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1.
Environmental cues that are associated with individual movement of threatened Gulf Sturgeon from upriver areas to nearshore and offshore winter feeding areas have been described throughout much of their range in the Gulf of Mexico. In this study, we focus on small‐scale movement of Gulf Sturgeon between summer ‘holding’ areas and the fall staging area in the Pascagoula River system (Mississippi, USA). We evaluated a set of logistic regression models using Akaike's Information Criterion and found that relative changes in barometric pressure, time of day, and water temperature were cues for small‐scale Gulf Sturgeon movements during fall outmigration. Numerous environmental cues appear to drive the activity of Gulf Sturgeon in staging areas, indicating the complexity of abiotic factors affecting the observed staging patterns during emigration. The identification of the environmental drivers that are associated with Gulf Sturgeon movement is particularly important if these known saline transition zones change spatially annually with variable rainfall or due to water withdrawals and are used by Gulf Sturgeon making osmotic adjustments while moving downriver.  相似文献   

2.
Artificial rearing of fry has been introduced as an alternative to supply fry and juvenile sturgeon in order to restock the depleted sturgeon population in the Caspian Sea. The aim of this study is to assess the feed selection characteristics of sturgeon (Acipenser persicus) fry during the period in which they stay in earthen ponds before being released into the river. Sturgeon fry weighing around 150 mg were introduced into five almost similar‐sized earthen ponds. The ponds were enriched with fertilizer to supply natural food for the fries. A weekly sample of six specimens was collected from each pond during the 5 weeks of the experiment. All collected fish were weighed and then dissected for inspection of the stomach and the intestine content. The overall stomach content measured from 150 fish showed that around 74% of the stomach content was composed of chironomids and the rest was daphnia and cyclops. At the beginning of the study (first 2 weeks), sturgeon fry feed more on daphnia and cyclops; this trend, however, reversed in the last 2 weeks of the study. In conclusion, sturgeon fry feed on three prey groups—chironomids, daphnia and cyclops—during their lifespan in earthen pond. Feeding on chironomids larvae increased with sturgeon fry size.  相似文献   

3.
鲟鱼病原性疾病研究进展   总被引：1，自引：0，他引：1  
鲟是地球上最古老的物种之一。我国自1991年后开始鲟类的商业化养殖,主要品种有引进的匙吻鲟、杂交鲟、小体鲟、俄罗斯鲟和西伯利亚鲟,黑龙江流域出产的施氏鲟、达乌尔鳇,以及施氏鲟和达乌尔鳇的杂交种等。随着养殖业的发展,鲟疾病不断增多,严重制约了养殖产业的健康发展。目前发现的鲟致病性病原有病毒、细菌、真菌和寄生虫等。概述了目前国内外鲟病原性疾病的研究进展,包括感染种群、致死率、临床症状、病原分离鉴定和药物控制等方面。目前对鲟病害的研究,在发病机制、免疫防治以及结合环境和营养因素的综合防控技术等方面还十分缺乏,应系统开展鲟疾病的流行病学、病原学、诊断技术以及防控技术研究。  相似文献   

4.
Abstract – In 1997 and 1998, sampling was conducted on the Missouri and Yellowstone rivers, North Dakota, to obtain information on the distribution, abundance, and habitat use of the flathead chub (Platygobio gracilis Richardson), sicklefin chub (Macrhybopsis meeki Jordan & Evermann), sturgeon chub (Macrhybopsis gelida Girard), and western silvery minnow (Hybognathus argyritis Girard), four declining fish species (family Cyprinidae) native to the Missouri River basin, USA. The study area consisted of four distinct river segments near the confluence of the Missouri and Yellowstone rivers – three moderately altered segments that were influenced by a main‐stem dam and one quasi‐natural segment. One moderately altered segment was located at the confluence of the two rivers (mixing‐zone segment (MZS)). The other two moderately altered segments were in the Missouri River adjacent to the MZS and extended up‐river (above‐confluence segment (ACS)) and down‐river (below‐confluence segment (BCS)) from this segment. The quasi‐natural segment (Yellowstone River segment (YRS)) extended up‐river from the MZS in the Yellowstone River. Catch rates with the trawl for sicklefin chub and sturgeon chub and catch rates with the bag seine for flathead chub and western silvery minnow were highest in the BCS and YRS. Most sicklefin and sturgeon chubs were captured in the deep, high‐velocity main channel habitat with the trawl (sicklefin chub, 97%; sturgeon chub, 85%), whereas most flathead chub and western silvery minnow were captured in the shallow, low‐velocity channel border habitat with the bag seine (flathead chub, 99%; western silvery minnow, 98%). Best‐fit regression models correctly predicted the presence or absence of sicklefin chub, flathead chub, and western silvery minnow more than 80% of the time. Sturgeon chub presence and absence were predicted correctly 55% of the time. Best‐fit regression models fit to fish number data for flathead chub, sicklefin chub, and sturgeon chub and fish catch‐per‐unit‐effort (CPUE) data for flathead chub also provided good fits, with R2 values ranging from 0.32 to 0.55 (P < 0.0001). The higher density and catch of the four native minnows in the YRS and BCS suggest that these two segments are better habitat than the ACS and MZS.  相似文献   

