scholarly journals Evaluation of the current state of small pelagic fisheries in the Colombian Pacific: ensuring the sustainability of the resource and evaluating its response to climatic events

2013 ◽  
Vol 33 ◽  
pp. 63-68 ◽  
Author(s):  
L. A. Zapata ◽  
B. S. Beltrán-León ◽  
J. C. Herrera ◽  
P. Jiménez-Tello ◽  
L. M. Prieto ◽  
...  
Keyword(s):  
Marine Mammals ◽  
Commercial Fishing ◽  
Spawning Period ◽  
Thermal Anomalies ◽  
Current State ◽  
Management Measures ◽  
Canned Foods ◽  
Total Capture ◽  
Reproductive Processes ◽  
Eggs And Larvae

Abstract. Commercial fishing of small pelagic species in Colombia, mainly "carduma" (Cetengraulis mysticetus) and "plumuda" (Opisthonema spp.), has been recorded since 1970. Both are used to produce fish meal for aquaculture and poultry and for canned foods. These two species are filter feeders, and therefore support higher levels of the food chain (other fish, birds and marine mammals), and artisanal fishermen use them as bait. Between 2005 and 2010, 86.131 t have been captured (X = 14.355 t yr−1), and a strong reduction was noticed in 2009 (6.969 t). Carduma is considered a total spawning species. However, from 1997 to 2000 and from 2008 to date, atypical reproductive behavior of the species has been observed, including partition of the spawning period and the reduction of the volume of eggs and larvae released to the environment. Both situations are linked to thermal anomalies such as El Niño and La Niña events. Therefore, the process of assigning the global quota of extraction has been revised to take into account the reduction of total capture during the last years and the inconsistencies of the reproductive processes. The Ministry of Agriculture reduced the quota by 10%, leaving available a total of 27 000 t for 2010 and reduced it again to 25 000 t for 2011. It is important to maintain the management measures that are already implemented on this resource (bans during reproduction seasons, catch quotas, regulation of mesh sizes for the fishing nets, and limiting the number of new vessels) and considering other measures such as season closure for recruitment and establishment of marine protected areas to further contribute to the sustainability of these fisheries.

scholarly journals Sex- and size-selective harvesting of corkwing wrasse (Symphodus melops)—a cleaner fish used in salmonid aquaculture

2016 ◽  
Vol 74 (3) ◽  
pp. 660-669 ◽  
Author(s):  
Kim Tallaksen Halvorsen ◽  
Tonje Knutsen Sørdalen ◽  
Leif Asbjørn Vøllestad ◽  
Anne Berit Skiftesvik ◽  
Sigurd Heiberg Espeland ◽  
...  
Keyword(s):  
Commercial Fishing ◽  
Fishing Mortality ◽  
Size Selectivity ◽  
Negative Effects ◽  
Capture Process ◽  
Spawning Period ◽  
Open Site ◽  
Management Measures ◽  
Slot Size ◽  
Size Limits

Fishery-induced changes in sex ratios can have negative effects on reproductive rates and affect sexual selection and evolutionary trajectories. Here, we investigate sex- and size-selectivity of the fishery for corkwing wrasse (Symphodus melops) in Western Norway. The males that build and guard nests (nesting males) grow faster than females and sneaker males. Corkwing wrasse were tagged (n = 1057) during (May–June) and after (July) the spawning period in 2014 within a no-take site and in a nearby site open for fishing. We monitored the fishery within and nearby the tagging sites from June to October and sampled recaptures on all commercial fishing trips. Fishing mortality was higher for nesting males than for females (open site; tagged during spawning: 36% vs. 29%; after spawning: 49% vs. 36%) and was found to be caused by nesting males having higher capture probabilities than females, independently of body size. The fishing mortality of sneaker males did not differ from nesting males, but the sample of sneaker males in the study was small. The probability of being retained by fishers once captured depended on size, but not on sex. The small no-take site reduced fishing mortality, and the sex- and size-selectivity was similar to the open site. By demonstrating the capture process to be male-selective in a commercial fishery, our study highlights the importance of assessing sex-selectivity in similar fisheries. If detected, management measures protecting the sexes more equally should be implemented, such as slot-size limits and marine-protected areas large enough to account for sexual differences in spatial behaviour.

