Assessment of a small-scale fishery: Lane Snapper (Lutjanus synagris) using a length metric method

Small-scale fisheries are hard to assess because of the limited availability of data. Therefore, a method requiring easy-to-obtain catch-data is important for the assessment and management of small-scale fisheries. The objective of this study was to assess the effect of fishing gear selectivity on a length-based metric method proposed by Froese by estimating three indicators using catch-data from Lane Snapper (Lutjanus synagris) collected in Honduras. These indicators are (1) the percentage of mature individuals in the catch, (2) the percentage of fish within the range of estimated optimal lengths to be captured, and (3) the percentage of fish larger than the optimal length. These indicators determine the level of overfishing. The indicators were estimated separately for catch-data corresponding to gill nets, and each indicator was estimated with and without selectivity correction. Selectivity and mesh sizes of the fishing gear had a major impact on the estimation of indicators 1 and 2. As for indicator 3, it consistently showed a high level of exploitation. The three estimated indicators suggested that the Lane Snapper fishery in Honduras is experiencing overfishing. Overall, the method appears to be promising for the assessment of small-scale fisheries, but it should be used cautiously.

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Assessment of a small-scale fishery: Lane Snapper (Lutjanus synagris) using a length metric method

10.1101/2020.05.13.093856 ◽

2020 ◽

Author(s):

Liliana Sierra Castillo ◽

Masami Fujiwara

Keyword(s):

Small Scale ◽

Fishing Gear ◽

Optimal Length ◽

Limited Availability ◽

Small Scale Fisheries ◽

Catch Data ◽

Gear Selectivity ◽

Fishing Gear Selectivity ◽

High Level

ABSTRACTSmall-scale fisheries are hard to assess because of the limited availability of data. Therefore, a method requiring easy-to-obtain catch-data is important for the assessment and management of small-scale fisheries. The objectives of this study were to assess the effect of fishing gear selectivity on a length-based metric method proposed by Froese by estimating three indicators using catch-data from Lane Snapper (Lutjanus synagris) collected in Honduras. These indicators are (1) the percentage of mature individuals in the catch, (2) the percentage of fish within the range of estimated optimal lengths to be captured and (3) the percentage of fish larger than the optimal length. These indicators determine the level of overfishing. The indicators were estimated separately for catchdata corresponding to gillnets, and each indicator was estimated with and without selectivity correction. Selectivity and mesh sizes of the fishing gear had a major impact in the estimation of indicators 1 and 2. As for indicator 3, it consistently showed a high level of exploitation. The three estimated indicators suggested that the Lane Snapper fishery in Honduras, is experiencing overfishing. Overall, the method proposed by Froese appears to be promising for the assessment of small-scale fisheries, but it should be used cautiously.

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A Review on Ray Capture According to Fishing Gear Worldwide

Jurnal Ilmiah Perikanan dan Kelautan ◽

10.20473/jipk.v13i1.24703 ◽

2021 ◽

Vol 13 (1) ◽

pp. 68

Author(s):

Nur Arina Hayati Mohidin ◽

Sukree Hajisamae ◽

Mazlan Hashim ◽

Nik Aziz Nik Ali ◽

Mohd Fazrul Hisam Abd Aziz

Keyword(s):

Coral Reef ◽

Large Scale ◽

Bottom Trawl ◽

Purse Seine ◽

Small Scale ◽

Fishing Gear ◽

Artisanal Fishery ◽

Gill Nets ◽

Small Scale Fisheries

HighlightRay capture worldwide using variety fishing gear.Efficiency of fishing gear used in capture ray species among countries.The maturation size for female and male ray according to species present.Bycatch issues of elasmobranch in small and large scale fisheries.Suitable fishing gear to capture ray species at particular country.AbstractA coral reef is one of the important ecosystems. However coral Gillnets are usually used as a fishing gear by an artisanal fishery in Malaysia. This gear is commonly used by most countries. This paper discussed the rays capture worldwide by using a variety of fishing gear and also bycatch issues that commonly happen. The efficiency of the fishing gear used in capture ray species is compared and discussed among the countries. This paper distinguishes the maturation size for the female and male ray according to the species presence. The bycatch scenario is also discussed as the majority of this elasmobranch (shark and ray) which is caught as bycatch in both small scale fisheries (gill nets, long lines and hooks) and large scale fisheries (bottom trawl and purse seine). This paper explains the suitable type of fishing gear to use to capture ray species in a particular country.

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Strategies of the small-scale fisheries on the Central Amazon floodplain

Acta Amazonica ◽

10.1590/1809-43922002321108 ◽

2002 ◽

Vol 32 (1) ◽

pp. 101-108 ◽

Cited By ~ 2

Author(s):

Carlos Edwar de Carvalho FREITAS ◽

Vandick da Silva BATISTA ◽

Antonio José INHAMUNS

Keyword(s):

Hydrological Cycle ◽

Small Scale ◽

Good Tool ◽

Central Amazon ◽

Small Scale Fisheries ◽

Fisheries Resources ◽

Patterns Of Use ◽

Target Fish ◽

Catch Composition ◽

High Level

A multivariate approach was applied to data of small-scale fisheries developed in Central Amazon, using information about catch composition, environment, fishing gear and season of the hydrological cycle. The correspondence analysis demonstrated to be a good tool for the analysis related multispecies fisheries. The analysis identified patterns of use of fisheries resources by the riverine communities, showing the correlation between the environmental factors and the fishing strategy for the capture of target fish species, indicating the high level of empiric knowledge about the environment and fisheries.

