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1.
大翅鲸     
大翅鲸,又称座头鲸,哺乳纲,鲸目,鳁鲸科。大翅鲸分布在全世界的海域,1属1种,是长须鲸的同类,在寒带和温带的海域生活,成年大翅鲸体长11~19米,身体、胸鳍、背面呈黑色,腹面呈白色,胸鳍特长,背面呈白色。下颚至腹部有20根左右平行的棱纹。它的皮肤常附着茗荷介及其蔓脚贝等。大翅鲸实行一夫一妻制,但常单独生活,怀孕期为12个月,一胎一子。刚出生的幼鲸体长4米,哺乳期为10  相似文献   

2.
黄海小鳁鲸生殖习性的研究   总被引:1,自引:0,他引:1  
王丕烈 《海洋与湖沼》1982,13(4):338-345
自1955年开始,作者对黄海北部捕获的小鳁鲸(Balaenoptera acutorostrata)的生物学特性做了一些调查,通过对陆地鲸体解剖所得胎儿的测定,以及在黄海中部的探捕,结合长期的海上实际观察,对黄海小鳁鲸的生殖习性进行了分析研究,现将结果报道如下。  相似文献   

3.
石浦海域齿鲸类一新纪录种记述   总被引:1,自引:0,他引:1  
首次记述了2002年9月9日在浙江省象山县石浦镇海滩上搁浅死亡的1头朗氏中喙鲸Mesoplodon pacificus Longman 1926,并对其外形和骨骼进行初步描述.体背部灰蓝色,体侧有白色斑点,腹部白色.下颌前端具1对向前倾的圆锥形牙齿.前颌骨后端显著向上隆起,并包裹在鼻骨的两侧,与额骨一起成为脑颅的最高点.上颌骨中部侧面明显向外隆起.7枚颈椎全部愈合.朗氏中喙鲸在我国大陆沿海属首次被发现.  相似文献   

4.
鲸目动物传统上大体分为两类:第一类包括鲸须鲸(小露脊鲸除外)和抹香鲸;第二类包括小齿鲸和海豚。鲸目动物分布于世界各个大洋,从北极到南极的海洋都有。有些品种是全球性的,其中包括较大的第一类鲸和商业上重要的品种——蓝鲤鲸、驼背鲸、长须鲸、鳁鲸、小鳁鲸、抹香鲸和虎鲸。海洋哺乳动物资源最容易捕捞过度,因为  相似文献   

5.
鲸鱼虽然名之曰“鱼”,而且“鲸”字也从“鱼”旁,但实际上却不是鱼类,而是用肺呼吸、胎生的哺乳动物。鲸鱼的种类颇多,分为齿鲸和须鲸两大类。鲸鱼一般以体型巨大者居多,“鲸”字从“京”,京为“大”意。《尔雅·释丘》说:“绝高为之京。”体型最大的要属须鲸中的蓝鳁鲸了,最大体长可达35米,体重可达190吨。鲸鱼体型如此巨大,古人航海时若遇到它的话,随时可能发生危险,让人不寒而栗。古人称雄鲸为鲸、雌鲸为鲵。又称鲸鱼为海鳅。因其体型巨大,可吞下古代的木船,故又称为吞舟之鱼。《太平御览》卷九三八引梁简文帝《金楼子》说:“鲸鲵一名海鳅。”《文选·左思·吴都  相似文献   

6.
鲸是生活在地球上最庞大的动物 ,其“大横海吞舟 ,出则水溢 ,入则潮涨”。完美的非常符合流体力学原理的纺锤形体型 ,使之能信步万里海浪 ,遨游千米水底 ,难怪古人曾幻想“骑鲸遁沧海”(苏轼 ) ,做“海上骑鲸客”(李白 ) ,或“欲跨长鲸临弱水 ,神州东去访蓬莱”(王枢 ) ,“此日骑鲸去 ,它年化鹤还”(赵蕃 )。人们对鲸的神往由此可见一斑。到了近代 ,随着科学技术的发展 ,世界各地相继建起了许多水族馆 ,其中最引人入胜的便是鲸豚、海豹、海狮等海兽类的展示和表演 :顶球 ,跳舞 ,飞越障碍物 ,与人握手或同游 ,等等。然而 ,最令人难忘的体验却…  相似文献   

