水温和体重对白斑红点鲑临界游泳速度和游动耗氧率的影响

为了揭示水温和体重对白斑红点鲑(Salvelinus leucomaenis)临界游泳速度和游动耗氧率的影响, 利用试验生态学方法测定了不同体重(1龄组、2龄组和3龄组)的白斑红点鲑在4、8、12、16、20和24℃共6个水温的临界游泳速度和游泳耗氧率。结果表明: 水温和体重对临界游泳速度的单独效应均显著(P0.05), 但水温和体重交互作用效应却不显著(P0.05), 在相同水温下白斑红点鲑临界游泳速度均随着年龄的增长(体重增加)而增加。水温4℃时3个年龄组白斑红点鲑临界游泳速度均最低, 分别为(21.61.06)、(22.930.61)和(30.271.29) cm/s, 随着水温的升高临界游泳速度均不断增加, 当水温升高到16℃时临界游泳速度达到最大值, 分别为(39.60.80)、(46.800.80)和(53.731.22) cm/s, 此后随着水温进一步升高到20℃, 临界游泳速度虽出现略微降低, 但经统计分析16℃和20℃时临界游泳速度无显著性差异(P0.05), 当水温达到24℃时却出现明显降低。水温和流速以及二者的交互作用对游泳耗氧率的影响均达到显著水平(P0.05), 白斑红点鲑在适宜的相同水温和流速时体重越大其游泳耗氧率越低, 整体观察3个年龄组白斑红点鲑鲑游泳耗氧率均随着水温和流速的增高而增高, 但当水温和流速升高到一定值游泳耗氧率却出现降低。研究得出体重较大的个体在相同水温下抵抗水流的游泳能力较强, 3个年龄组白斑红点鲑适宜的最高水温不应超过20℃, 最高流速依次不应超过32、40和48 cm/s。       

应用于鱼道设计的马口鱼(Opsariichthys bidens)游泳能力

马口鱼(Opsariichthys bidens)广泛存在于长江流域,是体型较小的重要经济鱼种。游泳耐力、临界游泳速度、冲刺游泳速度是鱼类重要的游泳能力参数。本文利用鱼类游泳能力测试环形水槽,在实验水温21.4±0.3℃条件下,用固定流速法对128尾(全长TL:9.60~15.10 cm)测试鱼进行游泳耐力测试,用流速递增法分别对31尾(TL:9.16~15.91cm)、56尾(TL:8.78~16.81 cm)测试鱼进行临界游泳速度、冲刺游泳速度测试。结果表明:在游泳耐力测试中,84%以上测试鱼持续游泳时间集中分布在0~10 min和200 min的范围内;疲劳时间(E)、游泳速度(V)、全长(TL)之间的关系可拟合为lg E=1.603-0.025V+0.146TL(R~2=0.562,P0.001),根据拟合关系式预测全长为9.60 cm(最小长度)测试鱼可连续通过的鱼道长度与允许最大鱼道内平均水流速度的关系曲线为V_(fmax)=223.3973-17.3609ln(d-0.0130);测试鱼的临界游泳速度值为61.07~120.03 cm·s~(-1)(相对临界游泳速度6.57~12.65 BL·s~(-1));冲刺游泳速度范围为65.03~155.07 cm·s~(-1)(相对冲刺游泳速度5.31~17.95 BL·s~(-1)),78%的实验鱼其冲刺游泳速度大于1 m·s~(-1),平均冲刺游泳速度约为平均临界游泳速度的1.23倍。本试验方法和结果可为鱼道设计提供相关依据。     

