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1.
对2007-2018年辽宁海域发现的39头死亡东亚江豚(Neophocaena asiaeorientalis sunameri)进行了外部形态参数测量和生长规律分析,并通过观察牙齿中的生长层组对2014-2018年的27头江豚个体进行了年龄鉴定.结果表明:死亡江豚以0~4龄个体为主,雄性21头,雌性18头;同龄雌雄个体间的体长、体重均无显著差异(P>0.05);所有江豚样本的体重与年龄(Y=137e^-2.475exp(-0.205t))、体长与年龄(Y=232(1-0.680e^-0.161t)均极显著相关(P<0.01),且随年龄增大,体重、体长均增加但增速下降.死亡江豚的发现时间在不同的海域存在差异:黄海北部海域集中在每年的3-6月,以大连星海湾至老虎滩沿岸为多;渤海的辽东湾海域主要在每年的10-11月初,多发现在大连长兴岛以北的海域.辽东湾海域江豚的死亡多发生在渔业作业期,可能与渔业生产活动有关.研究还发现,在一年中辽东湾海域死亡江豚集中出现的时间与斑海豹的分布期存在交替现象,是否与两种海洋哺乳动物适应海水温度能力、种群间的食物竞争以及季节性迁移等因素有关还有待于进一步的研究.  相似文献   

2.
中国沿岸漫游的环海豹及其他鳍脚类   总被引:1,自引:1,他引:0  
鳍脚类主要分布在寒冷水域。我国海域的水温相对较高,已发现的鳍脚类种类和数量都很少,除黄海和渤海的斑海豹外,其他都是离开了正常分布区的漫游个体。对斑海豹Phoca largha已有过几篇报道(汪克贤,1955;李秀朋,1965;李荣光,1980;王者茂,1984)。对另3种鳍脚类只有零星记录(王者茂,1973;诸葛阳,1982;黄圮,1984)。本文首次报道漫游到中国近海的环海豹 Phoca hispida ochotensis Pallas,同时对中国沿岸斑海豹及另3种鳍脚类的漫游个体作简要介绍。  相似文献   

3.
草鱼仔鱼耳石的自然标记和生长轮的清晰度   总被引:4,自引:0,他引:4  
将野生和人工繁殖的草鱼仔鱼的耳石取出并置于显微镜下观察微结构特征。结果表明 :草鱼耳石一般有一个圆形或卵圆形的原基和中心核 ,但有 0 4 1%~ 4 6 7%的样本具有双原基或双中心核。343尾野生仔鱼中 ,6 71%的个体在矢耳石和微耳石上具有营养转换标记 ,而 187尾人工繁殖的仔鱼中 ,在矢耳石和微耳石上出现营养转换标记的比例分别是 6 4 17%和 5 0 80 % ;在营养转换标记处 ,矢耳石和微耳石的直径分别为 5 4 12±9 4 9μm和 4 0 4 8± 7 0 2 μm (n =5 0 ) ;133尾野生仔鱼在转入实验室饲养的过程中 ,86 4 7%的个体在耳石上形成了转移标记 ;野生仔鱼生长轮纹清晰的矢耳石 (n =5 2 1)和微耳石 (n =5 2 1)样本的比例分别低于 10 %和2 5 % ,但在人工饲养仔鱼中 ,95 0 0 %个体的矢耳石 (n =186 )和 88 0 0 %个体的微耳石 (n =184 )具有清晰的生长轮纹 ;野生仔鱼经人工饲养后 ,其耳石上在饲养期间沉积的生长轮的清晰度亦明显比在野外生存期间沉积的高 ;对比实验显示饥饿对仔鱼耳石生长轮的清晰度没有明显的影响.  相似文献   

4.
为了证实草地螟Loxostege sticticalis L.(鳞翅目: 螟蛾科)由我国华北越冬区向东北迁飞危害的假说并提供直接的证据, 采用网捕成虫喷雾染料标记释放回收的方法,于2009年越冬代草地螟成虫盛发期间(6月1-4日)分别在内蒙古武川县(41.07°N, 111.42°E)和察右中旗(41.13°N, 112.58°E)的6个标放点共标记当地越冬代草地螟成虫约181万头并自然释放。标记释放后, 在东北、 西北和华北11个草地螟常发省(市、 区)组织各级监测预警部门利用虫情测报灯、 捕虫网和性诱剂诱捕器等多种器械进行回收, 先后于2009年6月7-29日在内蒙古科右中旗、 乌兰浩特、 扎兰屯分别回收到由察右中旗标记释放的成虫9头, 在辽宁省北票市回收到由武川县标记释放的成虫1头。标记释放点至回收点直线距离为725~1 117 km。这是迄今为止世界上确认的草地螟最远迁飞距离。这些证据不仅证实了我国越冬代草地螟成虫能从华北迁往东北危害, 而且为进一步了解草地螟的种群动态规律, 改善草地螟的预测预报技术提供了重要的科学依据。  相似文献   