7.
海狮与鲸     
人类至今对鲸的生活习性知之甚少,何故?因为迄今所获得的鲸的知识大多数是在船上观察的结果,而鲸一生中有5~6%的时间生活在海面;更重要的是,鲸对人造物十分敏感,只要在鲸的生活环境中引入人为因素,便立即打乱鲸社会的环境和行为。于是,科学家们想到了鲸的好友海狮。他们试图聘请海狮充当拍摄鲸的精彩生活的摄影师,以报道鲸的趣事秘闻。每当海洋生物学家詹齐格丽丝的身影悠然出现在圣克鲁兹海洋实验室的水池边时,人们便会发现4只极富人情味的海狮又跳又跃,兴高彩烈地迎接齐格丽丝。它们大吼大叫,鼻孔粗气直喘,以求主人的欢欣。海狮十分喜爱这位金发碧眼、肤色白皙  相似文献   

8.
<正>鲸是地球上最大的哺乳类动物,按照现代鲸类划分标准,鲸目不仅包括鲸,也包括海豚科、鼠海豚科和淡水豚总科。我国古人对鲸类的认识是根据鲸的外形特征将其归入到鱼类和鳞介之属。古代鲸的记载散见于沿海地方志,正史《五行志》对鲸的出没也有详细的记载,根据这些记载,考察不同历史时期鲸的分布及搁浅原因。《二十五史·五行志》中把鱼类的某些不常见现象都归入"鱼孽"中,由于鲸在近海极少见,且体形巨大,因此亦被归入鱼孽类,与当时的各种凶象联系  相似文献   

9.
鲸的介绍     
我们通常所说的鲸是指哺乳动物纲鲸目(Cetacean)下面除了我们常说的海豚、河豚和鼠海豚以外的所有大型海洋哺乳动物。它是所有哺乳动物中最适应水栖生活的一支,由于外形和鱼相似人们便习惯称它们为鲸鱼。鲸体呈流线或鱼雷形;颈不明显,自胸至尾浙细;体末端宽扁,尾鳍后缘有凹口,分左右两叶,为主要的运动器官:多数有背鳍,各鳍均由结缔组织与脂肪构成,内无  相似文献   

10.
蓝镜头     
《海洋世界》2010,(1):F0002-F0002
<正>驼背鲸母子在从波利尼西亚海域(幼鲸的出生地)迁往南极洲的长途旅途中。数百万年来,驼背鲸一直在海洋中繁衍生息,但是它们一直是一种神秘的海洋生物,人们对它们的生活方式及  相似文献   

11.
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   

12.
To track the diet of minke whale (Balaenoptera acutorostrata) in the East Sea (Japan Sea), a conjoint analysis of fatty acids and C and N stable isotopes was performed on blubber and skin from the whale and its potential prey. The total lipid content in the blubber of minke whales ranged from 37.9% to 82.7% of wet mass (mean ± SD, 63.1 ± 17.2%), with triacylglycerols being the dominant lipids (96.9%–99.2% of total lipids). The lipid and fatty acid (FA) contents were systematically stratified throughout the depth of the blubber layers; contents of the dominant monounsaturated FAs (MUFAs), including 18:1ω9 and 16:1ω7, increased from the innermost layer to the outermost layer, whereas contents of saturated FAs (SFAs) and polyunsaturated FAs (PUFAs) were higher in the innermost layer than in the outermost layer. This stratification is related to the different physiological roles of the blubber layers; e.g., thermoregulation, streaming, and buoyancy. A comparison of the FA compositions of the innermost layer of minke whales with those of potential prey indicates that FA compositions in the whales are similar to those of Pacific herring. In addition, stable isotope ratios (δ13C and δ15N) suggest that minke whale and Pacific herring have the same or similar diets. Therefore, the diets of minke whale from the East Sea (Japan Sea) could be inferred from information on the diet of the Pacific herring, although FA compositions and stable isotope ratios for Pacific herring would not exactly reflect the whale’s diet. Although the very limited number of samples was used in this study, our preliminary findings are very promising to help understand the feeding ecology of minke whales in the East Sea (Japan Sea).  相似文献   

13.
《Marine Policy》1998,22(2):161-174
The Norwegian minke whale hunt was resumed in 1993, despite considerable international opposition. This paper investigates economic aspects of the 1993–1996 hunts. It is shown that the hunts were profitable for the participating vessels. Adverse international effects due to the resumed hunt are discussed, as is the future of commercial whale hunting in Norway.  相似文献   