scholarly journals Effect of a fish stock's demographic structure on offspring survival and sensitivity to climate

2017 ◽  
Vol 114 (6) ◽  
pp. 1347-1352 ◽  
Author(s):  
Leif Christian Stige ◽  
Natalia A. Yaragina ◽  
Øystein Langangen ◽  
Bjarte Bogstad ◽  
Nils Chr. Stenseth ◽  
...  
Keyword(s):  
Gadus Morhua ◽  
Barents Sea ◽  
Condition Index ◽  
Wide Distribution ◽  
Commercial Fishing ◽  
Demographic Structure ◽  
Data Set ◽  
Spawning Period ◽  
Spawning Stock ◽  
Eggs And Larvae

Commercial fishing generally removes large and old individuals from fish stocks, reducing mean age and age diversity among spawners. It is feared that these demographic changes lead to lower and more variable recruitment to the stocks. A key proposed pathway is that juvenation and reduced size distribution causes reduced ranges in spawning period, spawning location, and egg buoyancy; this is proposed to lead to reduced spatial distribution of fish eggs and larvae, more homogeneous ambient environmental conditions within each year-class, and reduced buffering against negative environmental influences. However, few, if any, studies have confirmed a causal link from spawning stock demographic structure through egg and larval distribution to year class strength at recruitment. We here show that high mean age and size in the spawning stock of Barents Sea cod (Gadus morhua) is positively associated with high abundance and wide spatiotemporal distribution of cod eggs. We find, however, no support for the hypothesis that a wide egg distribution leads to higher recruitment or a weaker recruitment–temperature correlation. These results are based on statistical analyses of a spatially resolved data set on cod eggs covering a period (1959−1993) with large changes in biomass and demographic structure of spawners. The analyses also account for significant effects of spawning stock biomass and a liver condition index on egg abundance and distribution. Our results suggest that the buffering effect of a geographically wide distribution of eggs and larvae on fish recruitment may be insignificant compared with other impacts.

CURRENT STATE AND DEVELOPMENT PERSPECTIVES OF THE CASPIAN SPRAT FISHERIES

2018 ◽  
pp. 69-75
Author(s):  
Tatiana Vasilievna Pomogaeva ◽  
Aliya Ahmetovna Aseinova ◽  
Yuriy Aleksandrovich Paritskiy ◽  
Vjacheslav Petrovich Razinkov
Keyword(s):  
Food Item ◽  
Growth Potential ◽  
North West ◽  
Marine Fishery ◽  
The North ◽  
Current State ◽  
West Part ◽  
Eggs And Larvae ◽  
Intensive Growth

The article presents annual statistical data of the Caspian Research Institute of Fishery. There has been kept track of the long term dynamics of the stocks of three species of Caspian sprat (anchovy, big-eyed kilka, sprat) and investigated a process of substituting a food item of sprats Eurytemora grimmi to a small-celled copepod species Acartia tonsa Dana. According to the research results, there has been determined growth potential of stocks of each species. Ctenophoran-Mnemiopsis has an adverse effect on sprat population by eating fish eggs and larvae. Ctenophoram - Mnemiopsis is a nutritional competitor to the full-grown fishes. The article gives recommendations on reclamation of stocks of the most perspective species - common sprat, whose biological characteristics helped not to suffer during Ctenophoram outburst and to increase its population during change of the main food item. Hydroacoustic survey data prove the intensive growth of common sprat biomass in the north-west part of the Middle Caspian. According to the results of the research it may be concluded that to realize the volumes of recommended sprat catch it is necessary to organize the marine fishery of common sprat at the Russian Middle Caspian shelf.