5.
《生物学通报》2006,41(3):26-26
据四川卧龙中国保护大熊猫研究中心透露,经过近3年的培训后,我国第1只接受野化训练的人工繁殖大熊猫“祥祥”真的变野了,这标志着我国人工繁殖的大熊猫第1次具备了野外生存的能力,我国首例人工繁殖大熊猫野外培训实验获得成功。  相似文献   

6.
2007年4-10月,采用野外和室内实验相结合的方法,研究了荒漠草原马粪中的粪金龟子群落组成和对马粪分解的影响.共捕获粪金龟子13528头,隶属于3科4属26种,优势种为符号蜉金龟(Aphodius comma),占总捕获量的88.5%,不同季节粪金龟子群落组成明显不同;在鲜马粪中活动的粪金龟子以粪居型蜉金龟为主,在鲜马粪堆置3d时种数和个体数达到最高,6d后全部离开;马粪经过136 d分解,残留率为52.5%,残留粪样中氮和磷释放较慢,钾释放较快;结合室内分解实验的结果,认为粪金龟子主要通过在马粪中活动对其分解产生影响,并与风蚀作用成为荒漠草原马粪块破碎的重要动因,主要发生在春季和秋季.  相似文献   

7.
雕鸮是夜行性猛禽,主要捕食鼠类,对农业发展和生态保护有重要作用。为了解雕鸮及其他猛禽在放飞后的活动轨迹,实现救助的最终目标,对3只放飞的雕鸮进行无线电追踪,以评估经过救助的雕鸮在野外的生存能力与活动情况。采用最小凸多边形法分别计算其活动区(home range)大小,并结合追踪记录对雕鸮选择的生境进行分析,发现该3只雕鸮,无论是有野外存活经验的成鸟还是缺乏野外存活经验的幼鸟,在经过救助、放飞后都能适应野外环境存活下来,且偏好于选择湿地和林地。  相似文献   

8.
西藏墨脱发现灰头钩嘴鹛   总被引:3,自引:2,他引:1  
林植  何芬奇 《动物学杂志》2016,51(2):336-336
正2015年10月20日08:46和09:33时,于西藏林芝市墨脱县巴日村仁青崩附近(29°20′N,95°21′E)海拔1 380 m及1 450 m处以SWAROVSKI 8.5×42双筒望远镜分别观察记录到有钩嘴鹛个体(2只)和小群体(4只)在灌丛间活动觅食并拍摄到照片,其羽色明显有别于当地所曾记录到的数种钩嘴鹛,经查阅相关野外手册(约翰·马敬能等2000,Robson 2005,Collar et al.2007,Grimmett et al.2011),认定为灰头钩嘴鹛(Pomatorhinus schisticeps)。  相似文献   

9.
2013—2014年,河南董寨国家级自然保护区分别对野化训练的60只朱鹮进行放飞。采用卫星定位、无线电遥测和持续跟踪法对释放后的朱鹮进行监测。共监测到释放的朱鹮个体23只,活动面积约320 hm~2,最远扩散距离为(16.5±3.2)km,并形成了较为集中的6个不同数量活动及夜宿群体。发现3~5岁朱鹮野外存活比例较高,占放飞数量42.3%,雌鸟存活情况高于雄鸟。2014年、2015年分别有1对和6对朱鹮在野外繁殖,共产卵21枚,受精卵17枚,受精率为80.9%,出雏17只,成活出飞幼鸟15只,出飞率达88.2%。表明经过野化训练的朱鹮在大别山地区可以生存且繁殖成功。  相似文献   