人工标志放流中华鲟幼鱼的降河洄游

1998— 2 0 0 2年期间 ,向长江放流人工繁殖中华鲟 2月龄稚鲟 (全长 7 5— 17 0cm) 17 5 2万尾 ,其中 7795 7尾用CWT进行标记 ;14月龄幼鲟 (全长 5 5 0— 98 0cm) 4 0 0尾 ,全部用外挂银牌和CWT双重标记。放流后沿长江及沿海收集中华鲟稚鲟和幼鲟样本 ,4年共回收稚鲟样本 6 4 0 0尾 ,幼鲟样本 13尾 ,检测到携带标记的稚鲟和幼鲟各 13尾。人工放流的幼鲟降海洄游的速度平均达到 2 8 6km/ 2 4h(7 1— 10 0 2km/ 2 4h) ,回捕时离放流点的距离从 346—2 4 5 9km ,平均 16 0 0km ,回捕的标志幼鲟有 4 6 2 %的个体来自海区。初步估算出 1999年和 2 0 0 0年人工放流个体在长江口幼鲟种群中的贡献率分别为 2 2 81%和 0 997%。结果表明 ,人工放流中华鲟稚鲟和幼鲟的生长、洄游及分布与自然种群没有明显差异。放流较大规格的幼鲟有利于提高成活率 ,而目前长江中华鲟种群的补充仍以自然繁殖种群为主。     

厦门海域放流中华鲟的迁移和分布

2010～2013年,在厦门九龙江口共标志放流了258尾4～12龄中华鲟(全长142～210 cm),其中13尾个体使用了弹出式卫星档案标志(MK 10-PAT).放流后共收集到21尾个体误捕信息以及10尾卫星标志个体的迁移和分布位点信息,结果显示,中华鲟分布位点主要位于中国沿海大陆架水域,集中分布位点为厦门至舟山群岛之间的近海区.除3尾个体离岸距离为350,41和29 km外,其余个体与海岸线距离均在15 km范围内;从分布纬度来看,向南迁移的纬度范围为1.366°,到达南海海域,向北最远迁移的纬度范围为14.539°,到达朝鲜东部海域,纬度跨度为15.905°.沿大陆架的直线迁移距离和速度分别为449/378 km(卫星标志/回捕个体,范围=11～2205/3～1488 km)和0.18/0.18 km/h(卫星标志/回捕个体,范围=0.03～0.73/0.02～1.07 km/h),卫星遥测中华鲟与回捕中华鲟的迁移速度和迁移距离均没有显著性差异.1尾卫星标志中华鲟的详细迁移监测结果表明,该尾鱼放流后134 d共完成了2205 km距离的迁移,平均迁移速度为0.52 km/h(范围=0.23～7.53 km/h).中华鲟的栖息水温和栖息水深分别为22.8℃(范围=17.2℃～29.5℃)和22.19 m(范围=11.25～32.25 m).中华鲟的海区迁移和分布与水温、盐度、水深和饵料等环境因素有关.研究结果有助于弄清中华鲟在海区的空间分布特征和迁移速度,为后期深入研究中华鲟在海区的生境选择特征提供有价值的数据,也为该物种的海洋保护和管理提供理论依据.     

北江间的年龄与生长特征

于2007年4月至2009年3月间,在广东北江中上游地区采集间(Hemibarbus medius)样本640尾,以鳞片作为年龄鉴定材料,对其种群的年龄与生长特征进行了研究。结果表明,间鳞片上年轮结构清晰,前区主要表现为疏密型,而侧区主要为切割型;鳞片的边缘生长率表明,间年轮的形成期主要为3~4月份。样本由0+~6+龄7个龄组组成,其中,雌性由1+~6+龄6个龄组组成,主要为1+~4+龄;而雄性由1+~5+龄5个龄组组成,主要为1+~3+龄;在4+~6+龄个体中,雌性78尾,雄性27尾,雌性显著多于雄性。体长(L,cm)与体重(W,g)的关系为W=0.011L3.149(♀)、W=0.011L3.135(♂),协方差分析表明,雌雄个体体长与体重关系的差异不显著,所有样本体长与体重的关系式为W=0.011L3.148。体长与鳞长(R,mm)呈幂函数及直线关系,关系式分别为L=6.387R0.853、L=4.569R+2.587。拟合的von Bertalanffy生长参数为L∞=29.855 0 cm,k=0.223 1,W∞=483.889 8 g,t0=﹣0.928 2龄。对理论体长与实测体长、理论体重与实测体重进行χ~2检验,两者的差异均不显著,表明von Bertalanffy生长方程能较好地拟合间的生长。体重生长的拐点年龄为4.21龄,拐点体长约为20.37 cm,体重约为166.19 g。作为渔业保护对策,建议起捕年龄3龄以上或体长17 cm以上的个体。     

