截线抽样法用于鄱阳湖江豚种群数量研究初报

运用截线抽样法调查了在春季 4月间鄱阳湖区长江江豚（Neophocaena phocaenoides asiaeorientalis）的种群密度和数量,得出该地区长江江豚种群密度估计值为 0．1940头／km²,估计数量为 388头。探讨了截线抽样法用于浅水型淡水湖泊调查的可行性和有效性以及要注意的问题。     

Diurnal changes of behavior and respiration of Yangtze finless porpoises (Neophocaena phocaenoides asiaeorientalis) in captivity

A preliminary study was carried out to investigate diurnal changes of behavior of three, one adult male, one adult female, and one juvenile female, Yangtze finless porpoises (Neophocaena phocaenoides asiaeorientalis) in captivity. The respiration and behavior of the porpoises were recorded for 222 hr across 42 days. Behavioral data were recorded for eight general categories: aerial display and fast swimming, begging for fish, playing, nonsexual socializing, sexual behavior, resting, rubbing, and miscellaneous (i.e., other behaviors not included in the above categories). Each behavioral category was scored using one‐zero sampling with 10‐min intervals. The adult male showed shorter mean respiratory intervals at night (19:00–7:00 h), whereas the mean respiratory intervals of the females were shorter during the day (7:00–19:00 h). Begging for fish of all individuals, playing of the juvenile female, nonsexual socializing, and miscellaneous behavior of the adult female and resting of the male were observed more easily in the day, and aerial display and fast swimming of the adults and resting of the females were observed more easily at night. No significant diurnal difference was found, however, in the remaining categories of each individual. Each of the three porpoises therefore showed a distinct diurnal pattern, but none was obviously more active in the daytime than during the nighttime. Results suggest that daytime‐only feeding schedules may be insufficient to meet the energetic needs of marine mammals that show a 24‐hr activity cycle, and that nighttime feeding may be a worthwhile addition to husbandry routines. Zoo Biol 0:1–11, 2005. © 2005 Wiley‐Liss, Inc.     

长江东流河道整治对长江江豚种群数量的影响

长江江豚是生活在长江中下游的濒危水生哺乳动物,通常活动在江心洲和浅水缓滩附近。航道整治改变了鱼类栖息活动的水文环境,也给豚类生存带来负面影响。本文根据长江东流河道整治施工前和施工后各3 次野外考察资料,分析了3 种流态中江豚的数量与群结构。结果表明,该工程实施前江豚主要栖息活动在边滩的分离区,其次在洲头的分流区。工程实施后,整治江段的江豚种群数量年下降率达8. 9% 。江豚在分流区活动已消失,在分离区集群规模较小,且在流态之间移动增大。本文研究结果也提示长江江豚就地保护难度越来越大,从长江干流中把长江江豚迁入故道中是一件刻不容缓的工作。     

长江江豚种群衰退机理研究进展

长江江豚（Neophocaena phocaenoides asiaeorientalis）是生活于我国长江中下游的一种独特的淡水小型鲸类,1996年被收录为IUCN濒危物种。在过去的三十年间,其种群数量呈快速下降趋势。数据显示,20世纪90年代以来,其种群下降速率约为每年6.3%。2006年考察发现长江干流中其种群数量少于1 200头,与15年前相比减少了50%以上。为了深入了解造成长江江豚种群快速衰退的机理,课题组从种群生态学、生物声学和种群遗传学三个方面开展研究工作。综述了该项目的研究进展,并对下一步的研究计划进行了展望。相关研究不仅能促进长江江豚保护生物学理论的发展,也有助于深化对白鱀豚衰退和灭绝过程的反思,并为其他长江水生生物资源的保护提供理论借鉴。     

