scholarly journals Trawl fishing impacts on the status of seabed fauna in diverse regions of the globe

2020 ◽  
Vol 22 (1) ◽  
pp. 72-86
Author(s):  
Tessa Mazor ◽  
C. Roland Pitcher ◽  
Wayne Rochester ◽  
Michel J. Kaiser ◽  
Jan G. Hiddink ◽  
...  
Keyword(s):  
Trawl Fishing ◽  
The Status ◽  
Fishing Impacts

scholarly journals Comparing data-based indicators across upwelling and comparable systems for communicating ecosystem states and trends

2009 ◽  
Vol 67 (4) ◽  
pp. 807-832 ◽  
Author(s):  
Lynne J. Shannon ◽  
Marta Coll ◽  
Dawit Yemane ◽  
Didier Jouffre ◽  
Sergio Neira ◽  
...  
Keyword(s):  
Mediterranean Ecosystems ◽  
Complex Model ◽  
Environmental Forcing ◽  
Ecosystem Effects ◽  
The Status ◽  
Ecosystem Level ◽  
Trends Over Time ◽  
Fishing Impacts ◽  
Proper Interpretation ◽  
Ecosystem State

Abstract Shannon, L. J., Coll, M., Yemane, D., Jouffre, D., Neira, S., Bertrand, A., Diaz, E., and Shin, Y-J. 2010. Comparing data-based indicators across upwelling and comparable systems for communicating ecosystem states and trends. – ICES Journal of Marine Science, 67: 807–832. A suite of ecological indicators was selected for communicating, in a comparable way, how fishing affects the state of several upwelling ecosystems and others in which small pelagic fish play key ecological roles. Detailed background and understanding of system-specific processes and changes is needed for proper interpretation of results. In particular, environmental forcing is important in driving dynamics in upwelling systems; fishing impacts cannot be understood without understanding the corresponding dynamics of the environment. The Saharan Coastal (Morocco) and southern Benguela, both having experienced upsurges in low-trophic-level species, differed from other ecosystems when considering indicator trends. The ecosystem off Portugal emerged as showing reduced signs of fishing impacts in recent years, although the change may also be reflecting climate change favouring recruitment and abundance of demersal stocks. The indicator suite confirmed general understanding that the Mediterranean ecosystems have been notably degraded for several decades. Results and conclusions from this descriptive synthesis are compared with other comparisons of more complex, model-derived indicators. Even in upwelling and comparable systems, the simple data-based indicators are useful in synthesizing information on the status of an ecosystem, in particular on the ecosystem effects of fishing, to provide an ecological diagnosis at the ecosystem level, to be used in decision-making. Indicators of recent ecosystem state and trends over time are needed to assess the effects of fishing, but more indicators measuring biodiversity attributes and environmental change would complement the suite, providing fuller assessment of the status of upwelling and comparable ecosystems.

Distribution of population-based indicators across multiple taxa to assess the status of Gulf of Alaska and Bering Sea groundfish communities

2005 ◽  
Vol 62 (3) ◽  
pp. 344-352 ◽  
Author(s):  
Franz J. Mueter ◽  
Bernard A. Megrey
Keyword(s):  
Bering Sea ◽  
Gulf Of Alaska ◽  
Population Based ◽  
Fishing Effort ◽  
Frequency Of Occurrence ◽  
Catch Per Unit Effort ◽  
Eastern Bering Sea ◽  
Trawl Fishing ◽  
The Status ◽  
Commercial Species