据于矢耳石Sr/Ca值的长江日本鳗鲡迁移格局多样性分析(英文)

长江口是中国日本鳗鳗苗的主要产区和仅存的成鳗渔业水域。日本鳗自长江河口至上游金沙江近3000km干流及许多支流中都有分布,但其迁移行为却不为人了解。该文分析了2008年9～11月采自长江靖江段(31o30′N,120o42′E)的153尾银色鳗样本的生物学特征,测定了其中27尾标本的矢耳石Sr/Ca值。结果显示,153尾样本中有雌性85尾、雄性68尾,雌雄性比1:0.8。雌性由3～7(平均5.52)龄组成,平均体长(669±80)mm,体重(555±229)g,丰满度1.77±0.22,性腺指数(GSI)1.32±0.31。雄性由3～5(平均4.38)龄组成,平均体长(518±51)mm,体重(234±76)g,丰满度1.62±0.18,GSI0.21±0.11。雌性的这些生物学参数均显著大于雄性(P<0.05)。依据矢耳石线鳗标志轮平均Sr/Ca值(7.99±1.05)×10-3进行判断,有17尾(即62.96%个体)为"淡水型",10尾(即37.04%个体)为"河口型"。16尾雌性中有13尾(即81.25%)为"淡水型",3尾为"河口型"。11尾雄性中仅36.36%为"淡水型",63.64%为"河口型"。对每个生长层组的Sr/Ca值分析表明,雌雄间2龄时无显著差异,但3龄、4龄和洄游龄组都有显著或极显著的差异,预示着2龄时两者的栖息水域比较一致,但后来出现了明显栖息地分化。     

绥芬河大麻哈鱼个体生物学研究

研究以2012至2017年在绥芬河东宁段采集的447尾大麻哈鱼(Oncorhynchus keta Walbaum)为材料,对其年龄与生长及繁殖特性等个体生物学特征进行研究分析。结果表明:绥芬河大麻哈鱼种群由1~+-5~+龄5个年龄组构成,其中雌性个体以3~+龄为主,雄性个体以2~+龄为主。大麻哈鱼雌、雄个体的体长-体重关系分别为:W=0.0082×L~(3.0604);W=0.0076×L~(3.0746),均属匀速生长类型;采用Von Bertalanffy生长方程拟合得到3~+龄大麻哈鱼雌、雄个体的叉长生长方程分别为:L_(t,F)=141.64×e~(-0.11)·(t+1.55));L_(t,M)=119.51×e~(-0.13·(t+1.45))。利用逻辑斯蒂方程估算大麻哈鱼雌、雄个体初次性成熟叉长(L_(50))分别为51.53和42.15 cm。ARSS分析显示雌、雄个体的L_(50)差异显著;大麻哈鱼的绝对繁殖力(F)、相对叉长繁殖力(F_L)和相对体重繁殖力(F_W)分别为3412粒、52.42粒/cm和1.17粒/g;F与叉长、体重、性腺重呈显著正相关关系,GSI与叉长、体重、F成显著负相关关系;F与叉长、体重的幂函数关系方程式分别为:F=0.0311×L~(2.7745)(R~2=0.638)和F=1.946×W~(0.9374)(R~2=0.704)。本研究为绥芬河大麻哈鱼资源保护工作提供基础资料。     

