小头鲔寄生鳍缨虫的分离及鉴定

海南陵水小型金枪鱼驯养基地在小头鲔(Euthynnus affinis)养殖过程中发现有寄生虫附着现象,文章对小头鲔寄生虫进行了分离、形态观察及18S、28S rRNA分子鉴定。结果显示,经18S rRNA分子鉴定,该寄生虫与Branchiomma sp.相似性为99.13%;而28S rRNA显示,该寄生虫与黑斑鳍缨虫B.nigromaculatum相似性为100%,与Branchiomma sp.(EF116223.1)相似性为99.12%。形态观察发现,该寄生虫虫体呈墨绿色、棕黄色或红棕色,具鳃冠,全长30~90 mm,寄生于小头鲔鳃弓后缘的体表及胸鳍中后部。该寄生虫由鳃冠、胸区和腹区组成,无钙质管,其消化道包括口、口腔、咽、肠、肛门等,与黑斑鳍缨虫存在少许生活习性和形态差别。因此,该寄生虫是否为鳍缨虫属(Branchiomma)、黑斑鳍缨虫(B.nigromaculatum),仍需进一步验证。该虫附着于小头鲔体表后,小头鲔摄食量明显下降,游泳速度加快,易受惊吓。采用甲醛浸泡具有良好的去除效果,去除后小头鲔成活率为75.9%。     

The pelagic habitat analysis module for ecosystem‐based fisheries science and management

We have developed a set of tools that operate within an aquatic geographic information system to improve the accessibility, and usability of remote‐sensed satellite and computer‐modeled oceanographic data for marine science and ecosystem‐based management. The tools form the Pelagic Habitat Analysis Module (PHAM), which can be applied as a modeling platform, an investigative aid in scientific research, or utilized as a decision support system for marine ecological management. Applications include fisheries, marine biology, physical and biological oceanography, and marine spatial management. The GIS provides a home for diverse data types and automated tools for downloading remote sensed and global circulation model data. Within the GIS environment, PHAM provides a framework for seamless interactive four‐dimensional visualization, for matching between disparate data types, for flexible statistic or mechanistic model development, and for dynamic application of user developed models for habitat, density, and probability predictions. Here we describe PHAM in the context of ecosystem‐based fisheries management, and present results from case study projects which guided development. In the first, an analysis of the purse seine fishery for tropical tuna in the eastern Pacific Ocean revealed oceanographic drivers of the catch distribution and the influence of climate‐driven circulation patterns on the location of fishing grounds. To support management of the Common Thresher Shark (Alopias vulpinus) in the California Current Ecosystem, a simple empirical habitat utilization model was developed and used to dynamically predict the seasonal range expansion of common thresher shark based on oceanographic conditions.     

金枪鱼加工及其综合利用现状与展望

介绍了金枪鱼鱼块、鱼片、罐头制品等的加工工艺以及其下脚料(包括鱼头、鱼骨、鱼皮和鱼内脏等)的开发利用现状,并对其进一步的研发进行了展望。     

Loggerhead turtle (Caretta caretta) bycatch in Canadian pelagic longline fisheries: Relative importance in the western North Atlantic and opportunities for mitigation

Little is known about the ecology of loggerhead turtles, Caretta caretta, in Canadian waters. However, Canada's eastern waters off the Scotian Shelf, Georges Bank and Grand Banks appear to be seasonal foraging habitats based on dates and locations where they have been captured as fishery bycatch. Estimates derived from data recorded by the international observer program (IOP) and used for this study suggest that thousands of mostly immature loggerheads have been captured in the Canadian pelagic longline fishery (PLF) in the western North Atlantic since 1999. These data suggest that the PLFs for tuna and swordfish are among the most important causes of incidental capture. Although U.S. and Canadian bycatch estimation methods differ and uncertainty associated with the estimates is high, it is clear from the IOP data that bycatch in the Canadian PLF is substantial and roughly within the same magnitude as that reported for the entire U.S. fleet in the North Atlantic for the same period (1999–2005). Analysis of bycatch observer data from the Canadian PLF and other empirical data suggests that fishing at temperatures below 20 °C using fish rather than squid bait and size-18 circle hooks could reduce loggerhead bycatch and mortality. However, research is needed to identify the best options and their commercial viability. Loggerheads that use Canadian Maritime waters are one of the least studied groups of loggerheads in the world, so systematic long-term studies on the ecology of loggerheads in Canada would help fill important information gaps and assist in developing effective recovery plans for this species.     

