scholarly journals Multi-Indicator Harvest Strategies for Data-Limited Fisheries: A Practitioner Guide to Learning and Design

2021 ◽  
Vol 8 ◽  
Author(s):  
William J. Harford ◽  
Ricardo Amoroso ◽  
Richard J. Bell ◽  
Matias Caillaux ◽  
Jason Marc Cope ◽  
...  

As the world population grows, fisheries practitioners will be under increased pressure to address global challenges in data-limited fisheries management. With a focus on addressing localized and case-specific management needs, we provide a practical guide to the design and development of multi-indicator frameworks for fishery management. In a data-limited context, indicators are observations or estimates of the state of the fishery resource that are typically proxies for variables of interest, rather than quantities such as stock biomass estimated from data-rich stock assessments. Indicator frameworks structure the integration and interpretation of indicators to guide tactical fishery decision-making, often when the application of more formal analytical assessments is not feasible, yet where indicators in combination provide insight into stock status. With a focus on multi-indicator frameworks, we describe a pragmatic approach for their development via a set of organizational steps, considering a wide spectrum of types and severity of information limitations. We highlight where multi-indicator frameworks can be insightful and informative in relation to single indicator approaches but also point to potential pitfalls, with emphasis on critical evaluation and detection of performance flaws during the design phase using methods such as management strategy evaluation.

2018 ◽  
Vol 75 (8) ◽  
pp. 1215-1229 ◽  
Author(s):  
Lauren C. Scopel ◽  
Antony W. Diamond ◽  
Stephen W. Kress ◽  
Adrian R. Hards ◽  
Paula Shannon

Ecosystem-based fishery management requires understanding of relationships between exploited fish and their predators, such as seabirds. We used exploratory regression analyses to model relationships between Atlantic herring (Clupea harengus) in the diet of seabird chicks at nine nesting colonies in the Gulf of Maine and four types of fishery- and survey-derived herring data. We found several strong relationships, which suggests spatial structuring in herring stocks and likely patterns of herring movements before they recruit into the fishery. Some types of herring data seldom used in stock assessments — notably acoustic surveys, fixed-gear landings, and mass-at-age (i.e., weight-at-age) — correlated as strongly with seabird data as more commonly used series, such as mobile-gear landings and modeled spawning stock biomass. Seabird chick diets collected at specific locations thus offer a promising means to assess the size, distribution, and abundance of juvenile herring across a broad area prior to recruitment, which is a major source of uncertainty in fisheries. Common terns (Sterna hirundo) showed the most potential as a bioindicator, correlating well and showing consistent spatial patterns with 11 of 13 fishery data series.


Author(s):  
John R Wiedenmann ◽  
Daniel S Holland

Abstract Fisheries managed with explicit annual catch limits often have realized catches below the total allowable catch. Carry-over provisions allowing aggregate or individual carry-forward of catch underages are included in many fishery management systems, but the ramifications of these provisions on different fishery management objectives such as average catch, variability in catch, and probability and degree of overfishing are not well understood. We developed a management strategy evaluation simulation to explore performance of alternative carry-over policies assuming different life histories and under different causes of catch underages. We evaluated the impacts of the carry-overs across common management objectives to understand the trade-offs associated with different amounts of allowable carry-over. We find that carry-overs can increase yield to the fishery but can also increase the risks of overfishing, low stock biomass, low catch, and the interannual variability in catch. All of these risk measures increase with the amount of carry-over allowed in most cases, but for cases of low stock productivity or positively biased stock assessment estimates, larger carry-over allowances resulted in similar or lower yield compared to smaller allowances. The analysis suggests that some benefits of carry-over can be maintained and risks can be limited by restricting the maximum carry-over allowed.


Author(s):  
Ali Forouzanfar ◽  
Hamideh Sadat Mohammadipour ◽  
Fatemeh Forouzanfar

: Periodontal diseases are highly prevalent and can affect high percentage of the world population. Oxidative stress and inflammation plays an important role in the pathogenesis of periodontal diseases. Nowadays, more attention has been focused on the herbal remedies in the field of drug discovery. Green tea is an important source of polyphenol antioxidants, it has long been used as a beverage worldwide. The most interesting polyphenol components of green tea leaves that are related with health benefits are the catechins. Taken together this review suggested that green tea with its wide spectrum of activities could be a healthy alternative for controlling the damaging reactions seen in periodontal diseases.


