Immigration, settlement, and density-dependent mortality of a larval and early postlarval 0-group plaice (Pleuronectes platessa) population in the western Wadden Sea
Immigration, settlement, and density-dependent mortality of a larval and early postlarval 0-group plaice (Pleuronectes platessa) population in the western Wadden Sea
复制标题
瓦登海西部幼体和幼体早期 0 组鲽 (Pleuronectesplatessa) 种群的迁徙、定居和密度依赖性死亡率
DOI：
10.3354/meps029223
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发表时间：
1986
影响因子：
2.5
通讯作者：
H. van der Veer
中科院分区：
文献类型：
--
作者：
H. van der Veer
根据幼体迁徙、随后的定居和底层密度变化的信息，研究了瓦登海西部临时隔离的0组鳕鱼种群中的死亡因素。从2月底到5月初，幼虫每年都会进入瓦登海西部。在幼虫数量丰富的年份，从3月到4月，主要幼虫的到达似乎有些延迟。结果表明，6月1日落户种群的年际平均长度与密度呈负相关。在幼虫落户期间和落户后不久，观察到约35 mm的密度依赖性死亡，瞬时死亡率高达0.06d-L。论证了，虽然沿海地区存在中上层捕食者(几种腔肠动物)，但主要的依赖于洞穴的死亡过程发生在底层阶段。幼虫的数据进一步表明，在生命的早期，在公海的浮游阶段，就建立了年级强度的水平。在瓦登海观察到的密度依赖性死亡率将公海卵和仔鱼阶段产生的年级强度的年际变化从幼虫迁徙时的62%的变异系数降低到6月份定居后的30%。
Mortality factors operating in a temporarily isolated 0-group plaice population in the western Wadden Sea have been examined from information on larval immigration, subsequent settlement and changes in demersal densities. Larvae entered the western Wadden Sea every year from the end of February to the beginning of May. In years of strong larval abundance the main perlod of arrival seemed somewhat delayed from March to April. As a result, between-years mean length and density of the settled population showed an inverse relation on June 1. Density-dependent mortality was observed among plaice up to about 35 mm, with instantaneous mortality rates ranging up to 0.06 d-l during and shortly after settling of the larvae. Arguments are given that, although in the coastal zone pelagic predators are present (several coelenterate species), the main dens~ty-dependent mortality processes operate in the demersal phase. The larval data further showed that level of yearclass strength was established early in life, during the planktonic stage in the open sea. Observed density-dependent mortality in the Wadden Sea reduced the between-year variation in year-class strength generated in the open sea egg and larval stages from a coefficient of variation of 62 % during larval immigration to 30 % after settling in June.