scholarly journals DNA barcoding reveals overlooked shark and bony fish species in landing reports of small-scale fisheries from northern Peru

2021 ◽  
Vol 35 (2) ◽  
Author(s):  
Alan Marín ◽  
Renato Gozzer Wuest ◽  
Jorge Grillo-Nuñez ◽  
Irina Alvarez-Jaque ◽  
Juan Carlos Riveros
Keyword(s):  
Dna Barcoding ◽  
Fishery Management ◽  
Stock Assessment ◽  
Species Level ◽  
Bony Fish ◽  
Small Scale ◽  
Shark Species ◽  
Species Determination ◽  
Small Scale Fisheries ◽  
Northern Peru

Species-level identification of commercially landed fish provides pivotal information for stock assessment and fishery management. However, there is a common lack of species determination in landing records from small-scale fisheries (SSFs) worldwide. Using DNA barcoding analyses, we detected four overlooked bony fish (yellow snapper, union snook, blackspot wrasse, and steeplined drum) and one shark species (the sicklefin smooth-hound) in official landing records of SSFs from northern Peru. Of particular concern is the sicklefin smooth-hound shark Mustelus lunulatus that was found to be overlooked and could mistakenly be landed as the humpback smooth-hound M. whitneyi. Increased efforts should be made to improve species identification capacities in Peruvian fishing landings. There is an urgent need to quantify the catch levels of members of the genus Mustelus to species level. This would contribute to a better understanding of the levels of exploitation in each particular species and to improved management decisions.

scholarly journals Using pingers to reduce bycatch of small cetaceans in Peru's small-scale driftnet fishery

Oryx ◽  
2013 ◽  
Vol 47 (4) ◽  
pp. 595-606 ◽  
Author(s):  
Jeffrey C. Mangel ◽  
Joanna Alfaro-Shigueto ◽  
Matthew J. Witt ◽  
David J. Hodgson ◽  
Brendan J. Godley
Keyword(s):  
Large Scale ◽  
Small Scale ◽  
Marine Fauna ◽  
Incidental Capture ◽  
Small Scale Fisheries ◽  
Control Sets ◽  
Northern Peru ◽  
Catch Rates

AbstractThere is growing awareness that small-scale fisheries may have large impacts on threatened marine fauna. Bycatch of small cetaceans by the Peruvian small-scale driftnet fleet results in the deaths of thousands of animals annually. We sought to assess the effectiveness of acoustic alarms (pingers) for reducing the incidental capture of dolphins and porpoises by this fleet. Forty-three experimental trips (156 fishing sets) and 47 control trips (195 fishing sets) out of Salaverry Port, northern Peru, were observed from April 2009 to August 2011. Twenty-two percent of control sets captured small cetaceans (67 individuals) and 16% of experimental sets had captures of small cetaceans (33 individuals). The bycatch rate of experimental sets was 0.50 individuals km−2h−1, whereas for control sets the rate was 0.80 individuals km−2h−1. This 37% reduction in bycatch rate suggests that pingers may be effective in reducing the bycatch of small cetaceans in this fishery. Catch rates of the fishery's target shark and ray species were unchanged. Given the vast size of this fishery and its current levels of bycatch of small cetaceans (> 10,000 individuals annually), even the modest declines in bycatch we observed could result in reductions in mortality of hundreds or thousands of small cetaceans per annum. Challenges, including increased costs, to large-scale utilization of pingers have yet to be overcome. The harpooning of dolphins for use as bait will also need to be addressed for further reductions in dolphin and porpoise bycatch and mortality to be achievable.

scholarly journals Net Fisheries’ Métiers in the Eastern Mediterranean: Insights for Small-Scale Fishery Management on Kalymnos Island

Water ◽  
2019 ◽  
Vol 11 (7) ◽  
pp. 1509 ◽  
Author(s):  
Kyriakoula Roditi ◽  
Dimitris Vafidis
Keyword(s):  
Mediterranean Sea ◽  
Fishery Management ◽  
Eastern Mediterranean ◽  
Market Price ◽  
Aegean Sea ◽  
Small Scale ◽  
Target Species ◽  
Essential Information ◽  
Small Scale Fisheries ◽  
The Difference

Small-scale fisheries constitute an important component of coastal human societies. The present study describes the small-scale net fisheries on Kalymnos Island (south-east Aegean Sea) that harbors the largest small-scale fleet in the eastern Mediterranean Sea. In addition, this study aims to evaluate their characteristics and economics. Relevant métiers were identified through a multivariate analysis by inputting the main resources and fishing gear data that were recorded during landings. Four main practices were observed being used as fishing gears, gillnets and trammel nets, targeting the species Mullus barbatus, Boops boops, Mullus surmuletus, Scorpaena porcus, and Sepia officinalis. Further analysis, which incorporated data concerning the type of the gear used, revealed 11 distinct métiers. Most of these métiers are practiced by other Mediterranean small-scale fisheries as well, in terms of target species, gear and seasonality. However, the métier that had its target species as B.boops is not practiced in other Mediterranean small-scale fisheries. The seasonal rotation of métiers was determined by the availability of different species rather than their market price. The results revealed the difference in fishing practice used by the fishermen in the study area compared to other fishing practices in the Mediterranean Sea. In particular, the fishermen of this study area targeted more species (B.boops) with a very low market price. They also provided essential information for the development and implementation of management plans aiming at the sustainability of small-scale fisheries.