2021 ◽  
Vol 7 (3) ◽  
Author(s):  
M. Lavanya

AbstractCorrosion results from the electrochemical reactions between the metal and its existing environment. Corrosion results in severe and expensive damage to a wide spectrum of industries. When microbes are involved in corrosion it is seldom possible to economically evaluate its impact. Microbially influenced corrosion is recognized to cause catastrophic failures contributing to approximately 20% of the annual losses. In many engineering applications, microbially influenced corrosion control is of prime importance. Expensive, toxicity and sometimes, even ineffectiveness of the current chemical strategies to mitigate microbially influenced corrosion have shifted the interest towards eco-friendly inhibitors. The present review discusses microbial induced corrosion in various metals and its inhibition through eco-friendly inhibitors. In addition, the study also reviews the morphological and electrochemical impedance results.


Materials ◽  
2018 ◽  
Vol 11 (12) ◽  
pp. 2557 ◽  
Author(s):  
Seo Lee ◽  
Jae Kang ◽  
Dokyoung Kim

Porous silicon has been utilized within a wide spectrum of industries, as well as being used in basic research for engineering and biomedical fields. Recently, surface modification methods have been constantly coming under the spotlight, mostly in regard to maximizing its purpose of use. Within this review, we will introduce porous silicon, the experimentation preparatory methods, the properties of the surface of porous silicon, and both more conventional as well as newly developed surface modification methods that have assisted in attempting to overcome the many drawbacks we see in the existing methods. The main aim of this review is to highlight and give useful insight into improving the properties of porous silicon, and create a focused description of the surface modification methods.


2017 ◽  
Vol 15 (19) ◽  
Author(s):  
Marek Volt

Artiklis käsitlen Lev Tolstoi kunstiteooria retseptsiooni anglo-ameerika esteetikas. Esiteks formuleerin Tolstoi kunstidefinitsiooni ja selle põhimõistete kanoonilise tõlgenduse. Seejärel analüüsin määratlust ekstensionaalse adekvaatsuse alusel, keskendudes nii tavapäraste kui võimalike uute etteheidete paikapidavuse uurimisele. Kolmandaks püstitan küsimuse, kas Tolstoi kunstidefinitsiooni kriitika ekstensionaalse adekvaatsuse alusel on üldse õigustatud. Väidan, et kuigi senistel Tolstoi meta-esteetilise rehabiliteerimise katsetel esineb puuduseid, paljastab Tolstoi kunstiteooria immanentne kriitika – teooria vaagimine eeldustelt, millelt see kritiseerib oponeerivaid teooriaid –, et ekstensionaalsest adekvaatsusest lähtuv kriitika on õigustatud. My article discusses Tolstoy’s theory of art in the context of Anglo-American aesthetics. Although Tolstoy’s What is Art touches upon a very wide spectrum of subjects (the place of art in the world, justification of sacrifices made for completing art works, criticism of previous theories of aesthetics, especially of the theory of beauty, defining of art as the expression of feelings, judging of art as such based on the religious knowledge of the era, action mechanisms of beauty/pleasure-centred art, consequences, conditions of the value of art, the relations between art and science, etc.), it has mainly been examined from the aspects of judging and defining of art.The article focuses on Tolstoy’s definition of art and consists of three notional parts. First, I present the canonical formulation of Tolstoy’s definition of art – something is a work of art if and only if the person, who lives through the feeling(s), causes by external signs that the recipients live through the same feelings. I also present the canonical interpretation of its main concepts – the conditions for creation, transmitting and reception.Second, I have an analytical insight into the criticism of the canonical treatment, displaying and commenting on, but also responding and complementing the presented arguments. The extensional adequacy-based analysis of Tolstoy’s definition of art shows that although it is possible to eliminate some of the typical criticisms, none of the three necessary conditions was necessary by itself, nor were all three of them sufficient when taken together.As Tolstoy’s definition of art has sometimes earned quite serious criticism, then, as my third point, I also examine some possibilities for rehabilitating Tolstoy’s theory of art: whether and in what sense can the extensional adequacy-based analysis of Tolstoy’s definition of art be justified at all? So far, the attempts of meta-aesthetic rehabilitation of Tolstoy (e.g., Mounce centrism) have not achieved the expected result. Furthermore, the immanent criticism of Tolstoy’s theory of art (criticism of the theory, based on the prerequisites it uses to criticize its opposing theories) reveals that the extensional adequacy-based criticism of Tolstoy’s definition of art is justified, but it is not necessarily the only yardstick for the theory.