人工饲养长江江豚的同性性行为和自慰行为

雌雄性之间的性行为对鲸类的生存和繁衍有着极其重要的意义。然而不具有繁殖功能的同性性行为和自慰行为在多种鲸类中存在。因此对鲸类非繁殖性性行为研究,将有助于深入认识该物种性行为特点和规律,并解决室内饲养可能存在的问题以及促进可控性人工繁殖的成功。本研究以人工饲养的7头长江江豚为研究对象,定义并描述了14种性行为。其中,同性之间的性行为定义为同性性行为,雌雄个体单独的性行为定义为自慰行为。雄性同性性行为发现于所有定义的性行为中,但雌性同性性行为仅在7种性行为中观察到。同性性行为（3633次）占总性行为（5563次）的65.31%,自慰行为（254次）占4.57%。同性性行为中,雄性之间的同性性行为（3438次,94.63%）远多于雌性同性性行为（195次,5.37%）。两头有父子关系的江豚（阿福和淘淘）之间的雄性同性性行为最多（1921次,55.88%）,雄性江豚之间的同性性行为可能存在结盟竞争关系或教育练习作用。两头青少年雌豚（F7和F9）之间的同性性行为最活跃（117次,60.00%）,雌性江豚之间的同性性行为很可能具有结伴交流的功能。     

定量评估豢养长江江豚个体间的优势关系

2000年1—4月和2000年4月—2002年4月,分别连续3个月和2年观察了中国科学院水生生物研究所白鱀豚馆6头长江江豚（3雌3雄,8个不同组合群）个体间发生的3种交互关系,即接近—逃开、接近—接触和接近—尾鳍击打。在累计8,162min的观察时间内,共观察到这些交互关系1,685次。本研究将江豚个体间发生的这3种交互关系作为个体间优势关系的指示,并分别给交互双方赋予不同的分值,采用优势比分矩阵方法定量分析了江豚个体之间的优势关系。结果表明江豚群体内存在优势关系。同性别个体之间,优势关系与年龄和饲养时间有关,年龄大的个体比年龄小的个体具有优势,饲养时间短的个体比饲养时间长的个体具有优势。但是,异性成年个体之间,优势关系通常是可变的。     

长江江豚种群生存力分析

长江江豚是一个独立的种群,由于人类活动的影响,其数量呈下降的趋势,运用漩涡模型（ＶＯＲＴＥＸ７．３）分析了长江江豚的种群生存力,预测了未来１００ａ长江江豚的种群动态,比较了在假设环境条件下以及采取和不采取保护措施长江江豚种群的濒危程度,并模拟了江豚饲养群体的动态,主要结果显示,长江江豚在未来１００ａ内灭绝的概率为０．０１平均灭绝时间为１００ａ,如长江环境状况进一步恶化,长江江豚的灭绝概率针大幅度提     

用微卫星指纹识别天鹅洲保护区长江江豚个体

DNA指纹个体识别技术是保护遗传学研究中的一种非常重要的手段。为了准确地识别天鹅洲保护区中的每一头长江江豚以开展保护遗传学及其它相关研究 ,并实施有效的种群管理 ,本研究应用 4个微卫星座位初步构建了该群体的DNA指纹图谱 ,并利用此图谱成功地对不同时期在保护区捕获的江豚进行了个体识别研究。结果显示微卫星指纹技术是一种适用于长江江豚个体识别研究的可靠手段     

长江安庆段江豚主要栖息地鱼类群落结构

长江皖河交汇处(皖河口)是安庆江段江豚主要的栖息地之一。为了解江豚主要栖息地鱼类群落结构,于2013年9月—2014年8月对皖河口及其附近4个断面逐月进行了鱼类调查。研究结果表明,共采集鱼类35种,与历史资料相比,鱼类物种多样性已经严重下降,并且小型化趋势明显。5个断面当中,皖河口鱼类种数最多,为27种,且以中上层鱼类餐和油餐为主要优势种;其余4个断面分别为16、20、19和14种,且多数断面以底层鱼类黄颡鱼和长须黄颡鱼为主要优势种。方差分析结果表明,皖河口渔获物的总数量和总重量与其他断面无显著差异,但总种数却显著高于断面1和5。对中上层、中下层和底层鱼类的进一步分析发现,5个断面的显著差异仅存在于中上层鱼类,且皖河口中上层渔获物的数量和重量均显著高于其他断面。由此推断,江豚选择皖河口作为主要栖息地可能主要由于其更加丰富的中上层鱼类资源。研究结果不仅有助于了解鱼类资源的变化,还对江豚的原地和迁地保护具有重要意义。     