5.
Three separate experiments were conducted to investigate the utilization of dietary free amino acids by white sturgeon,Acipenser transmontanus. In the first experiment, sturgeon were fed for 8 weeks with isoenergetic and isonitrogenous diets containing either intact protein, an amino acid mixture, or a neutralized amino acid mixture of similar composition. Sturgeon fed the two amino acid diets grew significantly (p<0.05) less, mainly because of reduced feed intake. In the second experiment, postprandial changes in plasma free amino acids of sturgeon force-fed the above diets were monitored at 2, 4, 6, 8, 12, and 24 h Total plasma amino acids in sturgeon force-fed the intact protein diet showed a gradual increase and reached peak levels at 8 h. In contrast, plasma amino acids of fish force-fed the amino acid diets showed a rapid increase and reached maximal levels at 2 h. In the third experiment, free amino acid diets showed a urine of sturgeon force-fed the three diets was monitored at 4, 8, 12, 16, 20, and 24 h. In all dietary groups, peak excretion of indispensable amino acids was detected at 8 h after feeding but with significantly higher levels from fish force-fed the amino acid diets. Sturgeon force-fed the neutralized amino acid diet excreted 35% less amino acids compared to fish force-fed the non-neutralized diet. Sturgeon force-fed the intact protein diet excreted significantly higher amounts of ammonia. Under amino acid feeding conditions, sturgeon excreted more amino acids in its urine, but the urinary excretion of amino acids was not a major route in dealing with the rapid absorption of dietary free amino acids.  相似文献   

6.
从连续到偶发：中华鲟在葛洲坝下发生小规模自然繁殖   总被引：4，自引：3，他引：4  
中华鲟(Acipenser sinensis Gray)为国家一级重点保护野生动物,典型的溯河洄游产卵鱼类。历史上,中华鲟在长江上游及金沙江下游产卵,由于葛洲坝修建阻隔了其洄游通道,1981年以后在葛洲坝下形成了比较稳定的产卵场,1982―2013年,每年均有自然繁殖发生。由于其栖息生境退化,每年洄游进入长江的中华鲟繁殖亲本逐年减少,2013―2015年连续3年在已知葛洲坝下中华鲟产卵场未监测到中华鲟自然繁殖活动。2016年11―12月的野外监测发现,中华鲟在宜昌葛洲坝下已知产卵场发生了自然繁殖。其中底层网具采集到中华鲟鱼卵(卵膜)67粒、仔鱼22尾;解剖食卵鱼发现,10尾食卵鱼类共摄食中华鲟卵454粒;水下视频观测到5处中华鲟卵黏附底质位点。根据采集到的鱼卵发育期及采集位点推算,产卵时间为2016年11月24日凌晨,产卵场位于葛洲坝大江电厂以下约300 m的江段内,产卵日水温为19.7℃,流量为6610 m3/s,水位为39.7 m。  相似文献   

