Perspectives on Fisheries Biology and Implications for Management

1979 ◽  
Vol 36 (7) ◽  
pp. 838-844 ◽  
Author(s):  
L. M. Dickie
Keyword(s):  
Species Composition ◽  
Key Words ◽  
Fisheries Management ◽  
Biological Efficiency ◽  
Biological Structure ◽  
Predator Prey ◽  
Natural Production ◽  
Technological Efficiency ◽  
Basic Characteristics ◽  
Fisheries Biology

Descriptions of fisheries systems for purposes of management often seem to imply a naturally predetermined biological structure and functioning of the resource. However, such basic characteristics as stock definition, species composition, levels of production, and biological efficiency are parameters that have generally been adapted to suit particular fishery conditions and in any case are variables that interact with both environment and the nature of industrial exploitation. In the interests of economic or social analyses in fisheries these biological descriptors should normally be amenable to redefinition or redescription without prejudice to their reliability as indices of natural production. Key words: fisheries management, economic objectives, unit stock concept, variability, fisherman's choice, predator–prey relations, biological and technological efficiency

scholarly journals Por uma racionalidade ambiental: reflexões acerca dos regramentos propostos para pesca da tainha no estuário da Lagoa dos Patos/RS

2018 ◽  
Vol 23 (1) ◽  
pp. 31-53
Author(s):  
Tatiana Walter ◽  
Liandra Peres Caldasso ◽  
Jéssica Fischer ◽  
Ivanilda Foster Almeida
Keyword(s):  
Key Words ◽  
Fisheries Management ◽  
Scientific Discourse ◽  
Artisanal Fisheries ◽  
Environmental Conflicts ◽  
Patos Lagoon ◽  
External Market ◽  
Artisanal Fishers ◽  
South Of Brazil ◽  
Fisheries Biology

As reflexões aqui expostas versam sobre a contribuição do Estado, apoiado no discurso científico, em regulações ambientais que têm como premissa uma visão dicotômica entre sociedade e ambiente. Ao não reconhecerem outras racionalidades na relação com o ambiente, as normativas nada mais são do que mecanismos promotores de conflitos ambientais. Nossa análise tem como suporte as normativas em vigor com vistas à gestão da tainha no sudeste e sul do Brasil, em especial, no estuário da Lagoa dos Patos/RS. Verificamos que as proposições se dão em uma perspectiva biologicista e estado-centrada que, ao mesmo tempo em que, inviabilizam a manutenção dos modos de vida dos pescadores(as) artesanais desta região, dão sustentação a uma pesca industrial destinada ao mercado externo. For an environmental rationality: reflections about the proposed rules for fishing for mullet in the estuary of Lagoa dos Patos / RS The reflections presented here discuss the contribution of the Statein environmental regulations, supported by the scientific discourse predominantly of fisheries biology, that have as premise a dichotomous vision between society and environment. By not recognizing other rationalities in relation to the environment, the regulations are nothing more than mechanisms that promote environmental conflicts. Our analysis is based on current regulations for the management of mullet fisheries in the southeast and south of Brazil, especially in the estuary of Patos Lagoon/RS. We have verified that the propositions take place in a biologicist and state-centered perspective that, at the same time, make it impossible to maintain the livelihoods of the artisanal fishers of this region, and give support to an industrial fishing destined to the external market. Key-words: artisanal fisheries, environmental conflicts, fisheries management, mullet, Patos Lagoon / RS.

scholarly journals Peculiarities of successional changes of xylotrophic basidiomycetes during decomposition of dominant tree species of forest formations of the Pitsunda-Myussera Reserve of the Republic of Abkhazia

2021 ◽  
Vol 35 ◽  
pp. 00014
Author(s):  
Sofia Khacheva
Keyword(s):  
Species Composition ◽  
Key Words ◽  
Tree Species ◽  
Xylotrophic Basidiomycetes ◽  
Xylotrophic Fungi ◽  
The Republic ◽  
Destructive Processes

The article is about the biodiversity of xylotrophic fungi of oak and hornbeam forests of Abkhazia and related destructive processes of the main forest-forming species (oak and hornbeam). The species composition of fungi subjected to phytopathogenic and saprotrophic methods of decomposition was determined. The species composition of mycobiota, causing wood xylolysis practically up to the last stages of decomposition, has been determined. Key words: biodiversity, xylotrophic fungi, succession, Republic of Abkhazia.

scholarly journals ANALISIS KOMUNITAS MANGROVE DI KECAMATAN SEKOTONG LOMBOK BARAT NTB

2019 ◽  
Vol 19 (1) ◽  
Author(s):  
Lalu Japa ◽  
Didik Santoso
Keyword(s):  
Cluster Analysis ◽  
Species Composition ◽  
Key Words ◽  
Tree Density ◽  
Mangrove Tree ◽  
Rhizophora Apiculata ◽  
Percentage Similarity ◽  
Percentage Covering ◽  
Very High ◽  
Program Version