长江和畅洲江段大型船舶的噪声特征及其对长江江豚的潜在影响

长江航运业的快速发展导致长江中船舶数量激增,相应的水体噪声污染可能对同水域的长江江豚（Neophocaena asiaeorientalis asiaeorientalis）产生一定的负面影响,本研究采用宽频录音设备对长江和畅洲北汊非正式通航江段的各类常见大型船舶（长>15m且宽>5m）的航行噪声进行了记录,并分析其峰值-峰值声压级强度（SPLp-p）和功率谱密度（PSD）等。结果表明,大型船舶的航行噪声能量分布频率范围较广（>100kHz）,但主要集中于中低频（<10kHz）部分,各频率（20Hz~144kHz）处的均方根声压级（SPLrms）对环境背景噪声在该频率处的噪声增量范围为3.7~66.5dB。接收到的1/3倍频程声压级（TOL）在各频率处都大于70dB,在8~140kHz频段内都高于长江江豚的听觉阈值。说明大型船舶的航行噪声可能会对长江江豚个体间的声通讯及听觉带来不利影响,如听觉掩盖。     

Seasonal changes in the local distribution of Yangtze finless porpoises related to fish presence

The Yangtze finless porpoise (Neophocaena asiaeorientalis asiaeorientalis) is an endangered freshwater porpoise subspecies unique to the Yangtze River basin. Seasonal variations in local distribution of the animal, as well as fish presence, sand dredging, ship navigation, and bridges were examined as potential factors affecting the occurrence of the animals. Passive acoustic surveys were performed regularly from May 2007 to August 2010, near the conjunction of the Yangtze River and Poyang Lake. The distribution of the porpoises was seasonally site‐specific. In May and August, the animals were detected more often at river junctions than in the lake, but vice versa from November to February. The rate of the porpoise detection was significantly higher in areas of fish presence than in areas of absence. The number of porpoises detected did not differ significantly between the sand dredging operation and the prohibition period (in 2008), although the number of vessels obviously declined in 2008. Ship traffic and bridges also did not appear to affect the presence of porpoises. These results showed the relative importance of the various environmental factors, which is important for conservation of not only Yangtze finless porpoise but also endangered isolated cetaceans.     

航道整治期间长江江豚临时庇护所建设及效果评估

航道整治期间为受扰动江豚提供临时庇护所,是在就地保护和迁地保护之外的一种尝试。2020年1月至2021年12月,在长江干线武汉至安庆段6 m水深航道整治过程中,选取马当圆水道建设长江江豚临时庇护所,通过禁止渔业捕捞,增殖放流和通航引导等措施来提升庇护所质量。监测结果表明,庇护所设立后其作为长江江豚栖息地的质量得到提高:夏季鱼类密度从(3361.2±1991.7)条/hm²上升到(12439.1±10734.5)条/hm²,冬季鱼类密度从(501.3±381.8)条/hm²上升至(1684.4±3770.9)条/hm²。通航船舶显著减少,水下噪声低于长江干流的平均水平。长江江豚临时庇护所建立后,枯水期庇护所水域内长江江豚的平均目击次数(4.3±0.6)、观察头次(6)和群体大小(1.4±0.5)都要显著高于庇护所建设前(P<0.05),丰水期则无显著性差异(P>0.05),说明庇护所在枯水期发挥了对长江江豚的保护作用。但长江江豚对庇护所的利用主要集中在进出水道两端,可能是枯水期部分水域过浅限制了江豚对庇护所的利用。分析认为,航道整治等涉水工程施工期间为江豚提供临时庇护所是一项可行措施,但要充分发挥庇护所对江豚的保护作用,必须全面考虑江豚对各项生态因子的需求,防止因关键因子带来的"木桶效应"制约庇护所的整体适合度。     

Respiratory pattern of captive Yangtze finless porpoises (Neophocaena phocaenoides asiaeorientalis)

Cetacean respiration usually happen in bouts. The most widely applied quantitative method used to analyze the structure of these bouts is the log_e-survivorship analysis, based on the assumption that the respiratory intervals are distributed as negative exponentials. However, for the data collected from three captive Yangtze finless porpoises (Neophocaena phocaenoides asiaeorientalis), we failed to obtain a convergent result with the application of log_e-survivorship analysis. However, the two-Gaussian model, which was recently proposed to analyze the feeding behavior of cows, was successfully fitted to the data. According to the fitting results, the overall respiratory pattern of the captive Yangtze finless porpoises can be described as a dive with a mean duration of around 30–40 s, followed by two or three ventilations with a mean interval of approximately 9 s. The average intra-bout intervals during both active and inactive periods are constant at 7.7–9.9 s for all individuals. However, when shifting from active to inactive states, the adult male and female decrease their mean numbers of respirations per bout and average length of inter-bout respiratory intervals, while the estimates of both parameters increase for the juvenile female. It was pointed out that the two-Gaussian model might be more adequate for cetacean respiratory-bout structure analyses than the log_e-survivorship technique.     