7.
在葛洲坝下中华鲟(Acipenser sinensis)产卵场连续两年未监测到自然繁殖的情况下,2015年6月在江苏溆浦段发现15尾疑似中华鲟幼鱼。本研究通过形态学和分子生物学方法对该15尾幼鲟进行鉴定。形态学度量结果显示,除1尾个体外,新发现的14尾幼鲟与历史记载的中华鲟野生幼鱼生物学性状完全一致,但其体长和体重低于历史同期出现在该区域的中华鲟。同时采用11个多态微卫星位点,对15尾幼鲟样本和分布于我国的3种鲟鱼,包括30尾中华鲟(A.sinensis)、39尾达氏鲟(A.dabryanus)和33尾施氏鲟(A.dabryanus)进行遗传分析,发现这15尾幼鲟与中华鲟的遗传距离最近(F_(st)=0.039,P0.05),其次为达氏鲟(F_(st)=0.108,P0.05),最远为施氏鲟(F_(st)=0.209,P0.05),从遗传和进化的角度判定该批幼鱼为中华鲟,该结果暗示中华鲟在葛洲坝下游极有可能找到了新的产卵场,为中华鲟的繁殖群体和幼鱼的种群监测提供了依据。遗传多样性分析显示,该批鱼的遗传多样性(SW=1.998)略低于野生中华鲟(SW=1.886),暗示中华鲟幼鱼遗传多样性水平降低,野生亲本的数量仍不容乐观。  相似文献   

8.
Juvenile white sturgeon (Acipenser transmontanus) were fed three isonitrogenous and isoenergetic diets containing either 35% D-glucose (HC), a mixture of 20% dextrin and 10% cellulose (MC), or 23% cellulose (LC), to investigate the effects of dietary carbohydrate on liver function. After 8-week feeding, body weight gain of fish fed the HC diet was consistently higher than that of fish fed the MC and LC diets, but was not significantly different from the MC-fed fish. Fish fed the HC diet had significantly (p < 0.05) higher feed efficiencies and liver glycogen concentrations than fish fed the MC and LC diets. Sturgeon were injected intravenously with 10 mg kg-1 body weight of sulfobromophthalein (BSP) and post-injection blood taken from the caudal vein at 15, 30, 60, and 120 min. No significant differences in plasma BSP concentrations were found among the treatments at these times. Plasma hemoglobin and activities of aspartate and alanine aminotransferase were not affected by the diets. This study suggests that the HC diet does not adversely affect liver function or weight gain. Inclusion of high dietary levels of digestible and inexpensive carbohydrates in commercial sturgeon feeds seems promising, but long-term feeding trials should be conducted to confirm this assertion.  相似文献   

9.
鲟鱼硫酸软骨素的纯化及其特性   总被引：3，自引：0，他引：3  
郑江  关瑞章  黄文树 《水产学报》2008,32(3):478-483
采用乙醇分级沉淀、柱层析等方法纯化了鲟鱼硫酸软骨素,并对提取纯化的鲟鱼硫酸软骨素(色谱纯)与Sigma的鲨鱼硫酸软骨素(色谱纯)进行了比较,探讨了二者在分子量、旋光度、硫酸基团含量和紫外可见光谱等方面的差异.结果表明,鲟鱼硫酸软骨素的重均、数均和Z均分子量、比旋光度、硫酸基团含量均与鲨鱼硫酸软骨素存在显著差异(P<0.05);在紫外可见光谱图中,鲟鱼硫酸软骨素的最大吸收波长在220nm,而鲨鱼硫酸软骨素则在230nm.这些差异表明,鲟鱼硫酸软骨素在生物活性和药用功能方面可能与鲨鱼硫酸软骨素存在区别,并推测鲟鱼硫酸软骨素可能具有较好的抗氧化活性和抗凝血活性.  相似文献   

10.
Hogfish, Lachnolaimus maximus (Walbaum), have multiple traits that confound measuring reproductive potential: they are protogynous, relatively long‐lived harem‐forming fish that spawn daily for months. Additionally, recent evidence demonstrates that size, age and timing of sex change vary on a spatial scale within the study area (West Florida shelf, USA). This study investigates the effect of this spatial variation on hogfish reproductive potential by evaluating spawning seasonality, spawning frequency and batch fecundity using an indeterminate egg production model. Offshore females were larger than nearshore females, and batch fecundity was related in a log‐linear manner to female size. Gonad histology demonstrated a more protracted reproductive period for females offshore (8 months) than nearshore (4 months). Spatial variations in size coincide with ontogeny because hogfish move offshore with growth; however, even after accounting for fish size, offshore females spawned more. In areas where male removal rates are elevated, spawning harems are disrupted; thus, greater fishing effort nearshore may further reduce the reproductive potential of these females. These nearshore and offshore spawning components of the population are not genetically distinct, but instead represent two contingent spawning strategies that likely enhance total population stability and resilience of this stock in the eastern Gulf of Mexico.  相似文献   

