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Species composition and diversity of pelagic fishes based on a longline fishery catch in the North Pacific Ocean

Chinese Journal of Oceanology and Limnology 2011年第2期29卷 261-269页

作者：朱江峰戴小杰陈勇 College of Marine Sciences Shanghai Ocean University The Key Laboratory of Sustainable Exploitation of Oceanic Fisheries Resources Ministry of Education School of Marine Sciences University of MaineOronoME 04469USA

Evaluation of spatial-temporal variability of species composition and diversity in oceanic ecosystems is not easy because it is usually difficult to obtain sufficient data quantifying such *** this study,we examined pelagic species diversity indicators,species richness,Shannon-Wiener index of diversity and Hurlbert's species evenness,for fish assemblages from two areas(north and south) in the North Pacific Ocean(2°±12°N,178°E±165°W) during May±July *** assemblages were based on data collected by an onboard scientific observer during a commercial longline fishing *** species richness and Shannon-Wiener diversity index of fish assemblages in the northern area were slightly higher than those in the southern area,although these differences were not significant(t test,P.0.05).Non-parametric multidimensional scaling and analysis of similarities indicated that there were significant differences in fish assemblages between the two areas(P,0.01).

关键词： species composition diversity pelagic fish longline North Pacific Ocean

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Dynamic Simulation of Pelagic longline Retrieval

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Journal of Ocean University of China 2019年第2期18卷 455-466页

作者： SONG Liming QI Yukun LI Jie SHEN Zhibin ZHANG Xinfeng SHEN Xi College of Marine Sciences Shanghai Ocean University National Engineering Research Centre for Oceanic Fisheries Shanghai Ocean University Key Laboratory of Sustainable Exploitation of Oceanic Fisheries Resources (Shanghai Ocean University) Ministry of Education Collaboration Innovation Center for National Distant-Water Fisheries

To improve fishing gear efficiency, it is important to understand the interactions among sea current, fishing vessel, line hauler, and catches during pelagic longline gear retrieval. In this study, fishing gear configuration parameters, operational parameters, and 3 D ocean current data were collected from Indian Ocean. Dynamic models of pelagic longline gear retrieval were built using the lumped mass method and solved using the Euler-Trapezoidal method. From the results, the pulling force of line hauler exerted on the gear was 2800–3600 N. There were no significant differences(P > 0.05) between the time of the hook retrieval measured at sea and that obtained from the simulation. The absolute values of the movement velocity at representative nodes along the X, Y, and Z axes were 0.01–25.5 m s^(-1). These results suggest that the dynamic model of longline fishing gear retrieval can be used to analyze the interactions among sea current, fishing vessel, line hauler, longline gear, and catches, and to acquire the basic data for optimizing the design of the line hauler. Moreover, the model can serve as a reference to study the hydrodynamic performance of other fishing gears during the hauling process.

关键词： pelagic longline retrieval dynamic simulation visualization

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The Development and Operational Testing of an Underwater Bait Setting System to Prevent the Mortality of Albatrosses and Petrels in Pelagic longline Fisheries

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Open Journal of Marine Science 2015年第1期5卷 1-12页

作者： Graham Robertson Phillip Ashworth Peter Ashworth Ian Carlyle Steven G. Candy Australian Antarctic Division Kingston Australia Amerro Engineering Warana Australia

longline fisheries for tunas and tuna-like species present an existential threat to many populations of albatrosses and petrels worldwide. To prevent this form of mortality we developed a new technology designed to deploy baited hooks underwater beyond the dive depths of?seabirds (6 - 10 m for the species most commonly caught). The underwater bait setter is a stern-mounted, hydraulically-operated and computer-controlled?device that catapults?baited hooks underwater in a steel capsule?connected to hydraulic winches by Spectra®rope. Baits are flushed from the capsule by water pressure through a spring-loaded bait release door. The chief engineering challenges in the developmental stageswere ensuring:?1) bait delivery?to target depths with cycle times (time from release to recovery) that were practical for fishing operations;?2) bait retention in the capsule (no drop-outs) on the descent phase of the cycle;?3) baits, upon?release at target depth, were not drawn up the water column on the capsule recovery phase (from possible hook-ups and/or suction);and?4) the retention of baits?on?hooks post-release from the capsule was not affected by the mechanical release underwater. Operational trials with the final version of the capsule yielded?satisfactory cycle times to depths of 6 - 10 m. All baits were retained?in the capsule on the descent and?released as required?at target depths (n = 606 deployments). Bait retention on hooks post release from the capsule and retention on hooks hand-set at the surface (the conventional method) were statistically indistinguishable.?The underwater bait setter is modular in construction and can be fitted to all types of vessel sterns.