scholarly journals Understanding Social-Ecological Challenges of a Small-Scale Hilsa (Tenualosa ilisha) Fishery in Bangladesh

2019 ◽  
Vol 16 (23) ◽  
pp. 4814 ◽  
Author(s):  
Mozumder ◽  
Pyhälä ◽  
Wahab ◽  
Sarkki ◽  
Schneider ◽  
...  
Keyword(s):  
Fishery Management ◽  
Large Population ◽  
Primary Data ◽  
Small Scale ◽  
Management Approach ◽  
Social Resilience ◽  
Migration Routes ◽  
Small Scale Fisheries ◽  
Social Ecological ◽  
Tenualosa Ilisha

Small-scale fisheries (SSFs) have been playing a crucial role in meeting the basic needs of millions of people around the world. Despite this, the sustainability of global fisheries is a growing concern, and the factors enabling or constraining the sustainable management of small-scale fisheries remain poorly understood. Hilsa shad (Tenualosa ilisha) is the single most valuable species harvested in Bangladesh waters, serves nutrition, income, and employment to the large population. This study analyzed the state and challenges of hilsa fishery in the Gangetic River systems (Padma and Meghna Rivers) by using two frameworks, namely the social-ecological systems (SES) and drivers-pressure-state-impact-responses (DPSIR) frameworks. Primary data for this analysis were collected by in-depth interviews (n = 130) and focus group discussions (n = 8) with various stakeholders in the hilsa fisheries. The perspectives explored here have been both critical and constructive, including the identification of problems and suggestions for improving the management of this particular social-ecological system. Hilsa fisheries, however, have come under severe threat since 2003 because of population growth, overfishing, pollution, climate change, the disruption of migration routes due to siltation, etc. All these have caused reduced catches and less stable incomes for fishers. This, in turn, has led to poverty, malnutrition, social tensions, stakeholder conflicts, and debt cycles amongst more impoverished fishing communities. These problems have been compounded by improved fishing technology amongst larger-scale ventures, the use of illegal fishing gears, and the non-compliance of government fishery management programs. Recommendations include the promotion of community-supported fisheries, the enhancement of stakeholder’s social resilience, the introduction of co-management approach, an increase in incentives and formal financial supports, and possible community-managed sustainable ecotourism including hilsa fishing-based tourism.

scholarly journals First records of the megamouth shark Megachasma pelagios (Taylor, Compagno & Struhsaker, 1983) as bycatch in Peruvian small-scale net fisheries

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Nicolas Acuña-Perales ◽  
Francisco Córdova-Zavaleta ◽  
Joanna Alfaro-Shigueto ◽  
Jeffrey C. Mangel
Keyword(s):  
Small Scale ◽  
Species Occurrence ◽  
Small Scale Fisheries ◽  
Monitoring Programs ◽  
Fisheries Bycatch ◽  
Northern Peru ◽  
Megamouth Shark ◽  
Fishery Interactions ◽  
Scale Surface

AbstractBetween October 2018 and October 2019, seven megamouth sharks were reported as bycatch in the small-scale surface and midwater gillnet fisheries operating from the ports of Mancora and Salaverry in northern Peru. Here we present details of these specimens and bycatch events that represent the first documented records of this species in Peruvian waters, confirming their occurrence as fisheries bycatch. We recommend continued monitoring programs in small-scale fisheries toward assessing the extent of this species’ occurrence in Peru and its vulnerability to fishery interactions.

scholarly journals Impacts of small-scale fisheries on mangrove fish assemblages

2018 ◽  
Vol 76 (1) ◽  
pp. 153-164 ◽  
Author(s):  
José Amorim Reis-Filho ◽  
Euan S Harvey ◽  
Tommaso Giarrizzo
Keyword(s):  
Species Richness ◽  
Fishery Management ◽  
Management Practices ◽  
Fish Assemblages ◽  
Small Scale ◽  
Fishing Pressure ◽  
Community Size ◽  
Small Scale Fisheries ◽  
Fishing Impacts ◽  
The Impact