10.
陈鹏  叶辉  母其爱 《生态学报》2007,27(6):2468-2476
2005年7月在云南怒江流域地区,以荧光粉作为标记物,采用“标记-释放-回收”方法,对怒江流域桔小实蝇迁移扩散规律进行了研究。以释放点潞江坝为中心,东南西北4个方位设立桔小实蝇回收点,经过7d的回捕,从释放点沿潞江以北至六库沿线共回收到的标记桔小实蝇43头,最远在距释放点以北97km的地方回收到标记桔小实蝇5头。沿怒江在释放点以南,仅在小于29km的范围内回收到标记桔小实蝇17头。释放点东面和西面未能回收到标记桔小实蝇。分析释放点以北各回收点标记桔小实蝇与非标记桔小实蝇的相互关系揭示,非标记桔小实蝇与标记桔小实蝇在空间动态中具有相同的行为模式,由此推论非标记桔小实蝇与标记桔小实蝇可能来自同一种群。分析怒江流域区的自然地理发现,潞江坝桔小实蝇可借助怒江两边高大山脉形成的天然河谷通道,在适宜的气候条件下,在北上气流的携带下,实现由南向北的远距离迁移扩散;同时,由于高大山脉的阻隔,使潞江坝桔小实蝇没能向东西两个方向作远距离扩散迁移。研究首次揭示了在特定峡谷地区桔小实蝇扩散迁移现象,为桔小实蝇迁移扩散研究提供了新鲜实例,为在当地制定切实有效的桔小实蝇防治策略提供了基础信息。  相似文献   

11.
Population genetic structure of the spotted seal, Phoca largha, along coastal regions of Hokkaido was investigated, using mitochondrial DNA (mtDNA) sequences. A 571-bp fragment of the mtDNA control region and adjacent threonine and proline transfer RNA genes was sequenced from 66 seals. We categorized all individuals into three groups considering sampling area and season: twenty-four seals from the Sea of Okhotsk in winter, 11 seals from the Sea of Okhotsk coast in fall, and 31 seals from the Sea of Japan coast in winter. From the 66 animals, 57 haplotypes were identified. Compared with the harbor seal sequence, all spotted seals examined shared two deletions in the control region, which distinguished between the two species. Forty-nine haplotypes were represented by a single individual, and haplotypes shared by more than two animals were generally restricted to same sampling-groups. Phylogenetic trees did not indicate clear geographic differences among the three groups. An Analysis of molecular variances (AMOVA) did not showed any significant population genetic structure in Hokkaido spotted seals (Phi(st )= -0.003). Our results showed a high level of diversity but no genetic structure, and did not deny the possibility that seals in the Okhotsk breeding concentration mainly stayed in the fall Okhotsk and also inhabited in the winter Sea of Japan.  相似文献   

12.
We monitored movements and haul-out patterns of four ringed seals Phoca hispida , off Northwest Greenland between 5 June and 31 October 1988 using the Argos Data Collection and Location System When the seals were hauled out on fast ice their locations were accurately determined, but when they were at sea, few accurate locations were obtained, evidently because these seals spent little time at the surface between dives The seals remained within the fjord where they were tagged, and hauled out often to early July Thereafter, as fast-ice disappeared, they dispersed widely and spent less time hauled out Time of day had no significant effect on haul-out patterns Haul-out periods declined significantly from June to August and increased in September-October Satellite contact with one seal was lost after 16 d while the seal was still in the fjord in late June One seal travelled over 200 km southwest and was located 4 July in offshore waters of Smith Sound 30 d after instrumentation Another seal moved southeast along the Greenland coast where contact was lost after 49 d on 23 July The fourth seal moved north along the Greenland coast, hauled out regularly on ice, and returned south along the coast in late September and October after 181 d of contact with the satellite  相似文献   

13.
The distribution and abundance of spotted seals (Phoca largha) and ribbon seals (Phoca fasciata) were assessed in March and April, 2000, by aerial line-transect surveys along the southern edge of the pack ice off the coast of Hokkaido (southern Sea of Okhotsk), Japan. Five hundred and seventeen spotted seals and 107 ribbon seals were found on the total 2944 km survey line. Total abundance was estimated to be 13 653 spotted (95% CI = 6167–30 252) and 2260 ribbon seals (95% CI = 783–6607) in March, and 6545 spotted (95% CI = 3284–815 644) and 3134 ribbon seals (95% CI = 1247–17 802 512) in April. The pack ice area off Hokkaido had higher densities (0.54 seals km–2 and 0.58 seals km–2 in March and April, respectively) of spotted seals than those reported in eastern Sakhalin, whereas densities (0.09 seals km–2 in March and 0.28 seals km–2 in April) of ribbon seals were lower than those in eastern Sakhalin. The large number of spotted seal pups suggests that the study area is an important breeding center. A greater number of female spotted seals with pups tended to be found in the center of larger and rougher floes than in other categories, and they were more abundant in stable pack ice areas. Observations of ribbon seals were limited because the survey period preceded the peak of pupping season. Ribbon seal surveys were also hampered by the inability to fly over the main breeding area between the Shiretoko Peninsula and Kunashiri Island.  相似文献   

