Influence of fishers’ behaviour on the catchability of surface tuna schools in the Venezuelan purse-seiner fishery in the Caribbean Sea

1999 ◽  
Vol 56 (3) ◽  
pp. 394-406
Author(s):  
Daniel Gaertner ◽  
Mauricio Pagavino ◽  
Jesus Marcano
Keyword(s):  
Environmental Factors ◽  
Daily Activity ◽  
Caribbean Sea ◽  
Catch Rate ◽  
Causal Network ◽  
Fine Scale ◽  
Network Approach ◽  
Logistic Regressions ◽  
The Caribbean ◽  
The Impact

The influence of Venezuelan skippers' behaviour on the catchability of surface tuna schools was modelled using logistic regressions. Data obtained from observers onboard purse seiners indicated that fishers' fine-scale decisions, such as chasing and setting a school, were influenced by (i) the skipper's skill, (ii) the fishing equipment used (e.g., whether a bird radar was used or not), (iii) the features of the tuna school, and (iv) some environmental factors. The connections among the decisions related to the fishing process and these variables were synthesized in a causal network approach. Results clearly showed that schools (i) composed by fishes under 2 kg and (ii) where biomass was lower than 5 metric tons were disregarded by fishers. Because fishers used these thresholds to decide when to set the net, modifications in their behaviour over the years may introduce serious biases in the analysis of any catch rate and abundance relationship. An average daily activity record of a purse seiner shows the proportion of time spent in searching and in setting activities and highlights the impact that the use of new fishing equipment may have on fishing power.

scholarly journals Arribazones de Sargassum en la costa norte occidental de Cuba

2020 ◽  
Vol 2 (1) ◽  
pp. 19-30
Author(s):  
G. Arencibia-Carballo ◽  
J.M. Irañeta Batallán ◽  
J. Morell ◽  
A.R. Moreira González
Keyword(s):  
Negative Impact ◽  
Caribbean Sea ◽  
Geographic Area ◽  
Tourism Industry ◽  
Caribbean Region ◽  
Western Coast ◽  
Tidal Zone ◽  
The North ◽  
The Caribbean ◽  
The Impact

The pelagic macroalgae finches of the Sargassum genus in the Caribbean Sea currently represent a very natural problem due to their negative impact on the tourism industry, fishing industry, the environment and society in general. This work presents an above report of Sargassum that occurred on the north western coast of the Cuban archipelago in March 2019. The macroalgae species identified in the tidal zone were Sargassum fluitans and S. natans, and the specific geographic area where the impact of the upheaval occurred was from the west of Matan-zas bay to Mariel bay. The finches of these macroalgae were cataloged with a moderate magnitude compared to other reports in the Mexican Caribbean and in the Dominican Republic. This order of magnitude was cataloged based on its covered area of 169.3 km and its distribution along the coast in large patches, but very fragmented, despite the prevailing winds from the first quadrant (from north to east) during this period. Other events of this type reported in Cuba and the Caribbean region are taken up and discussed. Keywords: Caribbean Sea, Sargassum fluitans, Sargassum natans, Cuba.

scholarly journals On the Impact of the Caribbean Counter Current in the Guajira Upwelling System

2021 ◽  
Vol 8 ◽  
Author(s):  
Alejandro Orfila ◽  
Claudia P. Urbano-Latorre ◽  
Juan M. Sayol ◽  
Stephanie Gonzalez-Montes ◽  
Alejandro Caceres-Euse ◽  
...  
Keyword(s):  
Ocean Circulation ◽  
Caribbean Sea ◽  
High Concentration ◽  
Near Surface ◽  
Relaxation Phase ◽  
Upwelling System ◽  
South Central ◽  
The Caribbean ◽  
Counter Current ◽  
The Impact

