Critical threshold size for overwintering sandeels (Ammodytes marinus)
Critical threshold size for overwintering sandeels (Ammodytes marinus)
复制标题
越冬砂鳗（Ammodytes marinus）的临界尺寸
DOI：
10.1007/s00227-011-1774-8
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发表时间：
2011
期刊：
影响因子：
2.4
通讯作者：
J. Steffensen
中科院分区：
文献类型：
--
作者：
M. Deurs;Martin Hartvig;J. Steffensen
几种生态和商业上重要的鱼类在最少的摄食活动和较低的捕食风险的状态下过冬。为了实现这种越冬行为，在冬季之前会产生能量储备，以支持冬季新陈代谢。鱼的维持新陈代谢随身体大小而变化，并随温度升高而增加，这两个因素共同决定了被动越冬的临界阈值大小，低于该阈值的生物不太可能在不取食的情况下生存。这是因为新陈代谢的能量成本超过了最大能量储备。在目前的研究中，我们从生物能量学模型中估计了越冬的能量成本。在5.3至18.3°C的温度范围内，使用基于呼吸测量的测量埋藏的托比亚纳(与海洋亚种的近亲)的标准代谢率来对模型进行参数化，并通过两个独立的长期越冬实验进行验证。最大可获得的能源储量是根据公布的北海海马鱼数据估计的。以长度(Lth)计算，北海黑线对虾的临界阈值大小估计为9.5厘米。然后我们研究了两个普遍的预测：(1)小于lth的鱼类表现出冬季摄食活动，(2)陆栖物种成熟时的大小大于lth，以确保有足够的能量储备来满足被动越冬和繁殖投资的代谢成本。这两个预测都被发现与12月和2月关于成熟时的体型和总能量的数据一致。
Several ecologically and commercially important fish species spend the winter in a state of minimum feeding activity and at lower risk of predation. To enable this overwintering behaviour, energetic reserves are generated prior to winter to support winter metabolism. Maintenance metabolism in fish scales with body size and increases with temperature, and the two factors together determine a critical threshold size for passive overwintering below which the organism is unlikely to survive without feeding. This is because the energetic cost of metabolism exceeds maximum energy reserves. In the present study, we estimated the energetic cost of overwintering from a bioenergetic model. The model was parameterised using respirometry-based measurements of standard metabolic rate in buried A. tobianus (a close relative to A. marinus) at temperatures from 5.3 to 18.3°C and validated with two independent long-term overwintering experiments. Maximum attainable energy reserves were estimated from published data on A. marinus in the North Sea. The critical threshold size in terms of length (Lth) for A. marinus in the North Sea was estimated to be 9.5 cm. We then investigated two general predictions: (1) Fish smaller than Lth display winter feeding activity, and (2) size at maturation of iteroparous species is larger than Lth to ensure sufficient energy reserves to accommodate both the metabolic cost of passive overwintering and reproductive investments. Both predictions were found to be consistent with data on size at maturation and total body energy in December and February.