Large-scale experiment shows that nylon leaders reduce shark bycatch and benefit pelagic longline fishers

We assess the performance of wire leaders, which some jurisdictions have banned to reduce shark mortality from pelagic longline fishing. Experiments were conducted off northeastern Australia on commercial vessels that deployed equal numbers of wire and nylon monofilament leaders randomly along their longlines. Catch rates of several species, including sharks, were lower on nylon than on wire leaders, probably because those animals often escape by biting through the nylon leaders. High bite-off rates indicate that as many animals escape from nylon leaders as are caught on nylon leaders. The fate of escaped animals is not known, although large sharks are more likely to survive than are small animals. By contrast, catch rates of valuable bigeye tuna (Thunnus obesus) were higher on nylon than on wire leaders. Bigeye tuna are probably able to see wire leaders and avoid those hooks. The financial benefits of increased bigeye tuna catches outweigh the costs associated with banning wire leaders, such as increased rates of gear loss. Thus, banning wire leaders is an effective way of reducing shark catches that fishers should be keen to adopt.     

利用G IS分析中西太平洋金枪鱼围网渔场的时空变动

根据中西太平洋1984~2003年金枪鱼围网渔业的渔获量统计资料,利用G IS定性分析方法和数值分析方法对中西太平洋海区的金枪鱼围网渔场的时空变动进行研究。研究结果表明:1984年到1991年,CPUE值在12.0~17.3 t/(d.n)之间;1992年至2003年,CPUE值在19.1~27.9 t/(d.n)之间,两个阶段的CPUE差异显著;Ⅰ、Ⅱ和Ⅲ类渔场基本上全部分布在5°S~5°N、140°E~180°之间,但Ⅲ类渔场在南半球略往东延伸,在10~5°S、155°~160°E之间也有分布;Ⅳ、Ⅴ类渔场则分布在Ⅰ、Ⅱ和Ⅲ类渔场的周边,其中Ⅳ类渔场主要位于东经地区,Ⅴ类渔场主要位于西经地区。     

悬链线和抛物线理论在金枪鱼延绳钓渔业中的应用

本文依次用悬链线和抛物线理论分析推导了金枪鱼延绳钓具的两种投放方法以及在渔场各水层相同流态下钓具充分沉降后所有钓钩位置包括深度和相互间水平间距的计算公式 ,可用于作业参考。     

深冷型远洋金枪鱼延绳钓主要技术参数及作业参数的分析

金枪鱼延绳钓的技术参数和作业参数的选择对渔捞效果影响很大，对深冷型远洋金枪鱼延绳钓来说，延绳钓钩位深度是最重要的。本文中作者对主要技术参数、作业参数及它们之间的关系做了较详细的论述，对钓钩深度的确定和调整及其影响因素做了分析，并给出其计算方法。     

大西洋南部金枪鱼渔场的生产调查报告

根据随船调查材料，对大西洋南部金枪鱼延绳钓渔业从捕捞技术，渔场环境因素，渔获物情况、初加工、销售等方面做出了总结。本文着重分析了各个作业渔场的渔获情况，判断出八个中心渔场的位置，并就大眼金枪鱼在这几个中心渔场的生物学特征做了统计分析，从而为用地理信息技术预报渔场提供了实施依据。     

Incorporating spatial autocorrelation into the general linear model with an application to the yellowfin tuna (Thunnus albacares) longline CPUE data

Catch-per-unit-effort (CPUE) data have often been used to obtain a relative index of the abundance of a fish stock by standardizing nominal CPUE using various statistical methods. The theory underlying most of these methods assumes the independence of the observed CPUEs. This assumption is invalid for a fish population because of their spatial autocorrelation. To overcome this problem, we incorporated spatial autocorrelation into the standard general linear model (GLM). We also incorporated into it a habitat-based model (HBM), to reflect, more effectively, the vertical distributions of tuna. As a case study, we fitted both the standard-GLM and spatial-GLM (with or without HBM) to the yellowfin tuna CPUE data of the Japanese longline fisheries in the Indian Ocean. Four distance models (Gaussian, exponential, linear and spherical) were examined for spatial autocorrelation. We found that the spatial-GLMs always produced the best goodness-of-fit to the data and gave more realistic estimates of the variances of the parameters, and that HBM-based GLMs always produced better goodness-of-fit to the data than those without. Of the four distance models, the Gaussian model performed the best. The point estimates of the relative indices of the abundance of yellowfin tuna differed slightly between standard and spatial GLMs, while their 95% confidence intervals from the spatial-GLMs were larger than those from the standard-GLM. Therefore, spatial-GLMs yield more robust estimates of the relative indices of the abundance of yellowfin tuna, especially when the nominal CPUEs are strongly spatially autocorrelated.