The variability of La Guajira upwelling system, in the south-central Caribbean Sea, is strongly influenced by the intensity and location of the atmospheric Caribbean Low-Level Jet (CLLJ), a near-surface branch of the easterlies, as well as by the regional ocean circulation. During favorable conditions (i.e., strong easterlies blowing almost parallel to the coast), upwelling is enhanced and a large amount of primary productivity occurs in La Guajira area. In contrast, during relatively mild wind conditions, the CLLJ is misaligned to the coast and the Caribbean Counter Current (CCC, locally also known as the Darien Current), which forms as a branch from the Panama-Colombia Gyre, flows northeastward over the continental shelf advecting waters from the southwestern Caribbean basin toward La Guajira. The CCC has a clear signature at the surface layer that extends from the Darien Gulf toward La Guajira peninsula during mild wind periods, while disappears during the months of strong winds. The direction and the magnitude of the easterlies, and more specifically of the CLLJ, control the position and pathway of the CCC, which extends more than 900 km in the southern Caribbean Sea during May, June, August, September, and October. The high concentration of chlorophyll-a at the sea surface evidenced by satellite-based color images is semi-seasonally modulated by the CLLJ, which during its relaxation phase allows the irruption of the CCC toward the east up to La Guajira.

scholarly journals The impact of upwelling on the intensification of anticyclonic ocean eddies in the Caribbean Sea

Ocean Science ◽  
2019 ◽  
Vol 15 (6) ◽  
pp. 1419-1437 ◽  
Author(s):  
Carine G. van der Boog ◽  
Julie D. Pietrzak ◽  
Henk A. Dijkstra ◽  
Nils Brüggemann ◽  
René M. van Westen ◽  
...  
Keyword(s):  
Coastal Upwelling ◽  
Caribbean Sea ◽  
Vertical Shear ◽  
Ekman Transport ◽  
Density Gradients ◽  
River Plumes ◽  
Salinity Gradients ◽  
The Caribbean ◽  
Anticyclonic Eddies ◽  
The Impact

Abstract. The mesoscale variability in the Caribbean Sea is dominated by anticyclonic eddies that are formed in the eastern part of the basin. These anticyclones intensify on their path westward while they pass the coastal upwelling region along the Venezuelan and Colombian coast. In this study, we used a regional model to show that this westward intensification of Caribbean anticyclones is steered by the advection of cold upwelling filaments. Following the thermal wind balance, the increased horizontal density gradients result in an increase in the vertical shear of the anticyclones and in their westward intensification. To assess the impact of variations in upwelling on the anticyclones, several simulations were performed in which the northward Ekman transport (and thus the upwelling strength) is altered. As expected, stronger (weaker) upwelling is associated with stronger (weaker) offshore cooling and a stronger (weaker) westward intensification of the anticyclones. Moreover, the simulations with weaker upwelling show farther advection of the Amazon and Orinoco River plumes into the basin. As a result, in these simulations the horizontal density gradients were predominantly set by horizontal salinity gradients. The importance of the horizontal density gradients driven by temperature, which are associated with the upwelling, increased with increasing upwelling strength. The results of this study highlight that both upwelling and the advection of the river plumes affect the life cycle of mesoscale eddies in the Caribbean Sea.

Impact of the Global Gag Rule

2018 ◽  
Author(s):  
Yana van der Meulen Rodgers
Keyword(s):  
Developing Countries ◽  
Sub Saharan Africa ◽  
Before And After ◽  
Logistic Regressions ◽  
Health Survey Data ◽  
The Caribbean ◽  
The Difference ◽  
Sub Saharan ◽  
Low Exposure ◽  
The Impact

Chapter 6 offers new econometric estimates of the impact of the global gag rule on abortion rates. The analysis identifies the policy impact as the difference in abortion rates before and after the 2001 policy reinstatement and the difference between countries with high and low exposure to the policy. Abortion rates are constructed using Demographic and Health Survey data from 51 developing countries. Results from logistic regressions indicate that the global gag rule is associated with a threefold increase in the odds of women getting an abortion in Latin America and the Caribbean, a twofold increase in sub-Saharan Africa, and no net change in the Middle East and Central Asia. Results also indicate no consistent relationship between strict abortion laws and abortion rates. In the majority of developing countries exposed to the global gag rule, the policy failed to achieve its objective of discouraging women from getting an abortion.

