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31.
祝茜 《中国海洋湖沼学报》1998,(3)
INTRODUCTIONThehoweadwhales(Bahaamyticeus)areveryiInPOrtantsPeciesinthetraditionandctiltmeoftheEskimoPeoPle,whohuntthemeveryyear,andhaveagredtoallowsomesPecimenstobecollectedfromharVested(forsubsistence)boweadwhalesforscien-tificresearehpUrpOses.StudiesontheothitofthebOweadwhalearefewandfarbetWeen.unanisANDMrmODTheorbitsofttheboweadwhaleskulls(87B6,9oB11,94B12)keptinNorthSlopeBorough,Barrow,Alaska,U.S.A.lwereobservedinsitu.asSULrsTheorbitisacavitywhichenclosestheeyeball,witht… 相似文献
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The contaminant-induced cytochrome P450 (CYP) members in minke whale (Balaenoptera acutorostrata) can be potential biomarkers of the contaminant exposure and toxic effects. In this study, we constructed a cDNA library from the liver of minke whale from the North Pacific, and further screened a total of 6930 clones randomly selected in the library for the isolation of cDNA clones encoding novel members of CYP superfamily. The screening revealed the isolation of six novel CYP cDNA clones that are classified into CYP1A, CYP2C, CYP2E, CYP3A, CYP4, and CYP4A subfamilies. The BLAST homology search using the partial cDNA fragments of four CYP subfamilies (CYP1A, CYP2C, CYP2E and CYP4A) demonstrated that the minke whale CYPs were most closely related to pig CYPs (81-91%). Identification of multiple CYP genes in marine mammal species such as minke whale will provide new insights into the metabolic or toxicological functions of individual CYP members. 相似文献
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In the final decades of the last century, an increasing number of strandings of male sperm whales (Physeter macrocephalus) around the North Sea led to an increase in public interest. Anthropogenic influences (such as contaminants or intensive sound disturbances) are supposed to be the main causes, but natural environmental effects may also explain the disorientation of the animals. We compared the documented sperm whale strandings in the period from 1712 to 2003 with solar activity, especially with sun spot number periodicity and found that 90% of 97 sperm whale stranding events around the North Sea took place when the smoothed sun spot period length was below the mean value of 11 years, while only 10% happened during periods of longer sun spot cycles. The relation becomes even more pronounced (94% to 6%, n = 70) if a smaller time window from November to March is used (which seems to be the main southward migration period of male sperm whales). Adequate chi-square tests of the data give a significance of 1% error probability that sperm whale strandings can depend on solar activity. As an alternative explanation, we suggest that variations of the earth's magnetic field, due to variable energy fluxes from the sun to the earth, may cause a temporary disorientation of migrating animals. 相似文献
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Large mysticete whales represent a unique challenge for chemical risk assessment. Few epidemiological investigations are possible due to the low incidence of adult stranding events. Similarly their often extreme life-history adaptations of prolonged migration and fasting challenge exposure assumptions. Molecular biomarkers offer the potential to complement information yielded through tissue chemical analysis, as well as providing evidence of a molecular response to chemical exposure. In this study we confirm the presence of cytochrome P450 reductase (CPR) and cytochrome P450 isoenzyme 1A1 (CYP1A1) in epidermal tissue of southern hemisphere humpback whales (Megaptera novaeangliae). The detection of CYP1A1 in the integument of the humpback whale affords the opportunity for further quantitative non-destructive investigations of enzyme activity as a function of chemical stress. 相似文献
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观鲸旅游业在国外发展迅速,已成为尊重海洋动物权益、满足海洋旅游者“原真体验”需求的重要手段。本文对国外观鲸旅游的研究范畴和关注重点进行研究,力图为我国观鲸旅游业的健康发展提供经验借鉴和理论指导。目前国际观鲸旅游业的观赏对象以鲸目动物和鲸鲨为主,侧重于对观鲸旅游活动开展对海洋生物习性、行为模式的影响研究,在经营管理方面的研究侧重依观鲸旅游业开展的成熟与否而有所差别。 相似文献
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Reports of anomalously pigmented cetaceans, including melanistic (all‐black) individuals are infrequent. We observed four melanistic southern right‐whale dolphins (Lissodelphis peronii) including a calf, off Kaikoura (42°34'S, 173°50'E), New Zealand. We also compiled records of melanistic individuals from five other species of cetaceans. The ecological context of melanistic pigmentation of cetaceans is not well understood; however, it may increase heat absorption, affect ability to capture prey, impair visual/social communication, and/or increase conspicuousness to predators. 相似文献
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南极小须鲸(Balaenopterabonaerensis)作为顶级捕食者,在南大洋生态系统中起着重要调节作用。目前对南极小须鲸的研究大多集中在捕食和季节性迁移上,在栖息地分布以及气候变化对栖息地影响方面研究亟待补充。基于MaxEnt模型和CMIP6的数据,分析了当前情形以及不同排放情景下,到21世纪中期和21世纪末期宇航员海南极小须鲸栖息地的分布和变化。研究结果表明,南极小须鲸主要分布在宇航员海的东部,当前的高度适生区占整个区域的13.96%。深度、海冰密集度和混合层深度最小值是南极小须鲸分布的主要影响因子,三者的累积贡献为60.5%。气候变化情景下南极小须鲸栖息地呈现缩小的趋势。高排放情景下南极小须鲸的栖息地面积减小更快,从21世纪中期到末期这个时期南极小须鲸的栖息地面积减小速率比从当前到21世纪中期快。到本世纪中期,所有情景下的宇航员海东部仍存在南极小须鲸的栖息地;到本世纪末,中排放情景和高排放情景下的宇航员海已不适合南极小须鲸生存,海冰密集度的减小是造成这一现象的主要原因。 相似文献