关键词： Seabird Bycatch longline Fisheries Underwater Setting Marine Engineering Innovation Co-Operative Research

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Modeling the Hook Depth Distribution of Pelagic Longlining in the Equatorial Area of Indian Ocean

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Journal of Ocean University of China 2012年第4期11卷 547-556页

作者： SONG Liming LI Jie GAO Panfeng ZHOU Ji XU Liuxiong National Engineering Research Centre for Oceanic Fisheries ShanghaiOcean UniversityShanghai 201306P.R.China Key Laboratory of Sustainable Exploitation of Oceanic Fisheries Resources of Chinese Ministry of Education College of Marine SciencesShanghai Ocean UniversityShanghai 201306P.R.China College of Marine Sciences Shanghai Ocean UniversityShanghai 201306P.R.China Lianyunggang Fishery Detachment Lianyunggang 222004P.R.China

A survey was conducted in the equatorial area of Indian Ocean for a better understanding of the dynamics of hook depth distribution of pelagic longline fishery. We determined the relationship between hook depth and vertical shear of current coefficieney, wind speed, hook position code, sine of wind angle, sine of angle of attack and weight of messenger weight. We identified the hook depth models by the analysis of covariance with a general linear model. The results showed that the wind effect on the hook depth can be ignored from October to November in the survey area; the surface current effect on the hook depth can be ignored; the equato- rial undercurrent is the key factor for the hook depth in Indian Ocean; and there is a negative correlation between the hook depth and vertical shear of current and angle of attack. It was also found that the deeper the hook was set, the higher hook depth shoaling was. The proposed model improves the accuracy of the prediction of hook depth, which can be used to estimate the vertical distribution of pelagic fish in water column.

关键词： hook depth longline temperature-depth-recorder equatorial area the Indian Ocean

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Integrated habitat index for bigeye tuna(Thunnus obesus) in Marshall Islands waters based on quantile regression

Integrated habitat index for bigeye tuna(Thunnus obesus) in ...

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中国工程院第77场工程科技论坛·2008水产科技论坛——渔业现代化与可持续发展

作者： ZHANG Yu~1,SONG Li-ming~2 (1.East China Sea Fisheries Research Institute,Chinese Academy of Fishery Sciences,Shanghai 200090,China 2.College of Marine Science & Technology,Shanghai Ocean University,Shanghai 200090,China)

Bigeye tuna(Thunnus obesus)is one of the most important fish species in Marshall Islands *** is a growing need to describe the spatial extent and suitability of bigeye tuna habitats. A common approach to that is to construct spatially explicit habitat models from fisheries-independent survey data.A survey on tuna fishing ground was carried out in Marshall Islands waters from Oct, 2006 to May,*** tuna’ s catch rates(inds per 1 000 hooks)in each fishing day were calculated. The depth at which each bigeye tuna was hooked was estimated using a stepwise regression analysis of theoretical hook depth and observed average hook depth measured using a temperature depth *** temperature,salinity,dissolved oxygen and thermocline,which are important environmental variables influencing bigeye tuna habitats,were measured in the *** regression was used to estimate the maximum extent and suitability of bigeye tuna habitats,*** potential or upper limits of the habitat,in Marshall Islands *** in bigeye tuna’ s catch rates according to changes in environmental variables was estimated using regression quantiles,BLOSSOM statistical software was used to estimate regression quantile parameters,and backward elimination method was used to select significant environmental variables affecting bigeye tuna *** integrated habitat index(IHI)varying from 0 to 1 was developed to describe suitability of bigeye tuna habitats in different *** maps of bigeye tuna were also built using ARCGIS *** IHI model was validated by comparing predicted relative abundances against independent catch rates data of the commercial fishing fleet of China’s mainland fished in Marshall Islands waters from 2006 to 2007. Modelling the upper bounds of relationships between bigeye tuna and its habitat enables the detection of the effects of limiting factors on bigeye tuna’ s responses,and therefore this work have subsequent benefits for bigeye tuna’ s

关键词： bigeye tuna integrated habitat index longline quantile regression Marshall Islands waters.

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