Economic tradeoffs in the Gulf of Maine ecosystem: Herring and whale-watching

This research attempts to quantify some of the effects of localized depletion of herring by examining the search times of commercial whale-watching vessels. Whale-watching vessels are indirect users of herring; whales feed on herring and may disperse when prey availability is low. A dataset of daily whale-watching outcomes is combined with fishing effort and oceanographic data to test the hypothesis that intensive fishing effort increases the search time of whale-watching companies. Our results suggest that fishing may have a detrimental impact on search time; however, the magnitude of this effect is fairly small. We find policy that the recently enacted policy which prohibits fishing for herring in whale-watching areas would decrease search times by a small amount. We find some evidence of a localized aggregation effect; search times are the lowest when herring are spawning in the inshore areas. These results should be of interest to policymakers in determining future fishing regulations in an ecosystem-based fisheries management context.     

Distributional effects of property rights: Transitions in the Atlantic Herring fishery

A principal challenge in developing any fishery management plan is the allocation of benefits and costs among participants in the fishery. This process is further complicated by imperfect information about future market demand and limited ability to predict the consequences of regulatory change. This paper offers a new approach to policymakers, using econometric analysis to simulate the potential impact of individual tradable quotas (ITQs) in a fishery. We compare the distribution of harvest across participants in the Atlantic Herring fishery under the current open access regime and under a potential ITQ regime, assuming two different levels of future demand. Our results show that production efficiency varies by vessel gear, home-port and relationship with buyers. Some of the predicted consequences of ITQs are: vessels from Massachusetts will gain share relative to those from Maine; trawlers will gain share relative to purse seine vessels; and independent vessels will lose share relative to vessels that are primarily contracted to specific processors or bait companies. These results will help policymakers in developing future management plans for the herring fishery. More generally, this analytical approach can help regulators in any fishery assess the potential impact of alternative policy changes under alternative future demand scenarios.     

Stock Identification of Chum Salmon (<Emphasis Type="Italic">Oncorhynchus keta</Emphasis>) Using Trace Elements in Otoliths

The relationship between trace elements in chum salmon otoliths and in their rearing water was investigated to develop ways to distinguish chum salmon stocks in Korea. Rearing water and otoliths of hatchery-reared chum salmon fry were collected from three major hatcheries (Yangyang, Samchuk, and Uljin) on the east coast of Korea in spring 2001 and 2002. Trace elements in the otoliths and rearing water were analyzed using inductively coupled plasma mass spectrometry (ICP-MS) at the Korea Basic Science Institute. The chemical composition of rearing water and otoliths of the salmon fry at specific sites did not vary significantly through the study period. The ratios of some trace elements to Ca in rearing water, such as Sr/Ca and Ba/Ca, was clearly reflected in the chemical composition of otoliths, although the absolute concentrations were different. These two elements may be useful in distinguishing between salmon hatcheries, which have different chemical environments. Discriminant analysis with the ratios of eight elements to Ca (Na/Ca, Mg/Ca, Al/Ca, Cu/Ca, Sr/Ca, Ba/ Ca, Mn/Ca, and Zn/Ca) revealed a distinct separation of natal area in stocks. The analysis of otolith chemistry may be an effective technique for identifying the origins of wild salmon caught at sea.     

中国海域习见石斑鱼属鱼类矢耳石形态特征

以采自中国海域12种石斑鱼标本为基础,分析了石斑鱼属(Epinephelus)鱼类的矢耳石形态特征,探讨了耳石形态在该属鱼种识别方面的应用。结果显示,12种鱼类矢耳石形态近似,耳石细长,呈三角形或梭形,由听沟开口处形成的前部凹刻"V"形或浅宽,形成显著或不显著的侧叶。12种鱼耳石长宽比1.76~2.41,矩形趋近率0.60~0.72,充实度17.24~36.58。耳石外部轮廓、边缘光滑度、听沟前部形态、凹刻类型等特征同是本属鱼种耳石形态识别的主要依据,基于傅里叶系数的聚类分析结果表明耳石形态种间分异较显著。结果表明,听沟同是石斑鱼属鱼类耳石形态分类的重要特征之一,根据耳石形态可以实现石斑鱼属鱼种的初步分类检索,耳石形态在鱼类系统分类上有良好的应用研究前景。     

中国海域习见石斑鱼属鱼类矢耳石形态特征

以采自中国海域12种石斑鱼标本为基础,分析了石斑鱼属(Epine phelus)鱼类的矢耳石形态特征,探讨了耳石形态在该属鱼种识别方面的应用.结果显示,12种鱼类矢耳石形态近似,耳石细长,呈三角形或梭形,由听沟开口处形成的前部凹刻"V"形或浅宽,形成显著或不显著的侧叶,12种鱼耳石长宽比1.76～2.41,矩形趋近率0.60～0.72,充实度17.24～36.58.耳石外部轮廓、边缘光滑度、听沟前部形态、凹刻类型等特征同是本属鱼种耳石形态识别的主要依据,基于傅里叶系数的聚类分析结果表明耳石形态种间分异较显著.结果表明,听沟同是石斑鱼属鱼类耳石形态分类的重要特征之一.根据耳石形态可以实现石斑包属鱼种的初步分类检索,耳石形态在鱼类系统分类上有良好的应用研究前景.     

深海细菌Pseudomonas sp.bIp-2黑色素生成条件研究及其hppD基因的克隆

从大西洋深海沉积物中分离得到1株产黑色素细菌b Ip-2,16S rRNA基因序列分析表明该菌隶属于假单胞菌属（Pseudomonas）,与施氏假单胞菌（P.stutzeri）有最高的16S rRNA基因序列相似性（99%）.进一步对该菌的生长及产黑色素条件进行了初步研究,结果表明b Ip-2在稳定生长期后期才开始大量积累黑色素;b Ip-2可在4～37℃的温度范围下生长,最适生长温度为37℃,在28℃具有最高的黑色素产量;b Ip-2生长的pH范围偏碱性,在p H=7的最适生长条件下黑色素产量最高,同时碱性环境有利于黑色素的快速形成;b Ip-2可以在1%～9%的NaCl浓度范围中生长,在5%的NaCl浓度下具有最高的黑色素产量;低浓度的Fe^2＋（0.05 mmol/dm^3）可以提高黑色素的产量,Fe^2＋浓度≥0.20 mmol/dm^3时明显抑制黑色素的生成,而Fe^2＋浓度为1.00 mmol/dm^3时可完全抑制菌株的生长;低浓度的Cu^2＋（0.1 mmol/dm^3）对黑色素的产量无明显影响,Cu^2＋浓度≥0.5mmol/dm^3时可抑制黑色素的生成,而Cu^2＋浓度超过1.0 mmol/dm^3时可完全抑制菌株的生长.通过PCR扩增获得菌株b Ip-2的对羟苯基丙酮酸双加氧酶（hydroxyphenylpyruvic acid dioxygenase,HPPD）全长基因（1087 bp）,分析发现其编码的HPPD蛋白序列（含361氨基酸）与来自菌株Pseudomonas stutzeri RCH2的HPPD蛋白序列具有最高的同源性（序列相似性为97%）.这些结果为深入研究该细菌所产黑色素的合成,应用及生态作用奠定了基础.     

The Satellite Atmospheric Sounder IKFS-2: 2. Validation of the Temperature Sounding of the Atmosphere

Izvestiya, Atmospheric and Oceanic Physics - The validation of measurements of vertical temperature profiles by the IKFS-2 instrument (the Meteor-M no. 2 satellite) in cloudless conditions was...