14.
The whales are an interesting group in several aspects of science, including evolutionary biology, marine ecology and toxicology. Some of the whale species, including the minke whale, graze at the top of the food chains, where they become susceptible to the accumulation of marine pollutants ingested by organisms at lower levels. The northern stock of the minke whale grazes in Arctic waters in the summer, an area of increasing interest in the development of new oil fields. Studies on the metabolism, disposition and effects of xenobiotics in marine mammals are few. The only reports in the open literature so far have dealt with these questions in seals.1–3 Although the marine mammals comprise a particularly interesting group in marine ecology and toxicology, no data have to our knowledge been presented on the xenobiotic metabolising enzyme systems of the whales. In this study, components of the microsomal cytochrome P-450 system were measured in liver samples from several females, one male, and two foetal minke whales, caught in the Norwegian whaling season of 1983. Because of the limited number of samples studied we have treated the samples individually and not performed any statistical analysis of the data. The trends discussed below must therefore be considered with this background.  相似文献   

15.
The Norwegian Sea is a migration and feeding ground for fin whales (Balaenoptera physalus) and humpback whales (Megaptera novaeangliae) in summer. During the last decade, significant structural changes in the prey community, including northerly expansion and movement in the distribution of pelagic fish species, have been reported from this ecosystem. However, little information on whale feeding ecology exists in the Norwegian Sea and surrounding waters. A total of 59 fin whales and 48 humpback whales were sighted during 864 h of observation over an observation distance of about 8200 nmi (15,200 km) in the Norwegian Sea from 15 July to 6 August 2006 and 2007. The fin whale group size, as mean (±SD), varied between one and five individuals (2.1 ± 1.2 ind.) and humpback whale group size varied between one and six individuals (2.5 ± 1.7 ind.). Fin‐ and humpback whales were observed mainly in the northern part of the study area, and were only found correlated with the presence of macro‐zooplankton in cold Arctic water. Humpback whales were not correlated with the occurrence of adult Norwegian spring‐spawning herring (Clupea harengus) except for the northernmost areas. Despite changes in the whale prey communities in the Norwegian Sea, no apparent changes in fin‐ or humpback whale distribution pattern could be found in our study compared to their observed summer distribution 10–15 years ago.  相似文献   

16.
Concentrations of 12 trace elements (V, Cr, Mn, Cu, Zn, Se, Rb, Sr, Cd, Cs, Ba, and Hg) were determined in liver and skin tissues of minke whales from various regions within the Antarctic Ocean. Cd concentrations in livers of southern minke whale were apparently higher than those in cetaceans from other regions, while Hg concentrations were lower. There were significant positive correlations between body length and concentrations of Cd and Hg in the liver. The concentrations of all trace elements in the skin were lower than those in other cetaceans reported previously. Significant positive correlations between liver and skin were found for Cr, Mn, Cu, Zn, Rb, Cd, and Cs, implying that the concentrations of these trace elements in the skin reflect those of internal organs. Large interannual variation of the accumulation pattern of trace elements in the skin was observed for the southern minke whales from Area V. There were significant differences in the skin element concentrations among Areas III, IV, and V, especially for males. Also, discriminant analysis between geographically two different groups collected during 1995/1996 austral summer season, based on the concentrations of trace elements in the skin, allowed for a correct classification of 90% of these minke whales. These results suggest that measurement of trace elements in skin samples could provide valuable information on the status of contamination and possible geographic differences in the accumulation levels in southern minke whales.  相似文献   

17.
The North Atlantic right whale (Eubalaena glacialis) is the most critically endangered large cetacean and is threatened by vessels that travel in their habitats and migration paths. A need to address the endangered population status of the right whale emerges as current management mandates have proven ineffective at preventing vessel-strikes to right whales and current rates of strike-induced mortality can slow or prevent recovery of the species. This paper identifies the need for an internationally acceptable management strategy to minimize vessel-strikes to right whales in Canadian waters.  相似文献   

