斑马鱼报警反应产生发育阶段的研究

鱼类在遭受捕食后,受损的表皮会释放大量的化学信号物质,同种其它个体嗅到这些化学信号后会作出躲避反应,称为报警反应(alarm response),报警反应通常出现在一定的发育阶段。采用斑马鱼(Dinio rerio)同种碾碎提取物(处理组,质量浓度为10-6g·L-1)作为报警物质,并设3个对照组:罗非鱼碾碎提取物组、双蒸水组、空白对照组,通过暴露处理实验,检测沉底累积时间(time of bottom)、呆滞累积时间(time of freezing)两项指标,研究了28 dpf(days post fertilization,受精后天数)、35 dpf、42 dpf 3个不同发育时期幼鱼的报警反应。结果显示:28 dpf时,处理组与3个对照组相比,在沉底累积时间、呆滞累积时间两项指标上均无显著差异,这个时期处理组有2 ind斑马鱼出现"沉底",其中1 ind出现"呆滞";35 dpf时,处理组与3个对照组相比,在沉底累积时间上有显著差异(P0.05),在呆滞累积时间上无显著差异,这个时期有5 ind斑马鱼出现"沉底",其中1 ind出现"呆滞";42 dpf时,处理组与对照组相比,在沉底累积时间、呆滞累积时间两项指标均有显著差异(P0.05),这个时期有8 ind斑马鱼出现"沉底",且8 ind全部出现"呆滞",与此对应的是这个时期大部分个体出现明显的报警反应。研究表明,斑马鱼报警反应产生的发育阶段为35~42 dfp之间,结合已知的野外斑马鱼生活史,推测斑马鱼在特定的阶段产生报警反应可能与栖息地的迁移有关。     

Predicting use of habitat patches by spawning horseshoe crabs (Limulus polyphemus) along a complex coastline with field surveys and geospatial analyses

相似文献   

Distribution and habitat characteristics of three sympatric cetacean species in the coastal waters of Matang,Perak, Peninsular Malaysia

相似文献   

Factors influencing the abundance of three common nearshore fishes in south‐west Lake Michigan

Variation in the distribution and abundance of nearshore fishes is critical to understand food web processes and fishery management issues in Lake Michigan. This study characterised patterns in abundance of three common nearshore species, yellow perch Perca flavescens (Mitchell), round goby Neogobius melanostomus (Pallas) and alewife Alosa pseudoharengus (Wilson), in relation to spatio‐temporal, abiotic and biotic factors using gillnet sampling conducted across 5 years at multiple locations representing different substrates. Significant variations were observed in alewife and round goby catches between locations. A negative relationship between round goby and age‐0 yellow perch catch was observed, indicating potential competition between the two species. This study demonstrates that variability in nearshore fish communities can be driven by factors including substrate and interspecific interactions. Given the prominent role these species play in Lake Michigan's food web and thus their importance to fishery production, a thorough understanding of these factors is warranted.     

东南太平洋智利竹筴鱼栖息地指数的比较研究

根据2000~2007年度东南太平洋智利竹筴鱼的商业捕捞数据,结合海洋环境数据(SST,SSA,SSHG以及等温层深度),运用4种关联建模方法计算其栖息地指数,并使用Surffer 8.0软件绘制出HSI的空间分布图。通过2008年度的捕捞数据进行验证,结果表明4种模型的结果存在明显差异:采用算术平均法和几何平均法时,主要产量分布在0.6HSI0.9的区域;采用最大值法时,主要产量集中在0.8HSI1.0的区域;采用最小值法时,主要产量分布在0.3HSI0.6的区域。通过4种模型的验证结果比较,本文认为算术平均法和几何平均法能较好地反映东南太平洋智利竹筴鱼的中心渔场位置以及分布特征。     

Movements by adult cutthroat trout in a lotic system: implications for watershed-scale management

Abstract  Movements by adult cutthroat trout, Oncorhynchus clarkii (Richardson), were assessed from autumn to summer in the Salt River watershed, Wyoming-Idaho, USA by radio telemetry. Adult cutthroat trout were captured during September and October 2005 in the main stem of the Salt River, surgically implanted with radio transmitters, and tracked through to August 2006. Adult cutthroat trout were relatively sedentary and resided primarily in pools from October to March, but their movement rates increased during April. Higher movement rates were observed among tagged fish during May and early June. Among 43 fish residing in the Salt River during April 2006, 44% remained in the river, 37% moved into mountain tributaries and 19% moved into spring streams during the spawning season. Fish did not use segments of mountain tributaries or the upstream Salt River where fish passage was blocked by anthropogenic barriers or the channel was dewatered during summer. Almost all the fish that moved into spring streams used spring streams where pools and gravel–cobble riffles had been constructed by landowners. The results suggest that adult Snake River cutthroat move widely during May and early June to use spawning habitat in mountain tributaries and improved spring streams. Maintaining the ability of adult fish to move into mountain streams with spawning habitat, preserving spawning habitat in accessible mountain tributaries and removing barriers to upstream movements, and re-establishing summer stream flows in mountain tributaries affected by dams appear to be habitat management alternatives to preserve the Snake River cutthroat trout fishery in the Salt River.     