11.
  1. Large-scale movement of fishes is a challenge for conservation and management in rivers, especially when individuals can cross jurisdictional boundaries.
  2. Assessing large-scale movement is particularly difficult during early life stages, especially when endangered species are involved. After hatching, free embryos of the federally endangered pallid sturgeon (Scaphirhynchus albus) drift long distances during development. Following the transition to exogenous feeding, individuals may continue to move downstream, resulting in a potential two-step migration.
  3. Tagged age-0 pallid sturgeon were stocked into the lower Missouri River, which provided an opportunity to assess pallid sturgeon dispersal as well as the hypothesized two-step migration. From July 2018 to April 2021, 79 individuals were captured, with most dispersing 200–800 km downstream from the stocking location.
  4. The observed dispersal of pallid sturgeon supports the two-step downstream migration hypothesis. This migration may lead to dispersal into the Mississippi River, which highlights the need for expanded monitoring into the Mississippi River for an effective evaluation of pallid sturgeon recovery actions. This study also reinforces the importance of inter-jurisdictional management and collaboration to better account for the large-scale movement of river fishes.
  相似文献   

12.
Little is known about the movement patterns of gray triggerfish, Balistes capriscus Gmelin, in the northern Gulf of Mexico. To examine fine‐scale movements, gray triggerfish (n = 17) were tagged with transmitters and tracked with the VR2W Positioning System from 17 October 2012 to 9 December 2013. Most (76%) tagged fish survived and were tracked for 1–57 weeks. Tagged fish showed significantly larger home ranges and core areas in autumn than winter–spring and during day than night. Seasonal movement patterns were positively correlated with water temperature. Gray triggerfish stayed close to the reef (mean ± SD distance = 35.9 ± 28.4 m) and showed high site fidelity (64%) and high residency (>57 weeks). These patterns emphasise the importance of structured habitat for this species and suggest that artificial reef building in the northern Gulf of Mexico has enhanced this population.  相似文献   

13.
The size of anadromous whitefish caught with dip nets in the River Tornionjoki in the northern part of the Gulf of Bothnia has decreased during recent decades. To find an explanation for this trend, ascending whitefish were sampled in the lower part of the river in August 2016, and they were divided into two groups according to fish length. The length of the SMALL group was ≤ 32 cm (n = 32) and that of the LARGE group ≥ 33 cm (n = 65). The elemental analysis of otoliths revealed that the barium concentration was clearly higher in otoliths from the SMALL group compared to the LARGE group. This indicates that the fish in the LARGE group had migrated to feed further south in the Gulf of Bothnia, with a higher salinity, than the fish in the SMALL group. Because of this migration difference, and a decline in the gillnet effort, especially in the feeding areas near the river mouth, it is assumed that proportionally more fish in the SMALL group are able to ascend the river to spawn than previously, thus decreasing the mean size. At the same time, the heavy gillnet fishery in the south removes fish from the LARGE group.  相似文献   

14.
长江口中华鲟幼鱼的生长特性   总被引：11，自引：4，他引：11  
毛翠凤  庄平  刘健  张涛  章龙珍 《海洋渔业》2005,27(3):177-181
2004年5~8月中华鲟幼鱼降河洄游途中在长江口聚集期间,收集到196ind幼鱼样本,分析研究了其生长特点。结果显示,中华鲟幼鱼在长江口逗留期间生长迅速,体长和体重分别从5月下旬刚到达长江口时的16.68±3.27cm和28.69±16.06g增加到8月份入海时的31.90±7.77cm和236.77±176.64g,体长增长1.91倍,体重增加8.25倍。中华鲟幼鱼体重与体长呈幂函数关系,其幂指数b值在5月和8月小于3,此时表现出异速生长。b值在6月和7月接近于3,呈等速生长。6月和7月的肥满度也高于5月和8月。表明6月和7月的生长情况要好于5月和8月。这一现象可能是中华鲟幼鱼在5月和8月有2次生活环境改变和食性变化所导致。  相似文献   