18.
We describe gray whale (Eschrichtius robustus) distribution in the south-central Chukchi Sea in relation to environmental factors during two 5-day surveys in June and September of 2003. Whale counts per 10-min scan (an index of relative abundance) ranged from 0 to 41 in June and from 0 to 28 in September. CTD data showed an ocean front around 67.8°N with strong horizontal gradients in temperature, salinity, chlorophyll-a concentration and water-column stability. Highest whale abundance indices occurred in or near the front in both periods. Preliminary qualitative assessment of biological communities in the study area suggests that infaunal clams, echinoderms, euphausids, chaetognaths and Arctic cod were common, while ampeliscid amphipods, the previously abundant infauna (and likely prey) in the nearby Chirikov Basin feeding area, were not dominant. Euphausids may be a prey for gray whales in this area. We suggest that frontal systems may play an important role in eastern North Pacific gray whale foraging grounds. Further study is needed to fully describe the role of frontal systems in gray whale foraging grounds.  相似文献   

19.
The sequential megafaunal collapse hypothesis: Testing with existing data   总被引:4,自引:1,他引:4  
Springer et al. [Springer, A.M., Estes, J.A., van Vliet, G.B., Williams, T.M., Doak, D.F., Danner, E.M., Forney, K.A., Pfister, B., 2003. Sequential megafaunal collapse in the North Pacific Ocean: an ongoing legacy of industrial whaling? Proceedings of the National Academy of Sciences 100 (21), 12,223–12,228] hypothesized that great whales were an important prey resource for killer whales, and that the removal of fin and sperm whales by commercial whaling in the region of the Bering Sea/Aleutian Islands (BSAI) in the late 1960s and 1970s led to cascading trophic interactions that caused the sequential decline of populations of harbor seal, northern fur seal, Steller sea lion and northern sea otter. This hypothesis, referred to as the Sequential Megafaunal Collapse (SMC), has stirred considerable interest because of its implication for ecosystem-based management. The SMC has the following assumptions: (1) fin whales and sperm whales were important as prey species in the Bering Sea; (2) the biomass of all large whale species (i.e., North Pacific right, fin, humpback, gray, sperm, minke and bowhead whales) was in decline in the Bering Sea in the 1960s and early 1970s; and (3) pinniped declines in the 1970s and 1980s were sequential. We concluded that the available data are not consistent with the first two assumptions of the SMC. Statistical tests of the timing of the declines do not support the assumption that pinniped declines were sequential. We propose two alternative hypotheses for the declines that are more consistent with the available data. While it is plausible, from energetic arguments, for predation by killer whales to have been an important factor in the declines of one or more of the three populations of pinnipeds and the sea otter population in the BSAI region over the last 30 years, we hypothesize that the declines in pinniped populations in the BSAI can best be understood by invoking a multiple factor hypothesis that includes both bottom–up forcing (as indicated by evidence of nutritional stress in the western Steller sea lion population) and top–down forcing (e.g., predation by killer whales, mortality incidental to commercial fishing, directed harvests). Our second hypothesis is a modification of the top–down forcing mechanism (i.e., killer whale predation on one or more of the pinniped populations and the sea otter population is mediated via the recovery of the eastern North Pacific population of the gray whale). We remain skeptical about the proposed link between commercial whaling on fin and sperm whales, which ended in the mid-1960s, and the observed decline of populations of northern fur seal, harbor seal, and Steller sea lion some 15 years later.  相似文献   

20.
A unique whale call with 50–52 Hz emphasis from a single source has been tracked over 12 years in the central and eastern North Pacific. These calls, referred to as 52-Hz calls, were monitored and analyzed from acoustic data recorded by hydrophones of the US Navy Sound Surveillance System (SOSUS) and other arrays. The calls were noticed first in 1989, and have been detected and tracked since 1992. No other calls with similar characteristics have been identified in the acoustic data from any hydrophone system in the North Pacific basin. Only one series of these 52-Hz calls has been recorded at a time, with no call overlap, suggesting that a single whale produced the calls. The calls were recorded from August to February with most in December and January. The species producing these calls is unknown. The tracks of the 52-Hz whale were different each year, and varied in length from 708 to 11,062 km with travel speeds ranging from 0.7 to 3.8 km/h. Tracks included (A) meandering over short ranges, (B) predominantly west-to-east movement, and (C) mostly north-to-south travel. These tracks consistently appeared to be unrelated to the presence or movement of other whale species (blue, fin and humpback) monitored year-round with the same hydrophones.  相似文献   

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