Spatial association between northern fur seal (Callorhinus ursinus) and potential prey distribution during the wintering period in the northern Sea of Japan

Elucidating the response of marine predators to oceanographic features helps in understanding their foraging strategies and the cause of their spatial overlap and interference with fishery activities. Northern fur seal is a highly pelagic species during the wintering period. In recent years, fur seals have consistently been found distributed near the coast of southwest Hokkaido, Japan. Because interference by fur seals with coastal fishery activities has become a serious concern, an understanding is sought as to why fur seals come ashore in this area. We conducted ship‐based observations and estimated fur seal density. To elucidate the spatial and seasonal association of fur seal distribution and ocean environments, we constructed statistical models to describe how potential prey distribution and oceanographic features influenced the fur seal spatial distribution during the wintering period. Fur seal distribution corresponded markedly to potential prey distribution, and they tended to aggregate along the narrow continental shelf that is the main geographic feature of this area, which is 2000 m deep and approximately 10 km from the coast. Walleye pollock [Gadus chαlcogrαmmα (Theragra chαlcogrαmmα)] and arabesque greenling (Pleurogrammus azonus), which are one of the main prey for fur seals, move to the shallow area to spawn on the continental shelf seasonally, so potential prey abundance could be higher in coastal areas than offshore. Moreover, the absence of a mesopelagic biotic community may be one of the main factors in the coastal distribution of the fur seal.     

我国渔业水域环境保护面临的问题与对策探讨

本文简要介绍了我国渔业水域环境监测体系的状况；分析了我国业水域环境保护面临的问题，如渔业水域环境损害严重，渔业水域的监督管理分散和渔业水域环境保护法规不完善；介绍了国外在渔业水域环境控制方面的经验，就如何解决我国渔业水域环境保护存在的问题，本文从建立集中的海洋环境监督,完善渔业水域环境保护的法律法规，健全渔业水域环境监测网络及加强水污染监测治理的科学技术研究等方面提出了一些建议。     

基于最大熵模型分析西南大西洋阿根廷滑柔鱼栖息地分布

根据2008—2010年中国鱿钓船在西南大西洋海域得到的生产数据及海洋环境数据(海表面温度,sea surface temperature,SST;海面高度sea surface height,SSH;叶绿素-a浓度,chlorophyll-a,chl.a),利用最大熵模型(Max Ent)分析捕捞主渔汛期间(1—4月)阿根廷滑柔鱼的潜在栖息地分布,同时与实际作业位置相比较,结合海洋环境因子分析不同年份分布差异的原因。模型运算结果显示:阿根廷滑柔鱼潜在分布区域的变化与实际作业位置变动基本一致;南北方向上,2008年和2009年的潜在分布区域较为广泛,而2010年的潜在分布区域较为狭窄,且主要分布在45°S以南的区域。Jackknife检验表明,SST是影响阿根廷滑柔鱼分布的首要环境因子,SST等温线分布可用来表征海流的强弱进而影响阿根廷滑柔鱼的分布,其中12°C等温线可以作为寻找渔场的一个指标。SSH等高线分布及其涡的变化也会影响到阿根廷滑柔鱼分布。chl.a只能间接地反映阿根廷滑柔鱼渔场的分布,不能很好地作为表征其分布的环境因子。研究表明,分析阿根廷滑柔鱼栖息地分布及其差异原因应主要观察SST和SSH的变化。     

南沙群岛重点岛礁潟湖微型浮游动物的群落结构与摄食

潟湖是岛礁生物多样性演变的重要环境场,在岛礁水生态系统的物质循环和能量流动中发挥重要作用,而微型浮游动物的生态功能研究是解析南沙群岛岛礁水域潟湖生态系统初级生产力组成、流向、能量流动效率的重要研究内容之一。实验通过对南沙群岛重点岛礁渚碧礁、美济礁与永暑礁潟湖表层水域中微型浮游动物与生态环境调查,研究了其群落结构及其与环境因子的关系,并通过稀释培养实验研究了微型浮游动物的摄食压力。结果显示,调查水域共发现微型浮游动物20种,总丰度的范围为320～1 460个/L,以无壳纤毛虫丰度最高。无壳纤毛虫在渚碧礁潟湖西部水域（ZB-1）丰度最高,砂壳纤毛虫峰值则出现在永暑礁潟湖中部水域（YS-3）,桡足类幼体丰度最大值出现在美济礁潟湖北部水域（MJ-2）。聚类分析结果显示,3个岛礁潟湖中部区域的微型浮游动物群落相似度较高,溶解氧是影响群落结构的最重要因素,特别是对MJ-3站位影响最为突出。摄食实验结果显示,3个岛礁潟湖水域浮游植物生长率为0.22～1.36 d^-1;微型浮游动物摄食率范围为0.22～0.60 d^-1,微型浮游动物每天约摄食浮游植物现存量的...