Abstrak:Komunitas mangrove di kawasan Sekotong Lombok Barat telah diteliti untuk mengetahui komposisi spesies, kerapatan  individu setiap spesies,dan  persentase tutupannya. Total sebanyak 28 plot (kudrat) berukuran 10m x 10m dibuat pada 9 transek di lima stasiun. Foto tutupan kanopi mangrove dan parameter komposisi komunitas dianalisis menggunakan software ImageJ dan template spreadsheet. Data kerapatan pohon dan persentase tutupan mangrove dianalisis dengan ANOVA. Persentase kesamaan antara stasiun menggunakan Biodiversity Program Version 2 berdasarkan the Bray Curtis Cluster Analysis. Komunitas mangrove di Kecamatan Sekotong Lombok Barat teridenfikasi 8 spesies, meliputi 5 genus, dan 4 famili. Rhizophora apiculata tersebar disemua transek penelitian. Transek SKTM02B memiliki kerapatan pohon tertinggi sebesar 2800 pohon/ha. Tiga transek dengan persentase tutupan tertinggi berturut-turut SKTM04T, SKTM04, dan SKTM01A. Persentase kesamaan antar stasiun sangat tinggi mencapai 82,503 –  95,423%. Persentase kesamaan tertinggi (95,423%) terjadi antara stasium SKTM04 dan SKTM05. Kata kunci : mangrove, Sekotong, komposisi spesies, kerapatan, dan persentase tutupan Abstract: Community of mangrove in the area of Sekotong West Lombok has been researched to know the species composition,  individual density of each species, and percentage covering. Total number of 28 plots of 10 m x 10 m in size were set in 9 transects in 5 station. Photographs mangrove canopy covering and parameter of mangrove community composition were analyzed by using the software ImageJ and  template spreadsheet. ANOVA was applied for analyzing the data of mangrove  tree density and percentage covering. The Bray Curtis Cluster Analysis. using Biodiversity Program Version 2 was also used for analyzing the percentage similarity among station. The community of mangrove of Sekotong West Lombok consists of 8 species, 5 genera, dan 4 family. Rhizophora apiculata was recorded in all transects. The highest density (2800 trees/ha) of mangrove was recorde in ransect SKTM02B.. The three transects with the highest percentage covering were SKTM04T, SKTM04, dan SKTM01A, respectively. Percentages similarity among station were very high (82,503%  –  95,423%). SKTM04 and SKTM05 were the two station with  the highest percentage similarity (95,423%). Key words : mangrove, Sekotong, species composition, density, and percentage covering 

Technique for Tagging Small Fish with I131 for Evaluation of Predator–Prey Relationships

1978 ◽  
Vol 35 (1) ◽  
pp. 143-145 ◽  
Author(s):  
Gerard J. FitzGerald ◽  
Miles H. A. Keenleyside
Keyword(s):  
Content Analysis ◽  
Key Words ◽  
Stomach Content ◽  
Stomach Content Analysis ◽  
Small Fish ◽  
Short Term ◽  
Predator Prey ◽  
Cichlasoma Nigrofasciatum ◽  
Quantitative Studies ◽  
Convict Cichlids

Experiments to test the feasibility of using radioactive I131 as a technique for evaluation of conspecifïc predation on fry by adult convict cichlids (Cichlasoma nigrofasciatum) are described. The technique is useful for short-term quantitative studies of predator–prey interactions where it is not possible to observe and quantify predation directly or where stomach content analysis of adults is not feasible. Key words: radioactive tagging, predator–prey interactions, Cichlasoma nigrofasciatum

Early patterns of revegetation of artificial earthen mounds in a northern mixed prairie

1992 ◽  
Vol 70 (1) ◽  
pp. 145-150 ◽  
Author(s):  
Charles E. Umbanhowar Jr.
Keyword(s):  
Species Composition ◽  
Key Words ◽  
Species Abundance ◽  
Bare Soil ◽  
Compositional Variation ◽  
Stem Density ◽  
Mixed Prairie ◽  
Outer Perimeter ◽  
Species Abundance Data ◽  
Key Words Colonization

Patches of bare soil are thought to be important to the diversity and structure of North American grasslands. In 1987, 45 7.5-dm diameter artificial earthen mounds were built in low-, mid-, and high-prairie types to experimentally study the effects of mound location on patterns of mound revegetation. Stem densities and species abundance data were recorded every other week during the summers of 1987 and 1988. Few stems were recorded in 1987, and stem density more than quadrupled in 1988, but less than 1 % of all stems were seedlings. Grass stem densities were significantly higher on low-prairie mounds than mid- or high-prairie mounds and were concentrated in the outer perimeter of mounds. Forb stem densities did not vary significantly between prairie types or on-mound position. Mound species composition closely resembled surrounding vegetation, reflecting between and within prairie-type compositional variation. Key words: colonization, disturbance, earthen mounds, northern mixed prairie, patch, revegetation.