15.
Mickle PF, Schaefer JF, Adams SB, Kreiser BR. Habitat use of age 0 Alabama shad in the Pascagoula River drainage, USA. Ecology of Freshwater Fish 2010: 19: 107–115. © 2009 John Wiley & Sons A/S
Abstract – Alabama shad ( Alosa alabamae ) is an anadromous species that spawns in Gulf of Mexico drainages and is a NOAA Fisheries Species of Concern. Habitat degradation and barriers to migration are considered contributing factors to range contraction that has left just the Pascagoula River drainage population in Mississippi. We studied juvenile life history and autecology in three rivers within the drainage. We collected fish, habitat and physicochemical data in three habitat types (sandbar, open channel and bank) from June to October 2004–2006. Sandbar habitat was favoured by smaller individuals early in the year. Catch per unit effort (CPUE) decreased through the summer as larger fish began occupying bank and open channel habitat. The most parsimonious model of abundance included year and river variables, while patterns of presence and absence were best explained by river, habitat type and physiochemical variables. While all three rivers in the drainage contained Alabama shad, fish were less abundant and had lower condition values in the Chickasawhay River. Earlier work suggested the Alabama shad may gradually move downstream towards the Gulf of Mexico in their first year. However, we found no evidence of this and captured large fish high in the drainage late in the year.  相似文献   

16.
Abstract Telemetry was used to examine spawning migration of sea trout, Salmo trutta L. (n = 126), in two rivers in northern Sweden. The spawning areas defined by radio‐tagged fish differed between the river systems. In the River Vindelälven, sea trout spawned in the main stem and 80% of tagged individuals returned to areas where hatchery‐reared juveniles had been previously stocked. In the River Piteälven, 74% of tagged sea trout ascended tributaries for spawning. Tagged fish were categorised into three groups of migratory pattern. cart (classification and regression tree) analysis indicated that distance from tagging location to spawning site (Sdist) explained the migratory patterns. Large Sdist separated fish with stepwise upstream migration from those with up‐ and downstream migrations and one‐directional direct migration. Fish tagged early in the season migrated the longest distance to spawning areas. Stocking locations and sex explained the large search behaviour up‐ and downstream in the rivers. The findings are important for the sustainable management of sea trout in the Gulf of Bothnia.  相似文献   

17.
  1. The white mullet, Mugil curema, is a widely distributed euryhaline species, the migratory behaviour of which is poorly understood. The objective of this work was to study the large-scale habitat use of this species for the first time. Several environments were considered, such as euryhaline and hypersaline lagoons, the sea, and a river, distributed in the Central Pacific (Mexico) and Atlantic (Gulf of Mexico, Caribbean Sea-Venezuela, and north-eastern Brazil).
  2. Otolith core-to-edge Sr/Ca ratios of 163 fish, determined by laser ablation inductively coupled plasma mass spectrometry, were used to study the salinity-habitat migration history of the fish. Fish from Mexico (Tamiahua Lagoon, n = 4; Alvarado Lagoon, n = 2), Venezuela (n = 1), and Brazil (n = 12) (11.1% of the total) showed high Sr/Ca values at early life stages and were classified as marine estuarine opportunists. Two specimens (from Alvarado Lagoon and Balsas River, Mexico) showed Sr/Ca values consistently below the high salinity guide value (salinity < 33.5). For the rest of the fish (87.1%), the Sr/Ca ratio suggested a displacement from the estuary towards the sea or hypersaline environments, and so these fish were classified as estuarine migrants.
  3. A change-point analysis identified six individuals with a single stable otolith Sr/Ca signature through ontogeny (three from Brazil, one from Venezuela, and two from Tamiahua Lagoon, Mexico), suggesting limited displacement between environments with different salinities. The rest of the individuals showed between two and 10 changes in stable Sr/Ca signatures (mean = 4.07 ± 1.85). The highest number of changes in Sr/Ca ratio (4.87 ± 1.1) was found in fish from Laguna Madre (Mexico) and the lowest was found in fish from Brazil (3.27 ± 1.70) (H = 19.8, p = 0.002).
  4. Otolith Sr/Ca time series suggest that the migratory estuarine pattern is the most common throughout the study area. This work highlights that the sustainable use of M. curema depends on the conservation of estuaries and the corridors between them and other environments such as lagoons, rivers, mangroves and the sea.
  相似文献   