塔里木河叶尔羌高原鳅繁殖生物学研究

2010年7月至2011年12月,在塔里木河阿拉尔段采集叶尔羌高原鳅Triplophysa (Hedinichthys) yar-kandensis (Day)940尾(除性别未辨个体外)用于繁殖生物学研究。种群雌雄比为0.85︰1,最小性成熟,雌性个体体长为8.2 cm,体重为7.4 g,年龄为3龄;雄性个体体长为6.5 cm,体重为3.4 g,年龄为2龄。叶尔羌高原鳅卵径分布呈单峰形,推测应属于同步产卵类型。计算了88尾Ⅳ-Ⅴ期雌鱼的怀卵量,其体长范围30-195 mm,体重范围3.59-114.04 g,绝对繁殖力为1101-56320(9944±5487)粒,相对繁殖力为824-1140(982±158);塔里木河阿拉尔段叶尔羌高原鳅种群繁殖力(Fp)为403.46万粒。     

水族馆养殖中华鲟血细胞指标的变化

血细胞是临床健康的重要指标。本文对北京海洋馆养殖的40尾中华鲟（Acipenser sinensis）外周血细胞组成进行研究,研究对象包括超过30龄、18龄、16龄、15龄、11龄、7龄和4龄共7个龄组,并分析比较不同年龄、性腺快速发育前后以及处于疾病前后血细胞指标变化,希望应用于健康评价。结果表明,1）外周血红细胞总数（RBC）平均为（5.56 ± 1.19）× 1011/L,18龄和11龄与其他龄组之间存在显著性差异（P < 0.05）,超过30龄组血细胞比积（HCT）和血红蛋白（HB）值显著高于其他龄组（P < 0.05）;2）白细胞总数（WBC）平均为（16.53 ± 4.94）× 109/L,18龄与4龄间存在显著差异,且分别与其他龄组间存在显著性差异（P < 0.05）。3）白细胞分类计数（DLC）中各类型白细胞平均所占百分比分别为,大淋巴细胞（LLYM）5.26% ± 3.95%、小淋巴细胞（SLYM）77.74% ± 11.73%、嗜中性粒细胞（NEU）9.40% ± 7.98%、嗜酸性粒细胞（EOS）1.90% ± 2.06%和单核细胞（MON）5.50% ± 4.00%,超过30龄和4龄间显著差异,且分别与其他龄组间存在显著性差异（P < 0.05）。4）性腺进入快速发育阶段后,红细胞总数、血细胞比积和白细胞总数较发育前均显著增加（P < 0.05）,血红蛋白值有增加但差异不显著。5）疾病中华鲟白细胞总数显著增高（P < 0.05）并伴随红细胞各指标降低,白细胞数增加幅度达90%,分类计数中中性粒细胞和单核细胞比例显著变化（P < 0.05）。中华鲟快速发育阶段及疾病状态的血细胞组成不同,血细胞密度的变化以及分类计数的差异可及时判断中华鲟健康状况,结果对中华鲟的健康评价与保育研究有重要的参考意义。     

西藏浪错兰格湖裸鲤种群繁殖生物学特征

2017年7月至2018年6月,于西藏自治区昂仁县浪错采集兰格湖裸鲤(Gymnocypris chui)307尾,开展种群繁殖生物学研究。结果显示,浪错兰格湖裸鲤在3～5月性成熟系数较高。雌性最小性成熟个体年龄为7龄,体长217mm,体重122.68g,成熟系数为3.92%;雄性最小性成熟个体年龄为6龄,体长198 mm,体重91.93 g,成熟系数为3.34%。其平均成熟卵径为2.18 mm,卵径分布为单峰型。绝对繁殖力为862～8 933粒/尾,平均绝对繁殖力为(2 885±2 765)粒,相对繁殖力为7～43粒/g,平均相对繁殖力为(15±11)粒/g。绝对繁殖力与体长和体重呈显著正相关,相对繁殖力与体长、体重的相关性不显著。繁殖群体性比(♀︰♂)为1︰0.967,符合1︰1比例。     

Effect of triclosan exposure on mortality and behavioral changes of Poecilia reticulata and Danio rerio