BASIC ASPECTS OF THE FISCAL POLICY OF THE STATE IN THE SUBJECT OF THE RUSSIAN FEDERATION

2020 ◽  
Vol 1 (6) ◽  
pp. 4-7
Author(s):  
B. Kh. ALIYEV ◽  
Keyword(s):  
Fiscal Policy ◽  
Russian Federation ◽  
Economic Management ◽  
Financial Flows ◽  
Constituent Entity ◽  
Current State ◽  
Management Measures ◽  
The Subject ◽  
The Russian Federation ◽  
The Republic

The article examines the current state of the fiscal policy of the constituent entity of the Russian Federation, which is a combination of diverse economic management measures based on the distribution and redistribution of financial flows. The analysis of fiscal policy on the example of the subject of the Russian Federation (Republic of Dagestan). The article outlines the problematic issues of the tax policy of the Republic of Dagestan and suggests ways to overcome the identified problems.

scholarly journals Natura 2000 sites and fisheries in German offshore waters

2008 ◽  
Vol 66 (1) ◽  
pp. 155-169 ◽  
Author(s):  
Søren Anker Pedersen ◽  
Heino Fock ◽  
Jochen Krause ◽  
Christian Pusch ◽  
Anne L. Sell ◽  
...  
Keyword(s):  
Marine Mammals ◽  
Fishery Management ◽  
Conservation Status ◽  
Natura 2000 ◽  
Management Measures ◽  
Favourable Conservation Status ◽  
Management Plans ◽  
Natura 2000 Site ◽  
Environmentally Sound ◽  
Fishing Impacts

Abstract Pedersen, S. A., Fock, H., Krause, J., Pusch, C., Sell, A. L., Böttcher, U., Rogers, S. I., Sköld, M., Skov, H., Podolska, M., Piet, G. J., and Rice, J. C. 2009. Natura 2000 sites and fisheries in German offshore waters.–ICES Journal of Marine Science, 66: 155–169. The principal objective of sites selected as part of Natura 2000 is to achieve or maintain a favourable conservation status of habitats and species named in the EU Birds and Habitats directives. In the German exclusive economic zone, the habitat types protected by this legislation are sandbanks and reefs; protected species include marine mammals, seabirds, and specific migratory fish species. The ICES project Environmentally Sound Fishery Management in Protected Areas (EMPAS) aims to answer two questions: (i) To what extent do specific fishing activities significantly threaten attainment of the conservation objectives of the Natura 2000 sites? (ii) What management measures would reduce these conflicts and how effective would they be at helping to ensure the favourable condition of these sites? Assessments of fishing impacts on Natura 2000 sites require basic data on the conservation status of individual habitats and species, as well as data for fine-scale distributions of ongoing fishing activities. This paper describes and discusses the process used by the EMPAS project in developing fishery-management plans for each Natura 2000 site in German offshore waters.

scholarly journals The Painful Side of Trap and Fixed Net Fisheries: Chronic Entanglement of Large Whales

2012 ◽  
Vol 2012 ◽  
pp. 1-4 ◽  
Author(s):  
Michael J. Moore ◽  
Julie M. van der Hoop
Keyword(s):  
Marine Mammals ◽  
Well Being ◽  
Eubalaena Glacialis ◽  
North Atlantic Right Whale ◽  
Right Whale ◽  
The North ◽  
Management Measures ◽  
Population Sustainability ◽  
The Individual ◽  
Severe Tissue

Concern over the well-being of marine mammals at sea has focused on intentional harvests, both in terms of individual welfare and population sustainability. Unintentional mortalities from fishing gear entanglement are primarily seen as a risk to population viability. Additionally, larger whales breaking free of, and subsequently carrying, fixed trap and net gear are subject to a very slow demise, averaging 6 months in the case of the North Atlantic right whale (Eubalaena glacialis). Chronic cases can involve impaired foraging, increased drag, infection, hemorrhage, and severe tissue damage. The individual suffering of these cases appears to be extreme. Thus management measures should go beyond legally mandated conservation measures to include avoidance of such scenarios. Seafood consumers could succeed, where laws have failed, to demand fishing practices that do not kill whales in this manner. The effective absence of such demands would seem to reflect the cryptic nature of these cases to most consumers.

