategies and concrete measures that can support sustainable fisheries production, better organization and improvement of the livelihood of fishing communities. Keywords: Artisanal fisheries, Fish gears, Fishing boats, estuary, museological aspect Conference: XIX Iberian Symposium on Marine Biology Studies, Porto, Portugal, 5 Sep - 9 Sep, 2016. Presentation Type: Poster Presentation Topic: 5. ECOTOURISM, ENVIRONMENTAL EDUCATION AND SCIENCE OUTREACH Citation: Cunha R, Spach HL and Correia AT (2016). The artisanal fishing gears and boats used by the Serinhaém Channel fishing communities of the Camamu Bay in the Environmental Protection Area of Pratigi, São Salvador, Brazil. Front. Mar. Sci. Conference Abstract: XIX Iberian Symposium on Marine Biology Studies. doi: 10.3389/conf.FMARS.2016.05.00201 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 07 May 2016; Published Online: 03 Sep 2016. * Correspondence: MD. Rogério Cunha, Universidade Fernando Pessoa, Porto, Portugal, rogitubera@gmail.com Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract Supplemental Data The Authors in Frontiers Rogério Cunha Henry L Spach Alberto T Correia Google Rogério Cunha Henry L Spach Alberto T Correia Google Scholar Rogério Cunha Henry L Spach Alberto T Correia PubMed Rogério Cunha Henry L Spach Alberto T Correia Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

Fisheries Infrastructure Needs Analysis in Order to Capture Fisheries Development Based on Commodities of South Sumatra Province

Development of capture fisheries in South Sumatra province in decline since the separation of Bangka Belitung province. This area of waters caused by the increasingly narrow. However, the development of fisheries sector still has a big opportunity, especially those based on competitive commodities. This study aimed to analyze the type of capture fisheries yield commodities, type, and allocation to take advantage of superior technology, excellent fish seumberdaya, and calculate the necessary facilities and infrastructure for the development of competitive commodities based fishery in South Sumatera province. Research conducted by survey with some analysis tools such as scoring methods, LGP and fishery facilities needs analysis. Flagship species of fish that can be developed such as prawn, swimming crab, fish and machete-cleaver manyung with superior fishing gear types trammel net, drift gill nets, gill nets and fishing equipment. Fisheries is needed is a means of fishery harbors as many as 10 pieces, as many as 20 fruit shipyards, factories nets one unit and processing 8 units. Addition of TPI as a necessary conclusion of the building where the sale of the landed catch of fishermen. Key Words : Capture Fisheries, Competitive Commodities, South Sumatera Province

Incidental Capture of Juvenile Fish from an Artisanal Fishery in a Coastal Lagoon in the Gulf of California

AbstractFishing gear used in artisanal penaeid shrimp fisheries in the southwestern Gulf of California usually consists of the trawl net, gill net, and suripera net. These net types are known to capture a high quantity of fish bycatch and are likely to cause high levels of juvenile fish mortality. However, juvenile bycatch mortality has not been documented in previous studies. The aim of this work was to study the effect of a local artisanal shrimp fishery on the juvenile fish community in the coastal lagoon of Santa Maria la Reforma, Sinaloa, Mexico. Length at first maturity was estimated for the seven most abundant species; based on this information, a generalized linear model and a Bayesian approach were used to estimate the probabilities of juvenile fish capture for different types of fishing gear. We found that the three net types captured juveniles, even those of species maturing at small lengths, and were likely to impact the recruitment of the analyzed species, as the probability of juvenile capture by the nets ranged from 0.20 to 0.90. However, the species for which sexual maturity was attained at a smaller length were less vulnerable to the fishing gear types analyzed. The gill net and trawl net had the highest probabilities of capturing juveniles in general, whereas the suripera net showed a high probability of capturing juveniles belonging to certain species. Incidentally, the suripera net is the gear used most frequently in the area to catch shrimp.

Studies on the fish catch efficiency of different types of fishing gear in Kaptai Reservoir, Bangladesh

AbstractA comprehensive analysis of the efficiency of different fishing gear in capturing Cyprinidae (major carp) species in Kaptai Reservoir, Bangladesh, was conducted. The catch per unit effort (CPUE) data were collected during a 1‐year survey, covering a total of 493 independent fishing units spread across the four major fishing grounds of the reservoir. The study examines the CPUE and catch composition between months and study sites, and the effects of reservoir water level fluctuations, gear diversity and fish distribution patterns on the fish catches. The mean CPUE for all gear ranged between 2.91 and 30.86 kg unit−1 day−1. Analysis of variance showed significant differences among the fishing gear types. The CPUE differed significantly between months for lift nets, large‐meshed (LM) gill nets, cluster hooks and hand lines. None of the fishing gear exhibited significant differences between sites except for cluster hooks. The CPUE of small‐meshed (SM) seine nets was significantly higher than that of other gear. The reasons for such differences in the fish catches were identified as the choice of fishing places, the net sizes, the number of hooks, lures and baits, water turbidity, wind, waves and rainfall. The CPUE indices for lift nets showed significant variation between months for the Cyprinidae species. A significant variation in catch at the different sites was found for all nets, except SM seine nets. The contribution of the Cyprinidae species showed significant differences between sites only for hand lines. The coefficient of variation of CPUE for fishing nets did not vary much more than 55% (lift net), whereas the highest variation of 49% was recorded for hand lines among the hooks and line. Higher reservoir water levels were followed by reduced CPUEs for the Cyprinidae species and vice versa, whereas the highest water levels corresponded to the higher CPUE for the Clupeidae species.

Effect of Size Selection Within and Between Fishing Gear Types on the Yield and Spawning Stock Biomass Per Recruit and Yield Per Unit Effort for a Cohort of an Idealized Groundfish

A discrete time model was developed to evaluate yield and spawning stock biomassper-recruit and yield-per-unit-effort for a cohort of an idealized groundfish. This fish was characterized as relatively long lived (M = 0.2), slow growing (K = 0.2), with maximum length and weight of 100 cm and 10 kg, respectively, and 50% maturity at a relatively early age of 3 years. The size selection characteristics of trawls and hooks were described by a logistic cumulative distribution function (LCDF) with a range of L50 and steepness values. The size selection characteristics of gillnets and traps were described by a scaled normal probability density function (NPDF) with a range of values for Lopt and the standard deviation. Analysis of isopleth diagrams for yield-per-recruit (YPR) and spawning stock biomassper-recruit (SPR) for both types of selection functions indicated that YPR is maximized when harvesting is directed on a fish length slightly larger than that at which biomass for the cohort of the unfished population is maximized, and at fishing mortality rates of 2 and greater. Under these harvesting conditions, SPR was between 24 and 36% of the unfished condition. At these levels of fishing mortality and L50, the steepness of the LCDF does not affect the cohort YPR, but does significantly affect the SPR. Likewise, at these levels of fishing mortality and Lopt, the standard deviation of the NPDF also does not affect the cohort YPR, but does significantly affect the SPR. Thus, a sharper selection process provides a greater SPR available for production of future cohorts. In contrast, yield-per-recruit-per-unit-effort (YPRPUE) is maximized at fishing mortality values of approximately 0.5, when the age at entry or length of susceptibility to fishing gear is set at the age or length of maximum biomass for the unfished cohort. These results present a dilemma for the fishery resource manager: maximize cohort YPR at fishing mortality values of 2 and greater, with a minimum 65% reduction in YPRPUE, or maximize YPRPUE with a 25% reduction in YPR. However, with compromise, 85% of the maximum YPR can be realized with only a 20% reduction of YPRPUE at a fishing mortality level of 0.75.