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Discard Avoidance by Improving Fishing Gear Selectivity: Helping the Fishing Industry Help Itself

The European Landing Obligation ◽

10.1007/978-3-030-03308-8_14 ◽

2018 ◽

pp. 279-296 ◽

Cited By ~ 4

Author(s):

Finbarr G. O’Neill ◽

Jordan Feekings ◽

Robert J. Fryer ◽

Laurence Fauconnet ◽

Pedro Afonso

Keyword(s):

Fishing Gear ◽

Fishing Industry ◽

Gear Selectivity ◽

Fishing Gear Selectivity

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OVERFISHING AND OVERCAPACITY SMALL SCALE FISHERIES IN SEMARANG CITY

Jurnal Ilmu dan Teknologi Kelautan Tropis ◽

10.29244/jitkt.v11i2.24817 ◽

2019 ◽

Vol 11 (2) ◽

pp. 427-435

Author(s):

Jamaludin Malik ◽

Achmad Fahrudin ◽

Dietriech Geoffrey Bengen ◽

Taryono Khodiron

Keyword(s):

Sustainable Management ◽

Maximum Sustainable Yield ◽

Utilization Rate ◽

Small Scale ◽

Fishing Gear ◽

Catch Per Unit Effort ◽

Small Scale Fisheries ◽

Surplus Production ◽

Capacity Level ◽

The Status

Fisheries in Semarang City are dominated by small-scale fisheries. This is indicated by the use of the largest fishing fleet of 10 gross tons operating near the coast. This study aims to analyze the status of small-scale fisheries in Semarang City for sustainable management. Sustainable management is management that guarantees the availability of natural resources and environmental services for future generations. The study was conducted for three months, namely September-November 2018 in the coastal waters of Semarang City, which was part of the Fisheries Management Region (WPP) 712. The method used in this study is the analysis of time series surplus production, namely data from the catch (ton/year) and the number of fishing gear (unit) within 10 years (2007-2016), to calculate the catch per-unit effort (CPUE), maximum sustainable yield (MSY), optimum effort (fopt), utilization rate (TP) and capacity level (TK). This study was obtained results of a downward trend in CPUE; the existing fishery catch or production in 2016 has exceeded the MSY value is 479 tons/year (Schaefer) and 439.11 tons/year (Fox); utilization rate of more than 100% which is 108-127% (Schaefer) and 118-138% (Fox), so that small-scale fisheries in Semarang City are at the level of over-exploited. Based on the fopt analysis, the number of fishing gear used (fexisting) has exceeded the optimum effort with a fishing capacity exceeding 100%, so that small-scale fisheries in Semarang City have experienced overcapacity.

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Fishing Gear Selectivity in the Rationalized Aleutian Islands Golden King Crab Fishery

10.4027/fbgics.2015.14 ◽

2015 ◽

Author(s):

D Pengilly ◽

V Vanek ◽

MSM Siddeek

Keyword(s):

Aleutian Islands ◽

Fishing Gear ◽

King Crab ◽

Gear Selectivity ◽

Fishing Gear Selectivity

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Inferring genetic connectivity in real populations, exemplified by coastal and oceanic Atlantic cod

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1800096115 ◽

2018 ◽

Vol 115 (19) ◽

pp. 4945-4950 ◽

Cited By ~ 1

Author(s):

Ingrid Spies ◽

Lorenz Hauser ◽

Per Erik Jorde ◽

Halvor Knutsen ◽

André E. Punt ◽

...

Keyword(s):

Genetic Differentiation ◽

Population Size ◽

Extreme Values ◽

Atlantic Cod ◽

Genetic Connectivity ◽

Fishing Gear ◽

The North ◽

Empirical Estimates ◽

Gear Selectivity ◽

Fishing Gear Selectivity

Genetic data are commonly used to estimate connectivity between putative populations, but translating them to demographic dispersal rates is complicated. Theoretical equations that infer a migration rate based on the genetic estimator FST, such as Wright’s equation, FST ≈ 1/(4Nem + 1), make assumptions that do not apply to most real populations. How complexities inherent to real populations affect migration was exemplified by Atlantic cod in the North Sea and Skagerrak and was examined within an age-structured model that incorporated genetic markers. Migration was determined under various scenarios by varying the number of simulated migrants until the mean simulated level of genetic differentiation matched a fixed level of genetic differentiation equal to empirical estimates. Parameters that decreased the Ne/Nt ratio (where Ne is the effective and Nt is the total population size), such as high fishing mortality and high fishing gear selectivity, increased the number of migrants required to achieve empirical levels of genetic differentiation. Higher maturity-at-age and lower selectivity increased Ne/Nt and decreased migration when genetic differentiation was fixed. Changes in natural mortality, fishing gear selectivity, and maturity-at-age within expected limits had a moderate effect on migration when genetic differentiation was held constant. Changes in population size had the greatest effect on the number of migrants to achieve fixed levels of FST, particularly when genetic differentiation was low, FST ≈ 10−3. Highly variable migration patterns, compared with constant migration, resulted in higher variance in genetic differentiation and higher extreme values. Results are compared with and provide insight into the use of theoretical equations to estimate migration among real populations.

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