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1.
利用耳石作为欧氏六线鱼年龄鉴定材料,结果表明耳石上的轮纹每年形成一次,即年轮。主要形成期是10月至翌年2月。提出耳石径与体长的关系式、体长和体重的关系式。指出相对增长率和生长指标反映了生长各阶段的特点。并给出生长参数。  相似文献   

2.
带鱼不同出生季节的鉴别   总被引:4,自引:1,他引:4  
在带鱼Trichiurus haumela(Porsk(?)l)的年龄鉴定中,关于耳石第一个年轮问题,国内外尚存在着争论。三栖宽(1958)认为:带鱼出生后18个月耳石形成第一个轮纹,并推测在观察到的第一个轮纹前还存在一个理论轮,在计数年龄时还应加1岁。近年的研  相似文献   

3.
水族寿星     
前不久在瑞典赫尔辛基水族馆里,举行了一次别开生面的“追悼会”,数百名衣冠楚楚的社会名流,为一条88岁高龄的鳗鲡突然死亡,甚感痛惜。主持人是这条鳗鲡的主人,他说:“它只活了寿限的三分之一!”无独有偶。最近,英国“挑战者”号考察船,在太平洋马里亚纳海沟取样考察时,偶然捕获了一条罕见的蛇。经专家鉴定:这是一条绿茸线蛇,已渡过了1 600多个春秋了! 这两位水族“寿星”的年龄是怎样测得的呢?我们知道,动物的鳞片、牙齿、耳石及外壳上,都有明显的“轮纹”。所谓“轮纹”就跟树木的“年轮”差不多。不过,动物的轮纹不象树木的那样清晰可见,有的还需借助显微镜才能观察到。这种“轮纹”既是动物的“年龄表”,又是当地水文气象的“活档案”。因为,每年春夏两季,动物的生长速度快,所长成的轮纹就宽;冬秋季节生长慢,轮纹就窄,由宽轮纹和窄轮纹组成的“同心轮”,就是它们的“年轮”。赫尔辛基水族馆的那条鳗鲡,牙齿上有88个年轮,“挑战者”,号捕捉的绿茸线蛇,从头到尾共有1 678个轮圈。从绿茸线蛇的生长规律推算,这条蛇的寿命可长达12万年!为此,人们兴致勃勃地为它安排了新的“住宅”,希望它寿比南山,同天地并存!  相似文献   

4.
年轮,显示了树木生长的年龄。海洋生物,特别是海洋动物是否也有年轮呢?科学家回答:有……鳞片青鱼、草鱼、鲤鱼、鲢鱼等多数鱼类,可以用鳞片来推算年龄。因为鱼鳞也象树木一样有年轮。这是由于鱼的年龄增长了,鳞片也会随之生长。如果仔细观察,你可以看到在鱼鳞片的上面,有许多同心的环纹。这环纹仿佛树木横断面上的环纹一样,叫做年轮。鱼类的年轮是怎样形成的呢?原来鱼类在春夏时节,食物丰富,生长旺盛,鳞片生长加快,产生很亮很宽的同心圈。同心圈的距离远,叫做夏轮,在秋冬季节,食物较少,生长也就缓慢,鳞片生长也就缓慢,产生很暗很黑的同心圈,圈与圈的距离很近,叫冬轮。因  相似文献   

5.
研究了东海产长木叶鲽的年龄与生长等生物学特性。样品取自1996 年4 月~1998 年11月,日本以西底拖网渔业在长崎鱼市场上岸的渔获物共2 584 尾。采用耳石进行年龄鉴定。体长与耳石径的关系,雌雄间有显著性差异。耳石上轮纹每年1~3 月份形成一次。周龄的推定体长,5+ 龄以上,雌性偏大  相似文献   