Abstract Ecosystem-based approaches to fisheries management require researchers and managers to take into account effects of fishing on other components of the ecosystem, including non-commercial species. Currently, stock assessments in the Northeast Pacific are limited to the most important commercial species, little being known about the status of non-commercial species. Nevertheless, standardized bottom-trawl surveys conducted in the eastern Bering Sea (EBS) and Gulf of Alaska (GoA), although primarily designed to assess commercial species, provide valuable information on the abundance, distribution, and mean weight of numerous taxa. Using a novel statistical approach and survey data for the years 1993–2003, we examined trends in catch per unit effort (cpue), frequency of occurrence, and mean weight of individuals for each taxon. Time trends were computed as the slope of a linear regression of each indicator on year, and were summarized separately for the eastern and western GoA and for the EBS. Within each system, trends were further compared between commercial and non-commercial taxa. Simulations were used to obtain reference distributions for the expected distribution of slopes across many dependent populations. Observed distributions of trends were compared with simulated distributions, suggesting that more taxa than expected showed a decreasing trend in cpue in the EBS, but not in the GoA. These trends likely resulted from low groundfish productivity in the EBS during the 1990s. At the same time, the frequency of occurrence of significantly more taxa than expected increased in the EBS and, to a lesser extent, in the western GoA. Increases in frequency of occurrence were much more common among non-commercial, invertebrate taxa, and may be a response to reductions in trawl fishing effort during the 1990s.

scholarly journals Global assessment of the status of coral reef herbivorous fishes: evidence for fishing effects

2014 ◽  
Vol 281 (1774) ◽  
pp. 20131835 ◽  
Author(s):  
C. B. Edwards ◽  
A. M. Friedlander ◽  
A. G. Green ◽  
M. J. Hardt ◽  
E. Sala ◽  
...  
Keyword(s):  
Large Scale ◽  
Reef Fishes ◽  
Total Biomass ◽  
Herbivorous Fishes ◽  
Regulate Competition ◽  
The Status ◽  
Global Status ◽  
Algal Abundance ◽  
Herbivore Community ◽  
Fishing Impacts

On coral reefs, herbivorous fishes consume benthic primary producers and regulate competition between fleshy algae and reef-building corals. Many of these species are also important fishery targets, yet little is known about their global status. Using a large-scale synthesis of peer-reviewed and unpublished data, we examine variability in abundance and biomass of herbivorous reef fishes and explore evidence for fishing impacts globally and within regions. We show that biomass is more than twice as high in locations not accessible to fisheries relative to fisheries-accessible locations. Although there are large biogeographic differences in total biomass, the effects of fishing are consistent in nearly all regions. We also show that exposure to fishing alters the structure of the herbivore community by disproportionately reducing biomass of large-bodied functional groups (scraper/excavators, browsers, grazer/detritivores), while increasing biomass and abundance of territorial algal-farming damselfishes (Pomacentridae). The browser functional group that consumes macroalgae and can help to prevent coral–macroalgal phase shifts appears to be most susceptible to fishing. This fishing down the herbivore guild probably alters the effectiveness of these fishes in regulating algal abundance on reefs. Finally, data from remote and unfished locations provide important baselines for setting management and conservation targets for this important group of fishes.

The study of interfacial reactions of nickel thin films on GaAs

1983 ◽  
Vol 41 ◽  
pp. 156-157
Author(s):  
L.J. Chen ◽  
Y.F. Hsieh
Keyword(s):  
Thin Films ◽  
Integrated Circuits ◽  
Interfacial Reactions ◽  
Metal Contacts ◽  
Nickel Thin Films ◽  
Thin Foils ◽  
The Status ◽  
Si Doped ◽  
Electron Microscopes

One measure of the maturity of a device technology is the ease and reliability of applying contact metallurgy. Compared to metal contact of silicon, the status of GaAs metallization is still at its primitive stage. With the advent of GaAs MESFET and integrated circuits, very stringent requirements were placed on their metal contacts. During the past few years, extensive researches have been conducted in the area of Au-Ge-Ni in order to lower contact resistances and improve uniformity. In this paper, we report the results of TEM study of interfacial reactions between Ni and GaAs as part of the attempt to understand the role of nickel in Au-Ge-Ni contact of GaAs.N-type, Si-doped, (001) oriented GaAs wafers, 15 mil in thickness, were grown by gradient-freeze method. Nickel thin films, 300Å in thickness, were e-gun deposited on GaAs wafers. The samples were then annealed in dry N2 in a 3-zone diffusion furnace at temperatures 200°C - 600°C for 5-180 minutes. Thin foils for TEM examinations were prepared by chemical polishing from the GaA.s side. TEM investigations were performed with JE0L- 100B and JE0L-200CX electron microscopes.