Triclosan (TCS), a chemical used for its antibacterial properties, is an ingredient in many detergents, soaps, deodorants, cosmetics, antimicrobial creams, toothpastes, and an additive in various plastics and textiles. The behavioral changes at different TCS concentrations (0.001–0.002–0.005–0.01–0.02–0.05–0.1–0.2–0.5 mg/L) were determined for the each test organisms in the study. The synthetic freshwater has temperature 20 ± 2°C, dissolved oxygen 7.0 ± 2 mg/L, pH 7.0–8.0. All experiments were replicated three times, in 14 h light, 10 h dark incubations, 10 fishes were put to each aquarium. In hourly and daily observations, times of dead and number for Poecilia reticulata, Danio rerio were recorded. Behavioral changes of Poecilia reticulata and Danio rerio were observed, such as fast-moving, uncontrolled swimming, trying to escape out of the water, vertical action to the water surface, loss of balance, respiratory difficulties, chills, and inversion.     

The swimming abilities of recently settled post-larvae of Sillaginodes punctata

Sixty-four post-larvae of the King George whiting Sillaginodes punctata were tested in swimming chambers, against one of five flow-through velocities (2, 4, 6, 8 or 10 cm s ⁻¹) for up to a maximum of 120 min. Fish were determined by regression to have an FV₅₀ (50% fatigue velocity) of 6.0 cm s⁻¹. No fish survived the full 120 min at 10 cm s⁻¹. Sixteen individuals were tested in a swimming chamber against a flow-through velocity of 6 cm s ⁻¹ and allowed to swim to exhaustion. Fish swam between 25 and 538 min with a peak at c . 6–8 h. Total swimming time was not correlated with standard length of fish although the size range examined was narrow. Relative to recent studies on the swimming abilities of late-stage larvae of reef fishes, this study indicates that post-larval King George whiting are weak swimmers. The weak swimming ability of post-larval King George whiting is consistent with studies showing passive dispersal and recruitment of this species.     

Comparative swimming abilities of fed and starved larval largemouth bass (Micropterus salmoides)†

Sustained swimming abilities of fed and starved larval largemouth bass (Micropterus salmoides L.) were compared in the first week after swimming initiation. Fed larvae improved to a sustained velocity of 4·0 cm/sec while starved larvae attained a velocity of only 1·5 cm/sec. Swimming behaviour for fed and starved larvae was quantified for number of moves, average distance/move, and total distance for all moves in 1 min intervals. Fed larvae were always more active than starved larvae, although real differences did not appear until the 4th day after swimming initiation.     

切除眼柄对加速克氏原螯虾卵巢发育进程的组织学研究

应用组织切片和透射电镜技术研究眼柄切除对加速克氏原螯虾(Procambarus clarkii)卵巢发育进程的影响。实验分成4组,选取眼柄切除15 d和30 d两个时间点进行。切除眼柄30 d后,雌虾体长增长显著,从(11.50±2.30)cm增长至(18.20±3.40)cm(P0.05),性腺指数(GSI)从4.56%±2.81%增长至8.05%±2.51%(P0.05),体重和螯肢长也有所增长(P0.05)。电镜观察发现卵母细胞从发育Ⅱ期迅速度过Ⅲ期进入到Ⅵ期阶段,卵母细胞体积变大,变圆;液泡压缩变小;卵黄颗粒加速积累,逐渐占满整个胞内空间;滤泡细胞胞质从黏稠变稀薄。这些结果表明,切除眼柄在短期内显著加快卵母细胞内卵黄颗粒的积累,并且加快个体生长。     