6.
鱼类的耳石信息分析及生活史重建——理论、方法与应用   总被引:1,自引:0,他引:1  
耳石(Otolith)是硬骨鱼类(Teleosts)在生长过程中沉积在内耳中的结石,主要矿物成分是CaCO3起声音接收和平衡定向作用。其内部轮纹(日轮Daily ring或年轮Annul ring)像在其他海洋动物特定钙化组织(如瓣鰓类外壳、珊瑚骨骼、多毛类颌骨、乌贼内壳、哺乳动物牙齿)中的轮纹一样随鱼类的发育而生长,并沉积着现场水环境中的主要化学元素。由于在形成过程中其轮纹形态结构与化学组成相当稳定,记录了鱼类个体生活过程中丰富的生物物理化学环境信息,所以,耳石信息分析可以揭示鱼类的生活史及其所经历的环境变化。在目前,耳石信息分析的应用涵盖了鱼类生态学研究的诸多方面,如鱼类的孵化和早期发育生长、产卵场和产卵期判定、仔鱼的运输过程(Larval transportation、年龄鉴定与种群鉴定(Age determination & population discrimination)、个体迁移(Migration)等。近年来,随着相关科学和技术的发展,它已经成为一种揭示鱼类生活史、生活史重建(Recastruction of life history)以及海洋环境域变(Regime shift)的关键技术,也是国际上渔业科学和海洋环境科学的研究热点。过去10年内三次国际鱼类耳石学术会议的成功举办(1993 Maryland-USA,Secor et al,1995a,1998- Bergen-Norway Fossum et al,2000;2004- Townsville Australia Begg et al,2005)大大推进了该研究领域的发展。其研究方向主要包括年龄鉴定与验证、显微结构分析(Microstructure)和微化学分析(Microchemistry)(Stevenson et al.,1992 ;Secor et al..1995a, Fossum et.al, 2000; Campana 1999, 2001; Elsdon et al, 2003a, b;Begg et al, 2005 )等。  相似文献   

7.
浙江近海大黄鱼 Pseudosciaena crocea( Richardson )的性成熟特性   总被引:2,自引:0,他引:2  
鱼类性成熟的开始是鱼类生命周期中转入繁衍后代的一个重要阶段。同一世代的个体开始性成熟的年龄、大小,以及延续期限与速度,是种和种内种群对水域生活条件的适应属性之一。 研究鱼类性成熟过程的特点,不仅在解决鱼类种群数量的预测与控制问题中,对补充过程的了解具有重大的意义,而且也为制订合理的渔业经营管理措施提供必要的生物学依据。 本文主要在于探讨浙江近海大黄鱼种群的性成熟特点及其影响因子;其次,讨论该特点在这一种群数量上的意义;并对捕捞规格(法定许可捕捞的鱼体大小和年龄等生物学指标)问题提出初步意见。 在这项工作中,单才根、滕文法和蓝志满等同志曾协助搜集资料、耳石制片和计算工作。在资料的收集中,得到洞头公社和温州地方水产部同的大力支持;本文承张孝威教授热情指导,井承成庆泰副教授等提出宝贵意见,均此谨表谢忱。  相似文献   

8.
荣成市海珍品育苗场与闽东水产研究所合作,成功地进行了大黄鱼南卵北移。日前,由闽东水产研究所进行大黄鱼亲鱼驯化产卵,然后空运到荣成市海珍品育苗场的首批受精卵,已成功培育出40万尾幼鱼,且发育良好。大黄鱼肉味鲜美、价格昂贵,具有适应能力强、生  相似文献   

9.
寿南小沙丁鱼鳞片表面结构及轮纹特征的扫描电镜观察   总被引:7,自引:0,他引:7  
运用扫描电镜技术对寿南小沙丁鱼鳞片形态结构及轮纹特征进行了观察。研究结果表明:寿南小沙丁鱼鳞片属圆鳞,与鲱形鳞相似。鳞片上有多少不一呈断裂状的辐射沟,环片呈山嵴状,与辐射沟基本平行,环片脊顶上有许多大小不同的卤状粒突。鳞片侧区的年轮和副轮清晰,在与年轮相交处,环片明显呈下凹弯曲,少数发生断裂。  相似文献   