14.
Satellite-linked tags were attached to 12 spotted seals (Phoca largha) captured at a coastal lagoon in the eastern Chukchi Sea during August 1991–1993. Movements of seals were tracked for 32–298 days using the Argos system. Of 9,651 total location records obtained, 7,268 were usable. Individual seals were located on 41–96% of the days that tags were operational. During August–November, tagged seals alternated haul-outs at coastal sites lasting 1–304 h with trips to sea of 14–901 h. Coastal haul-outs occurred at 14 sites in western Alaska and eastern Russia. On several trips to sea, seals covered distances of more than 1,000 km. Movement southward from the Chukchi Sea generally began in October, with most of the seals passing through the Bering Strait during November. Seals first hauled out on sea ice in October (Chukchi Sea) or November (Bering Sea), and generally moved southward during October–December as sea-ice coverage increased. Seven seals, whose transmitters were still operating, spent December to June in the Bering Sea region between Kuskokwim Bay and Anadyr Gulf, which corresponded to the location of the ice front. The seals made active east-west movements within the ice front. Spotted seals are unlike other ice-breeding seals in that they regularly use coastal haul-outs during summer and autumn. Compared to the closely related Pacific harbor seal (Phoca vitulina richardsi), spotted seals make much longer trips to sea and spend longer continuous periods at their haul-outs during summer and autumn. Received: 9 April 1997 / Accepted: 30 September 1997  相似文献   

15.
受伤和体弱白鹤的救护及放归是白鹤保护的重要方式之一。2014—2016年间,先后对8只救护白鹤和2只野生白鹤进行环志并安装卫星跟踪器,根据所获得的卫星跟踪数据来分析比较救护白鹤与野生白鹤在秋季迁徙路线和在重要中途停歇地的最大日活动距离、活动区分布和面积、生境类型等方面的异同。结果显示,救护白鹤放归当年与放归次年以及救护白鹤放归当年与野生白鹤的秋季迁徙路线和活动规律之间存在明显差异,但救护白鹤放归次年与野生白鹤之间差异不明显。(1)放归当年,4只救护白鹤在农田和水塘停歇1个月左右,停歇时长明显高于野生白鹤和放归次年的救护白鹤。(2)救护白鹤放归当年在跨海方式、登陆地点、停歇地点以及登陆后的迁徙方向上表现出多样性和不确定性,其中部分个体在迁徙过程中有停顿徘徊、迷失迁徙方向的现象,且跨越渤海和大别山的距离大于放归次年的救护白鹤和野生白鹤。(3)救护白鹤放归后4天内每日最大活动距离小,而后高低分化明显,无明显规律,而救护白鹤放归次年的每日最大活动距离规律变化与野生白鹤较一致。(4)与救护白鹤放归次年以及野生白鹤的活动规律相比,救护白鹤放归当年的栖息地位点变化频繁,具体表现为生境类型选择的多样化,且无明显规律,同时活动区面积较小。探索救护白鹤放归野外后与野生白鹤迁徙路线和活动规律的差异,对救护白鹤的科学放归具有指导意义。  相似文献   