scholarly journals Welfare of aquatic animals: where things are, where they are going, and what it means for research, aquaculture, recreational angling, and commercial fishing

2018 ◽  
Vol 76 (1) ◽  
pp. 82-92 ◽  
Author(s):  
Howard I Browman ◽  
Steven J Cooke ◽  
Ian G Cowx ◽  
Stuart W G Derbyshire ◽  
Alexander Kasumyan ◽  
...  
Keyword(s):  
Strong Support ◽  
Legal Protection ◽  
Regulatory Environment ◽  
Commercial Fishing ◽  
Aquatic Animal ◽  
Aquatic Animals ◽  
Scientific Debate ◽  
Current State ◽  
Recreational Angling ◽  
State Of Affairs

AbstractWe revisit the evidence attributing sentience-pain-suffering to aquatic animals. The objective is to inform readers of the current state of affairs, to direct attention to where research is needed, and to identify “wicked” questions that are difficult to resolve unequivocally. By separating the ethical from the scientific debate, applying organized skepticism to the latter, and taking a pragmatic approach that does not depend on resolving the “wicked” questions, we hope to focus and strengthen research on aquatic animal welfare. A second but closely-related objective is to briefly summarize the research used to support the regulations governing the welfare of aquatic animals, particularly its limitations. If you interact with aquatic animals, these regulations already affect you. If the regulatory environment continues on its current trajectory (adding more aquatic animal taxa to those already regulated), activity in some sectors could be severely restricted, even banned. There are surely some lively debates and tough choices ahead. In the end, extending legal protection to aquatic animals is a societal choice, but that choice should not be ascribed to strong support from a body of research that does not yet exist, and may never exist, and the consequences of making that decision must be carefully weighed.

scholarly journals From strategic ambiguity to technical reference points in the Antarctic krill fishery: the worst journey in the world?

2013 ◽  
Vol 40 (4) ◽  
pp. 394-405 ◽  
Author(s):  
SIMEON L. HILL
Keyword(s):  
Antarctic Krill ◽  
Drake Passage ◽  
Simulation Models ◽  
Reference Points ◽  
Multiple Predators ◽  
Scotia Sea ◽  
Current State ◽  
Management Measures ◽  
Spatial Subdivision ◽  
Ecosystem State

SUMMARYThe goals of ecosystem based management (EBM) are strategically ambiguous, meaning that they require interpretation to identify objectives for ecosystem state. Ecosystem states that are useful for achieving such objectives are known as reference points. Soft reference points specify both a state and a probability of the ecosystem being in that state. They are used with simulation models to identify management measures for which the risk of the ecosystem entering an undesirable state is below a specified level. The Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR) is responsible for the EBM of Antarctic krill fisheries. CCAMLR used soft reference points for the krill stock in the Scotia Sea and southern Drake Passage to set a regional catch limit. However, this catch limit needs spatial subdivision to protect predators from localized depletion. Model-based evaluations of different options for subdividing the catch limit used illustrative reference points to assess the depletion risk to multiple predators. This study demonstrates that the apparent risk is sensitive to the choice of reference point and method for aggregating modelled predators. EBM practitioners and stakeholders need to be aware that these factors could therefore bias comparisons of management measures. Nonetheless, qualitative distinctions between different spatial subdivision options are relatively consistent except at high levels of aggregation and extreme reference points. This study also demonstrates a lack of generality in the relationship between current and future ecosystem state. Thus, the EBM goal of maintaining ecosystem resilience implies different reference points for the current state of different ecosystem components. Despite early progress in defining soft reference points for the krill stock, CCAMLR has not yet defined reference points for krill predators. Structured dialogue aimed at identifying collective objectives might be necessary to achieve further progress in CCAMLR and other EBM organizations.