10.
渤海黄盖鲽的年龄与生长   总被引:1,自引:0,他引:1  
孟田湘  任胜民 《海洋学报》1986,8(2):223-231
本文对渤海黄盖鲽的年龄与生长进行了探讨,材料取自于1982年4月—1983年5月渤海基础调查逐月的拖网渔获物。以耳石轮纹作为年龄鉴定的依据。耳石边缘宽、窄带出现频率和耳石边缘增长率I=R-rn/rn-rn-1的周年变化表明耳石轮纹的窄带主要形成于1—3月。分析了年轮形成与性成熟及水温的关系,求出黄盖鲽体重与体长的关系为:Wt=3.20×10-5Lt2.9048;耳石半径与体长的关系为:R=5.43×10-3+1.71×10-2L-1.20×10-5L2;其生长可用Von-Ber talanffy生长方程表示。Lt=L[1-e-k(t-t0)]Wt=W[1-e-k(t-t0)]2.9048其中L=418mm、W=1316g t0=-0.7475 k=0.252。拐点位置在t=3.48龄处。对生长速度、生长加速度、生长指标、相对增长率的计算反映了生长过程的变化。为了使逆算体长更符合理论值,计算了标准耳石半径和标准轮距,并据此逆算了各龄鱼的体长。  相似文献   

11.
In a study of the age and growth of Sillago aeolus, a total of 414 fish were collected from December 2000 to March 2002, around Okinawa Island. Ages of 403 specimens were determined by otoliths. Monthly changes in the percentage of otoliths with an opaque zone in the outer margin indicated that an opaque ring formed once a year, occurring between February and May. The rings can therefore be defined as annual rings. Ages of females were estimated to be 0+ to 4+, while those of males were 0+ to 2+. The von Bertalanffy growth curves were well fitted to age-standard length data of males and females, as follows: Male: Lt = 209.6 [1 − exp{−0.70 (t + 0.58)}]. Female: Lt = 297.7 [1 − exp{−0.42 (t + 0.61)}].  相似文献   

12.
The frequency of hyaline and opaque edges, back-calculation, and examination of otoliths bearing a natural tag were used to determine the time of ring formation for the pilchard off South West Africa. The extent of the error in the back-calculation method caused by seasonal variation in the relationship between otolith radius and fish length is assessed. The times at which hyaline rings were laid down between 1970 and 1981 are documented. Formation of hyaline rings is related to sea surface temperature (p < 0,001), prominent rings forming when the temperature is colder than the annual average. Generally, a prominent hyaline ring is formed in September and secondary rings in May and December.  相似文献   

13.
《Journal of Sea Research》2007,57(2-3):180-186
The main objective of this study was to develop a method to discriminate between wild and hatchery-produced Japanese flounder, Paralichthys olivaceus, based on variations in otolith macrostructure. Otoliths of wild flounder were more elliptical than those of hatchery-produced fish, whereas otolith area and marginal coarseness showed no clear differences. Otolith morphometry did not vary significantly with water temperature or feeding conditions in rearing experiments. Reduced ellipticity in the otoliths of hatchery-produced fish could be caused by biotic and abiotic conditions after release. Throughout the study, it was found that otoliths of Japanese flounder reared at 15 and 20 °C regimes showed opaque zones regardless of feeding condition, while otolith of fish reared at 25 °C had translucent zones. The potential of thermal marks and secondary zones as a new mass-marking system is presented.  相似文献   

14.
The present paper deals with the age and growth of P. yokohamae, whose specimens were collected monthly from April 1982 to May 1983 by trawl in the Bohai Sea. In the study the age and growth of P. yokohamae is determined by annual ring on otolith. On the basis of calculation of monthly changes in appearing frequency for opaque zones on the otolith edgs it is determined that the annual ring of P. yokohamae is formed in January-March every year.The relation of the standard length to the body weight is W=3.2×10-5L2.3018. The relationship between the otolith radius and the standard length is R=-5.43× 10-3 1.71 ×10-2L- 1.20× 10-5L2. The growth for this species is expressed by von-Bertalanffy equation, Lt = L∞[1-e-K(t-t0)], where L∞ = 418mm, t0 = -0.7475 and K=0.252.The P. yokohamae grows faster at the age of 1-2, but slower after two years old. The coordinate of weight-growth inflexion point is at t =3.84 and W=386 g.  相似文献   