Behavior of red king crab larvae: Phototaxis,geotaxis and rheotaxis

Zoeae of Paralithodes camtschatica were positively phototactic to white light intensities above 1 × 10¹³ q cm^?2 s^?1. Negative phototaxis occurred at low (1 × 10¹² q cm^?2 s^?1), but not high intensities (2.2 × 10¹⁶q cm^?2 s^?1). Phototactic response was directly related to light intensity. Zoeae also responded to red, green and blue light. Zoeae were negatively geotactic, but geotaxis was dominated by phototaxis. Horizontal swimming speed of stage 1 zoeae <4 d old was 2.4 ± 0.1 (SE) cms^?1 and decreased to 1.7 ± 0.1 cm s^?1 in older zoeae (P <0.01). Horizontal swimming speed of stage 2 zoeae was not significantly different from ≥4 d old stage 1 zoeae. Vertical swimming speed, 1.6 ± 0.1 cm s^?1, and sinking rate, 0.7 ± 0.1 cm s^?1, did not change with ontogeny. King crab zoeae were positively rheotactic and maintained position in horizontal currents less than 1.4 cm s^?1. Starvation reduced swimming and sinking rates and phototactic response.     

Surfacing activity and food utilization in a tropical air-breathing fish exposed to different temperatures

Reared in tubular aquaria containing different depths of water (2.5, 5.0, 15.5, 31.0 and 40.0 cm), the obligatory air-breathing fish Ophiocephalus striatus (760 mg; 4.5 cm L) was forced to swim vertically a longer or shorter distance per surfacing. Interaction of temperature (17, 22, 27, 32 and 37°C) and aquarium depth reveals that surfacing frequency of the fish, fed ad libitum on Tilapia muscle, increased with increasing aquarium depth, but the increase was significant only at 27 and 32°C; in the starving series, the frequency was not depth-dependent at any temperature. Owing to the sustained surfacing activity and the consequent fatigue, the test individuals ‘hung’ to the surface for a definite period. Hanging frequency was temperature-dependent, but not a depth-dependent activity either in the starving or feeding series. At any temperature and aquarium depth, the feeding series hung more frequently than the starving series. Hanging duration increased from about 1 hr/day in either series at 17°C to 6 and 18 hr/day in the feeding and starving series at 37°C. At any tested temperature, distance swum by the feeding and starving series was a depth-dependent activity. The feeding series at 32°C exhibited the maximum swimming speed of 2 L/sec for 4.8 hr/day in the 40 cm depth. With increasing temperature and depth, feeding rate increased (from 24 to 225 g cal/g live fish/day); between 17 and 27°C, it was more a temperature-dependent activity. The highest rate (47 g cal / g/day) and efficiency (27%) of conversion were observed at 32°C; whereas the efficiency was depth-dependent, the rate was not. Oxygen uptake was a temperature-dependent activity; aquarium depth played a secondary role. Briefly, O. striatus in deeper aquaria consumed significantly more food and converted lesser, as it surfaced more frequently and swam longer distance, dissipating more energy on metabolism and swimming activity. Hence, culturing O. striatus in shallow waters at the optimum temperature of 32°C will be advantageous. This work was supported by the University Grants Commission's (New Delhi) grant to Dr. T. J. Pandian: Grant No. F. 23-210/75 (Sr II) for which appreciation is expressed.     

Ontogeny of critical and prolonged swimming performance for the larvae of six Australian freshwater fish species

Critical (<30 min) and prolonged (>60 min) swimming speeds in laboratory chambers were determined for larvae of six species of Australian freshwater fishes: trout cod Maccullochella macquariensis, Murray cod Maccullochella peelii, golden perch Macquaria ambigua, silver perch Bidyanus bidyanus, carp gudgeon Hypseleotris spp. and Murray River rainbowfish Melanotaenia fluviatilis. Developmental stage (preflexion, flexion, postflexion and metalarva) better explained swimming ability than did length, size or age (days after hatch). Critical speed increased with larval development, and metalarvae were the fastest swimmers for all species. Maccullochella macquariensis larvae had the highest critical [maximum absolute 46·4 cm s^?1 and 44·6 relative body lengths (L_B) s^?1] and prolonged (maximum 15·4 cm s^?1, 15·6 L_B s^?1) swimming speeds and B. bidyanus larvae the lowest critical (minimum 0·1 cm s^?1, 0·3 L_B s^?1) and prolonged swimming speeds (minimum 1·1 cm s^?1, 1·0 L_B s^?1). Prolonged swimming trials determined that the larvae of some species could not swim for 60 min at any speed, whereas the larvae of the best swimming species, M. macquariensis, could swim for 60 min at 44% of the critical speed. The swimming performance of species with precocial life‐history strategies, with well‐developed larvae at hatch, was comparatively better and potentially had greater ability to influence their dispersal by actively swimming than species with altricial life‐history strategies, with poorly developed larvae at hatch.     