Genetic diversity and population demography of narrow‐ridged finless porpoises from South Korea on the basis of mitochondrial DNA variation: Implications for its conservation in East Asia

The narrow‐ridged finless porpoise, Neophocaena asiaeorientalis, is a small cetacean inhabiting the coastal waters of Taiwan, East China, Korea, and Japan, and is threatened by anthropogenic pressures. We analyzed the mitochondrial control region of N. asiaeorientalis from Korean waters to better understand the genetic diversity, population structure, and demographic history through comparison with previously reported sequences from Japan and China. The network and phylogenetic analyses illustrated that few common haplotypes were centrally located, and that most of the unique haplotypes were on the edges of the branches. Moreover, the estimates of fixation indices and gene flow revealed significant genetic differentiation among the regions in East Asia. The mismatch distribution suggested a population expansion in the late Pleistocene. We propose that the current genetic variation in N. asiaeorientalis in East Asia was shaped by historical demographic expansion during the late Pleistocene. The N. asiaeorientalis of Korean waters has the highest diversity observed with the sampling available at this time. However, the abundance of N. asiaeorientalis in Korean waters has rapidly declined and the species needs protection from bycatch.     

长江江豚对八里江江段的利用及其栖息地现状的初步评价

通过定点和流动观察的方法，作者使用行为指数和栖息地利用指数定量分析了长江江豚（Neophocaena phocaenoides asiaeorientalis))于1996—2000年间对八里江江段的利用和选择状况。结果表明：江豚在八里江江段的行为指数大小顺序为摄食＞抚幼＞玩耍＞休息，摄食和抚幼是江豚在八里江江段的优势行为；江豚栖息于离岸距离100—300m的近岸带占81．8％，栖息于水深小于9m的水区占73．3％；江豚分布密度随水深增加而逐步递减(典型的指数分布)；江豚活动水区的流速范围是0．3-1．2m／s，透明度范围是0．2—0．8m，江豚在八里江江段对水体流速和透明度没有明显的选择性；栖息地利用指数高的断面一般是饵料鱼类聚集、2—4股水流的交汇处。八里江江段的众多异质小生境为江豚提供了充足饵料和繁育抚幼的适宜场所；同时八里江江段为江豚提供了庇护、休息和玩耍的足够活动空间。八里江江段成为长江干流适宜江豚活动的最佳栖息地之一，也是常年江豚在此大规模集聚的理想江段之一[动物学报49(2)：163—170，2003]。     

长江安庆段航道整治对长江江豚数量和分布的时空影响

栖息地丧失和破碎化是威胁长江江豚(Neophocaena asiaeorientalis)种群长期发展的主要因素之一。航道整治工程是导致江豚栖息地丧失和破碎化的一个主要原因,研究工程施工和运行对江豚数量和分布的影响可为江豚栖息地管护提供有益信息。通过对湖口-吉阳矶水域江豚数量和分布的持续调查,分析了安庆段航道整治工程施工和运行对江豚的影响。12次目视调查共在研究水域发现江豚258群次613头次,工程施工前、施工期和初步运行期单次考察分别平均观察到江豚(67.0±24.3)头次、(35.6±22.2)头次和(50.0±2.8)头次。在主要施工区共发现江豚79群次185头次,施工前、施工期和初步运行期单次考察分别平均观察到江豚(18.60±12.03)头次、(10.4±7.3)头次和(20.0±4.2)头次。工程不同时期主要施工区江豚的数量及占比在统计学上没有显著差异。主要施工区S2和S3工程段施工期江豚平均分布密度((0.18±0.17)头/km、(0.04±0.08)头/km)较施工前((0.62±0.16)头/km、(0.40±0.29)头/km)显著下降,S5和S6工程段施工期平均...     