scholarly journals The Impact of Upwelling on the Intensification of Anticyclonic Ocean Eddies in the Caribbean Sea

2019 ◽  
Author(s):  
Carine G. van der Boog ◽  
Julie D. Pietrzak ◽  
Henk A. Dijkstra ◽  
Nils Brüggemann ◽  
René M. van Westen ◽  
...  
Keyword(s):  
Coastal Upwelling ◽  
Caribbean Sea ◽  
Vertical Shear ◽  
Ekman Transport ◽  
Density Gradients ◽  
River Plumes ◽  
The Caribbean ◽  
Western Side ◽  
Anticyclonic Eddies ◽  
The Impact

Abstract. The mesoscale variability in the Caribbean Sea is dominated by anticyclonic eddies that are formed in the eastern part of the basin. These anticyclones intensify on their path westward while they pass the coastal upwelling region along the Venezuelan and Colombian coast. In this study, we used a regional model to show that this westward intensification of Caribbean anticyclones is driven by the advection of cold upwelling filaments. These dense filaments are advected by the anticyclones, leading to an increase of the horizontal density gradients at the western side of the anticyclones. Following the thermal wind balance, the increased density gradients result in an increase of the vertical shear of the anticyclones and to their westward intensification. To assess the impact of variations in upwelling on the anticyclones, several simulations were performed in which the northward Ekman transport (and thus the upwelling strength) is altered. As expected, stronger (weaker) upwelling is associated with more stronger (weaker) offshore cooling and a more (less) westward intensification of the anticyclones. The simulations with weaker upwelling show farther advection of the Amazon and Orinoco River plumes into the basin. The dispersion of the river plumes affects the formation process of the anticyclones, where the horizontal density gradients were mainly determined by the salinity gradients of the river plume and not by temperature gradients that were associated with upwelling.

Assessing the sustainability of the Siberian Federal District regions

2020 ◽  
Vol 18 (5) ◽  
pp. 891-908
Author(s):  
T.A. Smirnova
Keyword(s):  
Sustainable Development ◽  
Environmental Factors ◽  
Regional Development ◽  
Federal District ◽  
Integrated Approach ◽  
Siberian Federal District ◽  
The Sustainable Development ◽  
The Impact ◽  
Empirical Analyses

Subject. This article deals with the issues of functioning of the region as a system. Objectives. The article aims to identify the problems of the region's functioning as a system, develop methodological tools to monitor the sustainable development of the Siberian Federal District territories, and determine the the impact of socio-economic and environmental factors on the sustainable development of the region as a whole. Methods. For the study, I used the methods of theoretical, statistical, and empirical analyses taking into account an integrated approach. Results. The article reveals the impact of some individual components of regional development on the sustainability of the territorial system as a whole. Relevance. The results of the study can be used to analyze the sustainability of regions' development.

Directions of Accounting Environmental Factors for Forecasting Formation of Agroecosystems

2020 ◽  
pp. 31-35
Author(s):  
L.Z. Khalishkhova ◽  
◽  
A. Kh. Temrokova ◽  
I.R. Guchapsheva ◽  
K.A. Bogаtyreva ◽  
...  
Keyword(s):  
Sustainable Development ◽  
Comparative Analysis ◽  
Environmental Factors ◽  
Environmental Safety ◽  
Logical Analysis ◽  
Management Decisions ◽  
The Sustainable Development ◽  
The Impact

Ensuring the sustainable development of agroecosystems requires research into the justification of the impact of environmental factors on the formation of territorial agroecosystems and identifies ways to take them into account in order to justify management decisions and ensure environmental safety. The main goal of the research within the article is to identify the most significant environmental factors in predicting the formation of agroecosystems. Provisions are devoted to the study of the laws governing the functioning of agroecosystems in order to increase their stability. The methods of comparative analysis, generalization, abstraction, logical analysis are applied. A number of provisions are formulated regarding ways to account for the influence of factors on the formation of key elements of agroecosystems.

scholarly journals Effect of the Information Support Robot on the Daily Activity of Older People Living Alone in Actual Living Environment