2009 ◽  
Vol 1 (2) ◽  
pp. 291-297 ◽  
Author(s):  
K.K. Gupta ◽  
G. Prasad ◽  
A.K. Chopra ◽  
D.R. Khanna

Herbal drugs have been used as remedies for the treatment of large number of humans, ailments since ancient times as the traditional medicine system; India has a glorious past, having first documented record of fully developed medical science known as Ayurveda written by several ancient Rishi’s. Major groups of indigenous system of medicine are based on herbal drugs. A survey made by WHO indicated that about 80% of the world population relies on herbal drugs. Herbal drugs are becoming more popularized and important even in the developednations with hope of their non-toxicity and may play a role of substitute to overcome the problems of multi drug resistant pathogens. Cultivation of drug plants has been started in large scale without considering the land quality and in certain cases irrigation with waste water. Application of different fungicides, pesticides in that specific field or in neighboring fields may be directly deposited superficially or may be absorbed by the plant system. Therefore in the present situation possibilities of the Asian herbal drugs, contaminated with large number of toxic components cannot be ignored which may severely hurt human life in place of healing or curing.These contaminants may be either alone or in combination and may be originated intrinsically, extrinsically and deliberately. Certain contaminants may be highly toxic and may cause severe adverse effect in the human system. Some of the important contaminants are the heavy metals like lead, arsenic, cadmium, mercury, copper and pesticides. Adulteration of modern drugs to enhance drug potency and heterogenous microbial population including human pathogens may contaminate both raw and powdered herbal drugs. Among these contaminants, microbial contamination seems more severe and may be due to their dual action on the drug i.e. utilization of medicinally important chemical components as nutrients and in certain cases by producing certain mycotoxins, which may be even carcinogenic under certain conditions . Critical evaluation of both raw and powdered herbal drugs for contaminants is the urgent need of the time in order to provide safety measures in herbal health care medicine.


2019 ◽  
Vol 6 (3) ◽  
pp. 181700 ◽  
Author(s):  
Katrin Pretterebner ◽  
Luis Miguel Pardo ◽  
Kurt Paschke

Male-biased fishery management can provoke depletion of seminal reserves, which is the primary cause of sperm limitation. Therefore, identifying factors which contribute to the vulnerability to depletion of seminal reserves is a priority. The present study aimed to determine the effect of temperature on the recovery rate of sperm and seminal reserves after their depletion in Lithodes santolla , an important fishery resource in southern Chile. Sperm and seminal reserves were not fully recovered within 30 days. Temperature significantly affected seminal recovery: after 30 days the recovery index increased to 40% and 21% at 9°C and 12°C, respectively. The twice as fast seminal recovery at 9°C may be explained by the zone of origin of the individuals in this study (northern distributional limit), and 12°C may be close to the threshold of temperature tolerance. Lithodes santolla populations subject to intense male-only fisheries may be vulnerable to depletion of seminal reserves and a climate change scenario could additionally aggravate the risk of seminal depletion in L. santolla in its northern distributional limit.


2007 ◽  
Vol 64 (6) ◽  
pp. 1077-1084 ◽  
Author(s):  
Jon T. Schnute ◽  
Mark N. Maunder ◽  
James N. Ianelli

Abstract Schnute, J. T., Maunder, M. N., and Ianelli, J. N. 2007. Designing tools to evaluate fishery management strategies: can the scientific community deliver? – ICES Journal of Marine Science, 64: 1077–1084. Techniques for quantitative fishery management have evolved rapidly during a period when computers, programming languages, and computational algorithms have also changed dramatically. Despite these advances, many stock assessment methods remain untested. A process of management strategy evaluation (MSE) could potentially rectify this problem, but it would require a framework in which to conduct systematic tests. We survey the tools currently used for stock assessments and discuss the development of new standards for testing management procedures. A successful project would depend on human skills scattered among various nations, organizations, and academic disciplines. Analogies from civil engineering illustrate the discipline and collaboration required for an effective outcome. If the world community of fishery scientists could design, build, and support such a project, it would revolutionize the theory, teaching, and practice of scientific fishery management.


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