Population Genetic Structure of the Yangtze Finless Porpoise (Neophocaena phocaenoides asiaeorientalis): Implications for Management and Conservation

Understanding the population genetic structure is a prerequisite for conservation of a species. The degree of genetic variability characteristic of the mitochondrial DNA control region has been widely exploited in studies of population genetic structure and can be useful in identifying meaningful population subdivisions. To estimate the genetic profile of the Yangtze finless porpoise (Neophocaena phocaenoides asiaeorientalis), an endangered freshwater population endemic to China, the complete mtDNA control region was examined in 39 individuals belonging to seven different stocks inhabiting the middle and lower reaches of the Yangtze River. Very low genetic diversity was found (nucleotide diversity 0.0011± 0.0002 and haplotypic diversity 0.65± 0.05). The mtDNA genetic pattern of the Yangtze population appears to indicate a founder event in its evolutionary history and to support the marine origin for this population. Analyses by F_st and Φ_st yielded statistically significant population genetic structure (F_st = 0.44, P < 0.05; Φ_st = 0.36, P < 0.05). These results may have significant implications for the management and conservation of the Yangtze finless porpoise in the future.     

B-Mode ultrasonographic evaluation of the testis in relation to serum testosterone concentration in male Yangtze finless porpoise (Neophocaena phocaenoides asiaeorientalis) during the breeding season

The use of ultrasonography as a noninvasive tool for assessing the reproductive status of the male Yangtze finless porpoise (YFP; Neophocaena phocaenoides asiaeorientalis) was validated by correlating ultrasonographically determined testicular volume (TV) and testicular parenchyma pixel intensity (PI) with serum testosterone (T) concentration. The testes of 13 free-ranging male YFPs from the Tian-e-Zhou Reserve and three captive animals from the Baiji Dolphinarium (Wuhan, China) were examined ultrasonographically during April 2008. Testis volume was determined using Lambert's formula for an ellipsoid. Testicular parenchyma PI was evaluated by analyzing testicular ultrasonograms using pixel analysis software (Image J). Serum T concentrations were determined using a single-antibody radioimmunoassay. The TV, PI, and serum T concentration were low and similar in animals with body length <133 cm, highest in those with body length ≥142 cm, and highly variable in those with body length from 133 to 141 cm. Both TV and PI were closely correlated with serum T concentration (r = 0.91 and r = 0.85, respectively; P < 0.01), indicating a consistent association between structural and functional development of the testis. In conclusion, we inferred that puberty onset in male YFPs occurred when TV was >150 cm³ and PI was >60 during the breeding season and that testicular ultrasonography and pixel analysis was an efficient, noninvasive, real-time tool to evaluate testicular function of live male YFPs.     

长江江豚对人工投食适应过程的观察

作者于1989,1992,2001 和2003 年,从长江铜陵江段共捕获24 头长江江豚,在长江干流水域中,用不同的围养方式做摄食行为的观察,累计88 d。结果表明,野外捕获的长江江豚对人工投喂有3 种适应行为:(1)拒食行为;(2)警戒行为;(3)摄食行为。长江江豚的平均拒食天数为2.4 d,其中成年江豚拒食达3 d,而未成年江豚仅拒食1.5 d,两者差异极为显著(P < 0.01)。在冬季和春季圈养试验中,长江江豚的日食量随时间呈上升趋势,冬春季差异显著(P <0.01)。第2 周后江豚警戒行为所用时间不足3 min,但持续时间较长。根据冬季观察,7 周后长江江豚在40 min 内所摄取的食量不足体重的7% ,推测其摄食行为仍处在适应调整阶段。     

Development and characterization of polymorphic microsatellite loci in the endangered Yangtze finless porpoise (Neophocaena phocaenoides asiaeorientalis)

The finless porpoise (Neophocaena phocaenoides) is one of the smallest cetacean species widely distributed in the shallow coastal waters of the Indo-Pacific Oceans. The population size of the Yangtze subspecies (N. p. asiaeorientalis) has sharply decreased in the last two decades and access to objective data on its population structure and genetic diversity would be of great assistance for their proper management. Here we report on the isolation of nine polymorphic microsatellite using the “Fast Isolation by AFLP of Sequences Containing repeats” (FIASCO) protocol. Polymorphism was assessed using 30 porpoise individuals randomly sampled in the Yangtze River. The number of alleles per locus varies from 2 to 9, with an average value of 5.56, whereas the ranges of observed and expected heterozygosities were 0.300–0.633 (mean 0.496) and 0.473–0.804 (mean 0.659), respectively.