15.
The clupeoid Etrumeus whiteheadi, known locally as the round herring, is an important component of the commercial purse-seine catch off South Africa. Three methods are employed to estimate the growth of juvenile round herring: examination of annual hyaline rings on fish otoliths, examination of daily growth increments on the otoliths, and analysis of length frequency distributions. The results show that fish smaller than 120 mm are less than one year old and that analysis of daily growth increments is unreliable for bigger fish. The problems of determining the age of fish on the basis of counts of the number of hyaline rings is also addressed by reference to a model which can be applied to any species with a protracted spawning period.  相似文献   

16.
Chum salmon (Oncorhynchus keta) in the North Pacific Ocean are anadromous fish, and spend most of their life in the sea until spawning in natal streams. To identify the stock and habitat characteristics of chum salmon, the composition of chemical elements (Ca, Mn, Sr, Zn, and Ba) in otolith was examined using laser ablation inductively coupled plasma mass spectrometry (LA-ICPMS). Two main types of analytical work have been carried out; discrete spot analysis and line scan analysis of otolith sections. Salmon otoliths were obtained from the eastern (Canada and USA) and western (Japan and Korea) North Pacific during 1997–1999 spawning seasons. Spot analysis of otolith cores demonstrated significant differences in the element concentration among countries (p = 0.003). Line scanning from the core to the margin showed that Sr concentrations were elevated at the core of the otoliths, decreased during the freshwater stage, increased suddenly at a certain point, and oscillated periodically towards the margin matching with year-ring. The elevated Sr concentration at the core may reflect the maternal contribution to the egg, and the oscillations toward the margin may reflect salinity gradients between onshore/offshore or north/south migrations. The Zn profiles also oscillated and corresponded to the annual ring of the otolith. However, the profiles of Sr and Zn oscillated oppositely after salmon migrated to saline water and the Zn uptake declined toward the rim of the otolith while Sr uptake increased.  相似文献   

17.
大黄鱼耳石、体长与年龄的关系   总被引:8,自引:0,他引:8  
运用1960年3月-1960年4月由中国科学院海洋研究所采集于洞头,吕泗渔场大黄鱼标本513尾,利用耳石切片确定大黄鱼的年龄,通过分析大黄鱼的耳石和体长的生长规律,证明大黄鱼的耳石生长不仅仅与鱼体生长成简单的直线相关,而且大黄鱼的耳石生长,体长生长和年龄三者之间密切相关,并推导出数学方程式,拟合计算结果表明,两各方程式能够较准确地表达三者之间的相关关系。  相似文献   

18.
The growth of hottentot is described by the relationship Lf (mm) = 538,015 (1?e?0,097(t + 0,431)). By determining the otolith growth rate and validating it with counts of daily rings identified on scanning electron micrographs of otolith sections, it was found that previous growth curves underestimated the age of the fish by one year. Differences in growth rate between sexes and over geographical regions were negligible. The ratio of males to females in sampled catches was 1:1,383 and 50-per-cent sexual maturity was attained at 220 mm fork length. There are two main spawning seasons, late autumn and summer, although some breeding activity continues throughout the year. Spatial differences in mean gonadosomatic indices were minimal.  相似文献   

19.
王可玲 《海洋科学》1987,11(1):52-53
本文以大连海洋渔业公司1953年以来的统计资料和其它资料为依据,分析论述了黄海牙鲆资源的历史和现状,以及牙鲆的分布与洄游,并提出了增殖黄海牙鲆资源的几条途径:1.进行人工放流以增殖资源;2.开展幼鱼放流;3.以增殖黄海北部渔场资源为主,兼顾全局;4.应充分重视牙鲆在鲽鲆类中恢复能力较强的特点,发掘其增殖潜力。  相似文献   

20.
The relationship between otolith radius and fish length in the pilchard Sardinops ocellata off South West Africa is shown to vary seasonally. This phenomenon may explain the sinuous nature of the relationships between body part and fish length in other studies. The seasonal variation is too large to be accounted for solely by ingrowth of the hyaline ring by opaque material. The otolith radius: fish length ratio shows a weak negative correlation with fish growth rate (r = ?0,7547, p = 0,1–0,05).  相似文献   

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