2021 ◽  
Vol 18 (5) ◽  
pp. 2498
Author(s):  
Jumpei Mizuno ◽  
Daisuke Saito ◽  
Ken Sadohara ◽  
Misato Nihei ◽  
Shinichi Ohnaka ◽  
...  
Keyword(s):  
Cognitive Function ◽  
Older People ◽  
Daily Activity ◽  
Living Environment ◽  
Living Alone ◽  
Information Support ◽  
Sleep Patterns ◽  
High Cognitive Function ◽  
Environment Study ◽  
The Impact

Information support robots (ISRs) have the potential to assist older people living alone to have an independent life. However, the effects of ISRs on the daily activity, especially the sleep patterns, of older people have not been clarified; moreover, it is unclear whether the effects of ISRs depend on the levels of cognitive function. To investigate these effects, we introduced an ISR into the actual living environment and then quantified induced changes according to the levels of cognitive function. Older people who maintained their cognitive function demonstrated the following behavioral changes after using the ISR: faster wake-up times, reduced sleep duration, and increased amount of activity in the daytime (p < 0.05, r = 0.77; p < 0.05, r = 0.89, and p < 0.1, r = 0.70, respectively). The results suggest that the ISR is beneficial in supporting the independence of older people living alone since living alone is associated with disturbed sleep patterns and low physical activity. The impact of the ISR on daily activity was more remarkable in the subjects with high cognitive function than in those with low cognitive function. These findings suggest that cognitive function is useful information in the ISR adaptation process. The present study has more solid external validity than that of a controlled environment study since it was done in a personal residential space.

scholarly journals Impact of COVID-19 on workload burden of a complex radiotherapy facility

2021 ◽  
Vol 126 (5) ◽  
pp. 717-721
Author(s):  
Giulio Francolini ◽  
Isacco Desideri ◽  
Giulia Stocchi ◽  
Lucia Pia Ciccone ◽  
Viola Salvestrini ◽  
...  
Keyword(s):  
Disease Transmission ◽  
Daily Activity ◽  
Preventive Measures ◽  
Health Workers ◽  
Treatment Delivery ◽  
Actual Time ◽  
Italian Government ◽  
Significant Difference ◽  
The Impact ◽  
Observation Period

Abstract Background and purpose COVID-19 constitutes a worldwide threat, prompting Italian Government to implement specific measures on March 8, 2020, to protect patients and health workers from disease transmission. The impact of preventive measures on daily activity of a radiotherapy facility may hamper the ability to fulfill normal workload burden. Thus, we assessed the number of delivered treatments in a specific observation period after the adoption of preventive measures (since March 11 to April 24, 2020) and compared it with the corresponding period of the year 2019. Materials and methods Overall number of delivered fractions was related to actual time of platform daily activity and reported as a ratio between number of delivered fractions and activity hours (Fr/Hrs). Fr/Hrs were calculated and compared for two different periods of time, March 11–April 24, 2019 (Fr/Hrs1), and March 11–April 24, 2020 (Fr/Hrs2). Results Fr/Hrs1 and Fr/Hrs2 were 2.66 and 2.54 for year 2019 and 2020, respectively, for a Fr/Hrsratio of 1.07 (95% CI 1.03–1.12, p = 0.0005). Fr/Hrs1 was significantly higher than Fr/Hrs2 for SliR and PreciseR, with Fr/Hrsratio of 1.92 (95% CI 1.66–2.23, p < 0.0001) and 1.11 (95% CI 1.03–1.2, p = 0.003), respectively. No significant difference was reported for SynergyR and CyberknifeR with Fr/Hrsratio of 0.99 (95% CI 0.91–1.08, p = 0.8) and 0.9 (95% CI 0.77–1.06, p = 0.2), respectively. Fr/Hrs1 was significantly lower than Fr/Hrs2 for TomotherapyR, with Fr/Hrsratio of 0.88 (95% CI 0.8–0.96, p = 0.007). Conclusion Preventive measures did not influence workload burden performed. Automation in treatment delivery seems to compensate effectively for health workers number reduction.

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