Mass mortality of Strongylocentrotus droebachiensis (Echinodermata: Echinoidea) off Nova Scotia, Canada
Mass mortality of Strongylocentrotus droebachiensis (Echinodermata: Echinoidea) off Nova Scotia, Canada
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加拿大新斯科舍省附近的Strongylocentrotus droebachiensis（棘皮动物门：Echinoidea）大规模死亡
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发表时间：
1984
期刊：
影响因子：
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通讯作者：
R. Stephenson
中科院分区：
文献类型：
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作者：
R. Scheibling;R. Stephenson
1982年，在加拿大新斯科舍省西南海岸的鹰头（Eagle Head），在一个以棘球绦虫为主的贫瘠土地上，监测到由于疾病造成的Droebachiensis球海胆大量死亡。死亡率为70%，在浅（3米）近岸地区，导致海胆生物量的损失2 042克鲜重m-2，和6%，在较深的（7米，10米）近海地区。近海地区海胆密度、大小和营养状况（性腺指数）最高。幼鱼（直径<15 mm）的存活率高于成年鱼，导致在近岸区域形成双峰尺寸分布。死亡开始于10月初左右，接近海水温度年周期的峰值（15°C），并在12月初（海水温度17 °C）时停止，当时病态的棘球蚴似乎恢复了。在实验室实验中，S.暴露于病态同种的droebachiensis随着温度的降低（20°至8°C）呈指数增加。60天后，在20° C和16°C下没有存活，在12°C下有20%存活，在8°C下有100%存活;这表明病原体可能传播的温度下限（12° C至8°C）。在16°C下实验的实验室病态棘球蚴和12月初在近岸地区收集的恢复棘球蚴，在<=8°C下分别显示100%和85%的存活率，在16°C下分别显示0%和15%的存活率，30天后。发病时间没有显着影响的营养状况，是类似的青少年和成人棘球蚴。发病的时间是更大的棘球蚴暴露于一个或三个病态的个人连续，或7个病态的个人1小时，相对于较高的曝光水平（高达7个病态的个人连续）。最近的大规模死亡在S。droebachiensis发生在创纪录的高海面温度的年份。死亡的程度与温度高于下限的幅度和持续时间有关。
A mass mortality of Strongylocentrotus droebachiensis, attributed to disease, was monitored in an echinoiddominated barren ground at Eagle Head on the south-western coast of Nova Scotia, Canada, in 1982. Mortality was 70% in a shallow (3 m) nearshore area, resulting in a loss of echinoid biomass of 2 042 g fresh weight m-2, and 6% in deeper (7 m, 10 m) offshore areas. Echinoid density, size and nutritional condition (gonad index) were highest in the nearshore area. Survivorship was higher in juveniles (<15 mm diameter) than in adults resulting in the formation of a bimodal size distribution in the nearshore area. Mortality began around early October, near the peak of the annual cycle of seawater temperature (∼15°C), and was arrested by early December (seawater temperature ∼7°C) when morbid echinoids appeared to recover. In laboratory experiments, time to morbidity of S. droebachiensis exposed to morbid conspecifics increased exponentially with decreasing temperature (20° to 8°C). There was no survival at 20° and 16°C, 20% survival at 12°C and 100% survival at 8°C after 60 d; suggesting a lower temperature limit (between 12° and 8°C) for possible transmission of a pathogenic agent. Morbid laboratory echinoids from experiments at 16°C, and recovering echinoids collected in the nearshore area in early December, showed 100 and 85% survival respectively at <=8°C, and 0 and 15% survival respectively at 16°C, after 30 d. Time to morbidity was not affected significantly by nutritional condition and was similar for juvenile and adult echinoids. Time to morbidity was greater in echinoids exposed to one or three morbid individuals continuously, or seven morbid individuals for 1 h, relative to higher levels of exposure (up to seven morbid individuals continuously). Recent mass mortalities in S. droebachiensis have occurred in years of record high sea surface temperatures. The extent of mortality is correlated with the magnitude and duration of temperatures above a lower limit.