Fate of sperm membrane in fertilized ova

1993 ◽  
Vol 51 ◽  
pp. 40-41
Author(s):  
Frank J. Longo
Keyword(s):  
Electron Microscopy ◽  
Electrical Activity ◽  
Sea Urchins ◽  
Morphological Changes ◽  
Integrated System ◽  
Electrophysiological Recording ◽  
Experimental Conditions ◽  
The Status ◽  
Sperm Membrane ◽  
Temporal And Spatial

Measurement of the egg's electrical activity, the fertilization potential or the activation current (in voltage clamped eggs), provides a means of detecting the earliest perceivable response of the egg to the fertilizing sperm. By using the electrical physiological record as a “real time” indicator of the instant of electrical continuity between the gametes, eggs can be inseminated with sperm at lower, more physiological densities, thereby assuring that only one sperm interacts with the egg. Integrating techniques of intracellular electrophysiological recording, video-imaging, and electron microscopy, we are able to identify the fertilizing sperm precisely and correlate the status of gamete organelles with the first indication (fertilization potential/activation current) of the egg's response to the attached sperm. Hence, this integrated system provides improved temporal and spatial resolution of morphological changes at the site of gamete interaction, under a variety of experimental conditions. Using these integrated techniques, we have investigated when sperm-egg plasma membrane fusion occurs in sea urchins with respect to the onset of the egg's change in electrical activity.

Revisiting the status of dental ethics instruction

2000 ◽  
Vol 64 (11) ◽  
pp. 772-774 ◽  
Author(s):  
JG Odom ◽  
PL Beemsterboer ◽  
TD Pate ◽  
NK Haden
Keyword(s):  
Ethics Instruction ◽  
The Status

The status of cosmology

2002 ◽  
Vol 110 (2) ◽  
pp. 9-15 ◽  
Author(s):  
W Freedman
Keyword(s):  
The Status

Multicultural Assessment of Personality and Psychopathology in the United States: Still Art, Not Yet Science, and Controversial

1998 ◽  
Vol 14 (1) ◽  
pp. 62-70 ◽  
Author(s):  
Richard H. Dana
Keyword(s):  
United States ◽  
Racial Identity ◽  
The United States ◽  
Therapeutic Assessment ◽  
Culturally Competent ◽  
Research Attention ◽  
The Status ◽  
Training Research ◽  
Multicultural Assessment ◽  
Personality Description

This paper describes the status of multicultural assessment training, research, and practice in the United States. Racism, politicization of issues, and demands for equity in assessment of psychopathology and personality description have created a climate of controversy. Some sources of bias provide an introduction to major assessment issues including service delivery, moderator variables, modifications of standard tests, development of culture-specific tests, personality theory and cultural/racial identity description, cultural formulations for psychiatric diagnosis, and use of findings, particularly in therapeutic assessment. An assessment-intervention model summarizes this paper and suggests dimensions that compel practitioners to ask questions meriting research attention and providing avenues for developments of culturally competent practice.

The Status of Psychiatric Research

1962 ◽  
Vol 7 (4) ◽  
pp. 156-156
Author(s):  
C. SHAGASS
Keyword(s):  
Psychiatric Research ◽  
The Status

A Perspective on the Status of Social Psychology

1990 ◽  
Vol 35 (10) ◽  
pp. 982-983
Author(s):  
Gail M. Williamson
Keyword(s):  
Social Psychology ◽  
The Status
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