16.
Adélie penguins (Pygoscelis adeliae), after breeding in Antarctica during the austral summer, undergo a winter migration before returning to the breeding grounds 8 months later. It is the major source of adult mortality, with about a quarter of them not returning. Here we describe the first attempt to track the winter migration of Adélie penguins using satellite telemetry. Transmitters were attached to two penguins on 16 February 1991 after their post-breeding moult at Cape Bird, Ross Island, Antarctica. Transmissions were received from one penguin (bird #1) for 4.4 months, during which time it travelled 2792.6 km from the rookery (nearly 1500 km straight-line distance). Transmissions were received from the other penguin (bird #2) for 2.5 months during which time it followed a path remarkably similar to that of bird #1. The penguins travelled northwards up the coast of Victoria Land, keeping within 100 km of the coast, rounding Cape Adare soon after 29 March and were midway between the Balleny Islands and the Antarctic coast on 3 May. Thereafter, the record from bird #1 shows that it travelled further westwards until, when opposite the Mastusevich Glacier Tongue of the Mastusevich Glacier, it turned due north and moved away from the coast. By 29 June, when transmissions ended, its progression had slowed and it was northwest of the Balleny Islands near a zone where pack ice covered 75% of the surface of the sea. Two novel points that arise from this study are: (1) that Adélie penguins from Cape Bird undergo winter migrations of not less than 5000 km, and (2) that they may be travelling to common overwinter feeding grounds.  相似文献   

17.
Concentrations of chlorinated hydrocarbons and their derivatives in the organs of spotted seals captured in the Sea of Japan are determined. Isomers of hexachlorocyclohexane (HCCH) and metabolites of dichlorodiphenyltrihlormetilmetan (DDT) are detected in all the studied animals in all the samples, but the highest concentrations are found in adipose tissue, which is a peculiar depot in which toxins are accumulated. Substantial differences in the extent of damage by toxins are discovered in seals of different populations, which is due to different intensities in the action of technogenic load on separate water areas. The level of accumulation of lipophilic xenobiotics in the tissues and organs of spotted seals of the Sea of Japan, particularly from the Peter the Great Bay (PGB), turn out to be very high (several orders of magnitude higher than that in spotted seals from the Tatar Strait and the coastal region of Hokkaido). Such a high level of chlorinated organic pesticides (COPs) has not yet been detected in any Pinnipeds inhabiting the northern part of the Pacific Ocean. The results of our studies allow us to state that COPs have been present in the ecosystem are the Sea of Japan for a long time and have undergone substantial transformation.  相似文献   

18.
Habitat partitioning by adult and subadult ringed seals (Phoca hispida) is poorly understood. Conclusions about displacement of subadult seals to suboptimal offshore habitat are largely based on nearshore observations as few satellite tagging studies include data from winter months. In this study, movement patterns of 14 subadult and 11 adult ringed seals were monitored in the Bering and Chukchi seas using satellite-linked telemetry. Seals were captured in Kotzebue Sound, Alaska, during October 2007 and 2008 and tracked for 17–297 days. Subadult ringed seals traveled south from the Chukchi Sea into the Bering Sea ([`(x)] \bar{x}  = 36 km/day) as sea ice coverage increased during November and December, remained ~1,000 km south near the ice edge during winter and returned north in the spring with the receding ice edge. Adults remained in the Chukchi and northern Bering seas, where their movements were more localized ([`(x)] \bar{x}  = 22 km/day). Adults were on average 322 km farther from the ice edge and 48 km closer to land and shorefast ice than were subadults. During winter, adult ringed seals construct and maintain breathing holes through the ice, and in spring, females give birth in subnivean lairs, mostly in shorefast ice; adult males defend breeding territories around those lairs. Our results show that subadult ringed seals, unconstrained by the need to maintain territories that contain stable breeding/pupping habitat, moved south to the Bering Sea ice edge, where there are better feeding opportunities, lower energetic costs (no breathing hole maintenance), and less exposure to predation.  相似文献   

19.
The composition, distribution and seasonal variation of the benthic marine algae in the northern Bohai Sea coast were studied. 119 species of benthic marine algae were found in the northern Bohai Sea coast. They belong respectively to Cyanophyta, Thodophyta, Phaeophyta and Chlorophyta. The study showed that the marine algae flora of the northern Bohai Sea coast belongs to warm temperate in nature with considerable subtropical composition. There were 57 species of economic algae in the northern Bohai Sea coast and 7 newly recorded species.  相似文献   

20.
渤海北部底栖海藻的初步研究   总被引:11,自引:0,他引:11  
报道了渤海北部底栖海藻的种类组成、区系性质、群落结构和季节性变化。经调查,该海区隶属于蓝藻门、红藻门、褐藻门和绿藻门的底栖海藻共有119 种,其中包括57 种经济海藻和7 个新记录种。研究表明,渤海北部底栖海藻的温度性质以暖温带性为主,带有一定的亚热带性;其群落成分的季节性变化非常明显  相似文献   

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