鲢幼鱼在不同水流速度下的暴发-滑行行为策略

在水温（18±1）℃的条件下,以全长（11.70±0.57）cm的鲢（Hypophthalmichthys molitrix）幼鱼为研究对象,测定其不同流速（16.5、22.0、27.5、33.0、38.5、44.0、49.5和55.0 cm/s）下的持续游泳时间、调头百分比和暴发-滑行运动数据。结果表明,鲢的平均持续游泳时间先随流速的增加而减小,后随流速的增加而增加。当流速33.0 cm/s时,平均持续时间最短为118.6min,其中各组试验鱼的最大可持续游泳时间均可达到200min。调头百分比随流速的增加迅速减小,当流速≥44.0 cm/s时,不再出现调头行为。暴发-滑行游泳的平均暴发时间随流速的增加呈上升趋势（y=0.03x+2.64,R2=0.92,P<0.05）。平均对地暴发距离均在30-45 cm,没有显著性差异（P>0.05）,平均绝对暴发距离存在极显著性差异,且随流速的增加而增加（y=4.98x-5.63,R2=0.98,P<0.001）。平均对地暴发速度没有显著性差异（平均对地平均速度和最大速度分别在9-12 cm/s、12-16 cm/s,P>0.05）。平均绝对暴发速度与水流速度之间存在线性正相关关系（平均绝对平均暴发速度:y=0.98x+10.74,R2=1.00,P<0.001;平均绝对最大暴发速度:y=1.02x+13.75,R2=0.99,P<0.001）。研究表明鲢在不同的流速下采取的暴发-滑行行为策略不同。     

Increasing ocean temperatures reduce activity patterns of a large commercially important coral reef fish

Large‐bodied fish are critical for sustaining coral reef fisheries, but little is known about the vulnerability of these fish to global warming. This study examined the effects of elevated temperatures on the movement and activity patterns of the common coral trout Plectropomus leopardus (Serranidae), which is an important fishery species in tropical Australia and throughout the Indo West‐Pacific. Adult fish were collected from two locations on Australia's Great Barrier Reef (23°S and 14°S) and maintained at one of four temperatures (24, 27, 30, 33 °C). Following >4 weeks acclimation, the spontaneous swimming speeds and activity patterns of individuals were recorded over a period of 12 days. At 24–27 °C, spontaneous swimming speeds of common coral trout were 0.43–0.45 body lengths per second (bls^?1), but dropped sharply to 0.29 bls^?1 at 30 °C and 0.25 bls^?1 at 33 °C. Concurrently, individuals spent 9.3–10.6% of their time resting motionless on the bottom at 24–27 °C, but this behaviour increased to 14.0% at 30 °C and 20.0% of the time at 33 °C (mean ± SE). The impact of temperature was greatest for smaller individuals (<45 cm TL), showing significant changes to swimming speeds across every temperature tested, while medium (45–55 cm TL) and large individuals (>55 cm TL) were first affected by 30 °C and 33 °C, respectively. Importantly, there was some indication that populations can adapt to elevated temperature if presented with adequate time, as the high‐latitude population decreased significantly in swimming speeds at both 30 °C and 33 °C, while the low‐latitude population only showed significant reductions at 33 °C. Given that movement and activity patterns of large mobile species are directly related to prey encounter rates, ability to capture prey and avoid predators, any reductions in activity patterns are likely to reduce overall foraging and energy intake, limit the energy available for growth and reproduction, and affect the fitness and survival of individuals and populations.