The Systematics of Salmonid Fishes of Recently Glaciated Lakes

1972 ◽  
Vol 29 (6) ◽  
pp. 639-671 ◽  
Author(s):  
Robert J. Behnke
Keyword(s):  
Genetic Diversity ◽  
Reproductive Isolation ◽  
Fisheries Management ◽  
Common Ancestor ◽  
Morphological Divergence ◽  
Salmonid Fishes ◽  
Sympatric Populations ◽  
Homing Behavior ◽  
Taxonomic Problem ◽  
Fisheries Biology

The systematics of the subfamilies Salmoninae and Coregoninae of recently glaciated regions are reviewed. Interrelation between systematics and fisheries biology are stressed, pointing out the abundance of intraspecific genetic diversity of some salmonid fishes manifested in ecological and behavioral specializations, but not necessarily by morphological divergence. Innate, reproductive homing behavior of salmonid fishes may allow closely related populations to exist in sympatry and maintain reproductive isolation. Examples are cited to support the contention that many sympatric "sibling species" have evolved from a common ancestor in postglacial times. Closely related, sympatric populations are a major taxonomic problem, but this phenomenon which allows a species to consist of genetically discrete units with reproductive isolation between the stocks is of great significance for fisheries management. Postglacial salmonid communities are typically fragile and highly susceptible to disruption or destruction by introductions, eutrophication, and exploitation. Every effort should be made to protect the genetic diversity of a species.

scholarly journals Měkkýší fauna rybníka Strašík u Libouně (střední Čechy, okres Benešov) a poznámky k fauně rybníků na Podblanicku [The Molluscan Fauna of Strašík Pond by Libouň Village (Central Bohemia, Benešov District) and Several Notes to Malacofauna of Ponds in Podblanicko Region]

2003 ◽  
Vol 2 ◽  
pp. 19-26
Author(s):  
Vladimír Vrabec
Keyword(s):  
Czech Republic ◽  
Species Composition ◽  
Lymnaea Stagnalis ◽  
Point Of View ◽  
Quantitative Composition ◽  
Frequency Of Occurrence ◽  
Bithynia Tentaculata ◽  
Radix Peregra ◽  
Molluscan Fauna ◽  
Basic Characteristics

In the pond Strašík by Libouň (Czech Republic, WGS 84: 49°37'50"N, 14°49'30"E) 14 species of water molluscs were documented by the research executed on 8 June 2001: Radix peregra, Lymnaea stagnalis, Anisus vortex, Bathyomphalus contortus, Gyraulus albus, Gyraulus crista, Hippeutis complanatus, Musculium lacustre, Pisidium casertanum, Pisidium milium, Pisidium nitidum, Pisidium obtusale, Pisidium personatum, Pisidium subtruncatum. The basic characteristics of the community were determined: quantitative composition and dominance. The index of the concentrated dominance modified according to Simpson (c = 0,33) was counted and compared with available data. The pond fauna was compared to the fauna of other examined ponds in Podblanicko. The total of 12 ponds were examined in this region or its closest surroundings so far and 21 species of water molluscs were found in them. The pond Strašík, analysed in this study, is richest in species variety, as it has 14 species, the least occupied are the ponds Splav by Bystřice (2 species) and the first pond above the pond Utopenec by Vlašim (3 species). In the case of these ponds the result is probably due to the fact that they are relatively little known. The species Anisus vortex, Lymnaea stagnalis and Gyraulus albus have the highest frequency of occurrence in the ponds examined so far in Podblanicko, the least frequent are the species Bithynia tentaculata, Acroloxus lacustris and Pisidium personatum. The similarity of the species composition of the ponds fauna was evaluated according to the Jaccard’s index. The pond most similar to the Strašík pond analyzed in this study is from the point of view of the species presence the pond Utopenec on the stream Orlina (8 and 12), which is situated nearby.

scholarly journals Anthropogenic transformation in the forests of upper-Dniester Beskidies and ways of its optimization

2009 ◽  
pp. 187-199
Author(s):  
P. Telish
Keyword(s):  
Species Composition ◽  
Key Words ◽  
Age Structure ◽  
Modern State ◽  
Anthropogenic Transformation

Some geographical features and modern state of forest fund of UpperDnister Beskidies are examined. The age-structure and class of bonitet are found out. The basic indexes of two basic users of forest fund are compared. The principles of optimization of cenotic structure of these forests are also grounded. Key words: forest fund, users of forest fund, secular frame, species composition, complexity of afforestation, class of bonitet.

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