Abstract The data requirements and resources needed to develop effective indicators of fishing impacts on target stocks may often be great, especially for mangrove fisheries where, for example, tidal cycles sequentially flood and drain the habitat as a result of natural processes. Here, we used underwater video systems to evaluate the impact of small-scale fisheries on mangrove fish assemblages at four levels of fishing pressure (low, medium, high, and no pressure). The lowest values of species richness and abundance were recorded in the areas fished most intensively. Conversely, the highest species richness and the occurrence of larger-bodied fish were recorded in areas of reduced fishing activity, which was surprisingly similar to the “no fishing” areas. The slopes of the community size spectra steepened in response to exploitation, while the relative abundance of medium-sized fish (16–25 cm) declined. Fishing for local or regional markets, rather than subsistence, also led to a decrease in the abundance of larger fish (>41 cm). The marked response of population parameters to fishing pressure reflected the impact of unregulated small-scale fisheries on areas of mangroves. Fishery management practices that ignore contemporary changes in these environments are likely to overestimate long-term yields, leading to overfishing. Thus, size-based approaches to evaluating fishing pressure were suitable for detecting negative responses from the mangrove fish assemblages. A next step will be to integrate size- and species-based ecological approaches that provide mechanisms to address pronounced decreases in specific species as a more profitable indicator of fishing impacts on mangrove fish assemblages. This approach will allow the development of effective conservation and management strategies.

scholarly journals Length at maturity of two pelagic sharks (Isurus paucus and Carcharhinus longimanus) found off northern Cuba

2020 ◽  
Author(s):  
A Ruiz-Abierno ◽  
JF Márquez-Farías ◽  
M Trápaga-Roig ◽  
RE Hueter
Keyword(s):  
Stock Assessment ◽  
Logistic Models ◽  
Binary Logistic Regression ◽  
Small Scale ◽  
Shark Species ◽  
Longline Fishery ◽  
Regional Structure ◽  
Life History Data ◽  
Median Size ◽  
Management Measures

Many shark species show regional structure and seasonal movements, complicating the gathering of life history data needed for fisheries management. Length-at-maturity is a relatively straightforward trait to quantify through the sampling of fisheries landings and is of great value for stock assessment. We report here on the median size at maturity for the longfin mako (Isurus paucus) and the oceanic whitetip shark (Carcharhinus longimanus), two important pelagic sharks caught by the small-scale longline fishery operating off northwest Cuba. We determined the maturity stages for 118 longfin makos and 84 oceanic whitetip sharks, based on the development of internal and external organs. A binary logistic regression was applied to estimate model coefficients necessary to describe proportion mature at size and determine L50 and the steepness of the model (Φ). For the longfin mako, the parameters of logistic models for males were L50 = 215 cm TL (CI: 210–220 cm TL), Φ = 4.46 (CI: 2.30–8.64) and for females L50 = 230 cm TL (CI: 220–239 cm TL), Φ = 9.79 (CI: 5.15–18.62). For the oceanic whitetip shark, the parameters for males were L50 = 203 cm TL (CI: 186–220 cm TL), Φ = 14.59 (CI: 6.74–31.58) and for females L50 = 199 cm TL (CI: 187–211 cm TL), Φ = 7.48 (CI: 2.56–21.8). The parameters presented here contribute to stock assessment and management measures for global conservation of these transboundary, highly vulnerable species of pelagic sharks.

Improving stock assessment and management advice for data-poor small-scale fisheries through participatory monitoring

2017 ◽  
Vol 190 ◽  
pp. 71-83 ◽  
Author(s):  
John Gabriel Ramírez ◽  
Jordi Lleonart ◽  
Marta Coll ◽  
Francisco Reyes ◽  
Gina Marcela Puentes
Keyword(s):  
Stock Assessment ◽  
Small Scale ◽  
Participatory Monitoring ◽  
Small Scale Fisheries ◽  
Management Advice

Comparing performance of catch-based and length-based stock assessment methods in data-limited fisheries

2020 ◽  
Vol 77 (6) ◽  
pp. 1026-1037 ◽  
Author(s):  
Maite Pons ◽  
Jason M. Cope ◽  
Laurence T. Kell
Keyword(s):  
Closed Loop ◽  
Stock Assessment ◽  
Maximum Sustainable Yield ◽  
Assessment Methods ◽  
Small Scale ◽  
Small Scale Fisheries ◽  
Management Procedures ◽  
Spawning Potential Ratio ◽  
The Common ◽  
The One

The quantity of data from many small-scale fisheries is insufficient to allow for the application of conventional assessment methods. Even though in many countries they are moving to closed-loop simulations to assess the performance of different management procedures in data-limited situations, managers in most developing countries are still demanding information on stock status. In this study we use the common metric of harvest rate to evaluate and compare the performance of the following catch-only and length-only assessment models: catch – maximum sustainable yield (Catch-MSY), depletion-based stock reduction analysis (DBSRA), simple Stock Synthesis (SSS), an extension of Catch-MSY (CMSY), length-based spawning potential ratio (LBSPR), length-based integrated mixed effects (LIME), and length-based Bayesian (LBB). In general, results were more biased for slightly depleted than for highly depleted stocks and for long-lived than for short-lived species. Length-based models, such as LIME, performed as well as catch-based methods in many scenarios, and among the catch-based models, the one with the best performance was SSS followed by CMSY.

Sign in / Sign up

Export Citation Format

Share Document