scholarly journals Aspects of the biology of the Atlantic Midshipman, Porichthys porosissimus (Teleostei, Batrachoididae): an important by-catch species of shrimp trawling off southern Brazil

2000 ◽  
Vol 48 (2) ◽  
pp. 131-140 ◽  
Author(s):  
Marcelo Vianna ◽  
Acácio R. G. Tomas ◽  
José R. Verani
Keyword(s):  
Growth Parameters ◽  
Northern Coast ◽  
Pink Shrimp ◽  
Stock Management ◽  
Spawning Period ◽  
Management Measures ◽  
Shrimp Trawl ◽  
Trawl Fishing ◽  
By Catch ◽  
The Impact

Trawl fishing for pink shrimp (Farfantepenaeus brasiliensis and F. paulensis) catches large quantities of by-catch fish, discarded due to their having no commercial va)ue. As these species have rarely been studied, the impact of fisheries on these populations is not known. This contribution studies the biology of a species of no commercial value, the Atlantic midshipman Porichthys porosissimus. The last haul /Tom a commercial trawler, operating on the northern coast of São Paulo State and the southern coast of Rio de Janeiro State, was preserved (/Tom being discarded) and identified at the species leveI. It was observed that this fishery affects the juvenile population which is intluenced by the seasonal variation of the water masses. Growth parameters were estimated: L∞ = 37.0 cm, K = 0.285 year-1. Instantaneous mortality coefficients were estimated: 2=2.14, M=0.63, F= 1.51, S= 11.8 and E=0.71. Considering the intensive activity of the shrimp trawl tleet operating in this area, the deleterious action of trawling is considered as of high impact. The stock management measures applied for pink shrimp are without effect regarding P. porosissimus. which has its spawning period before the closed season and its recruitment peak after it. The results show overfishing and the need to apply measures to reduce trawling action, such as adequate policies, introduction of selectivity devices and the creation of exclusion zones for trawl fishing.

scholarly journals Sustainability: A flawed concept for fisheries management?

Elem Sci Anth ◽  
2019 ◽  
Vol 7 ◽  
Author(s):  
Richard Stafford
Keyword(s):  
Carbon Capture ◽  
Marine Conservation ◽  
Commercial Fishing ◽  
Economic Modelling ◽  
Underlying Assumption ◽  
Security Issues ◽  
Economic Exploitation ◽  
Management Measures ◽  
Definition Of

The concept of sustainable fishing is well ingrained in marine conservation and marine governance. However, I argue that the concept is deeply flawed; ecologically, socially and economically. Sustainability is strongly related, both historically and currently, to maximum long-term economic exploitation of a system. Counter-intuitively, in fisheries, achieving this economic exploitation often relies on government subsidies. While many fish populations are not sustainably fished biologically, even ‘sustainably harvesting’ fish results in major ecological changes to marine systems. These changes create unknown damage to ecosystem processes, including carbon capture potential of the ocean. The spatial scale of commercial fishing processes can also lead to social and food security issues in local, coastal communities that rely on fish for dietary needs. A radical alternative proposal is provided to the current situation. Ultimately, offshore fishing should be stopped completely and fish catches should rely instead on inshore fisheries. While such an approach may require a change in thinking and human behaviour regarding fish, I demonstrate that there are many benefits of this approach, including ecological, social and to local coastal economies, and few negatives, although management measures and coastal marine protected areas to protect vulnerable species and habitats would still be required. As such, the approach suggested is much more akin to a holistic definition of sustainability or ‘prevention of ecological harm’, rather than the maximum long-term exploitation of an ecosystem which is an underlying assumption of much fisheries and conservation research. While the suggestions in the study would benefit from further ecological, social and economic modelling, any movement towards restricting offshore catches should provide some degree of the benefits detailed.

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