18.
Two studies were conducted using 5- to 6-month-old juvenile (mean weight: 3-4 g) white sturgeon, Acipenser transmontanus, to examine the effects of density and other stressors on manifestation of disease caused by the white sturgeon iridovirus (WSIV). In the first study, replicate groups of Snake River white sturgeon were stocked at three densities (953, 1,907, and 3,178 fish/m3) in 0.31-m3 fiberglass aquaria with spring water flow through of 30.0 L/minute. No significant (P > 0.05) differences were observed among the three groups during the initial 6-week period. However, the high density group cumulative mortality was significantly (P < 0.05) greater than the mortality detected in the other groups at 59 days. Pathognomonic signs of WSIV were detected in moribund fish from each group by histological evaluation; however, no virus was isolated. These results suggested that maintaining low sturgeon densities in fish younger than I year may be a prudent strategy for minimizing mortality caused by WSIV. In the second study, triplicate or replicate groups of Kootenai River white sturgeon that had been transported for approximately 14 hours at 2-6°C, prior to acclimation at lS°C, were stocked at high and low densities previously tested. No signs of WSIV or abnormal mortality were observed during the initial 2-week period. However, after 36 days the mortality increased to 10-18% and 14-18% in the low and high density groups, respectively, and signs of WSIV disease were detected in moribund fish examined from each treatment by histological evaluation. The presence of the virus was further confirmed by electron microscopy of gill tissue. Although fish density did not appear to affect the occurrence of disease or cumulative mortality, the results suggested that a stressor (e.g., handling, transport, and temperature) in subyearling sturgeon may enhance clinical manifestation of WSIV.  相似文献   

19.
Depletion of sturgeon stocks world-wide has increased interest in aquaculture-based restoration programmes. The Caspian Sea Sturgeon Ranching Programme (SRP) of the former Soviet Union represents a unique opportunity to evaluate expense, benefits and potential ecological and genetic effects of such restoration programmes. The SRP was initiated in the 1950s to compensate for lost spawning habitat in the Volga River and elsewhere. After its completion in 1962, the Volgograd Dam reduced spawning grounds in the Volga River system, the principal spawning tributary of the Caspian Sea, by ∼80%. For two of the three commercial sturgeon species (Russian sturgeon, Acipenser güldenstädti , and stellate sturgeon, A. stellatus ), yields improved after the imposition of the 1962 moratorium on sturgeon harvests in the Caspian Sea. Volga River fisheries were managed for spawning escapement. Although imprecisely known, the contribution of the millions of stocked Russian and stellate juveniles during 1962–91 was most likely important to sustaining fisheries, although less so (contributing to <30% of the adult stock) than natural recruitment. Apparently, reduced spawning grounds, supplemented with artificial spawning reefs were sufficient to support reproduction and large fishery yields of Russian and stellate sturgeons. For beluga sturgeon, Huso huso , harvests in the Volga River were nearly all dependent upon hatchery stocking. Beluga sturgeon spawning grounds were mostly eliminated with the construction of the Volgograd Dam. Without the hatchery programme, beluga sturgeon in the Volga River and Caspian Sea would in all likelihood have been extirpated. Currently, sturgeons are severely depleted in the Volga River and Caspian Sea due to poaching and lack of co-operation between countries exploiting the species. Aquaculture-based restoration in Russia is now viewed a chief means of rebuilding stocks of Caspian Sea sturgeons.  相似文献   

20.
基于标志放流信息的长江口中华鲟降海洄游和分布特征   总被引：1，自引：0，他引：1  
中华鲟(Acipenser sinensis)为国家一级重点保护野生动物。2004—2014 年在长江口水域标志放流中华鲟 12570 尾, 标志回捕中华鲟 24 尾次, 接收 18 枚落式卫星数据回收标志(PAT)信息。本研究根据标志放流信息, 分析研究长江口标志放流中华鲟降海洄游和分布特征。研究结果表明: (1)长江口标志放流中华鲟分布于经度跨度 7°, 纬度跨度 9°的长江口水域和东海及黄海海域, 主要聚集分布区为长江口水域和舟山群岛海域; (2)标志放流中华鲟具有显著的降海洄游趋势, 放流后短期滞留在长江口淡水环境, 7 d 后具有进入海洋的行为; (3)长江口标志放流中华鲟进入海洋后, 其迁移方向会出现随机性, 在迁移过程中具有折返、转向、停滞的特征。本研究通过对长江口增殖放流的中华鲟标志回捕信息开展研究, 旨在揭示中华鲟降海洄游和分布特征, 为中华鲟资源保护提供科学依据。  相似文献   

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