Density-Dependent Growth in Juvenile Sockeye Salmon (Oncorhynchus Nerka)
Density-Dependent Growth in Juvenile Sockeye Salmon (Oncorhynchus Nerka)
复制标题
红鲑幼鱼 (Oncorhynchus Nerka) 的密度依赖性生长
DOI：
--
复制
发表时间：
2011
期刊：
影响因子：
--
通讯作者：
É. Demers
中科院分区：
文献类型：
--
作者：
K. Hyatt;D. Mcqueen;D. P. Rankin;É. Demers
从不列颠哥伦比亚省4个沿海红鲑鱼苗圃湖泊收集的77年湖泊数据表明，只有在异常高的鱼苗密度下，才有可能出现依赖于密度的生长减少。在大中央湖（n=33年）和斯普拉特湖（n=30年），幼鱼体重与夏季平均鱼苗密度在760 ~ 3800尾/ h -1之间没有相关性。然而，在鱼苗密度异常高的两年中（1983年=5183公顷-1,1996年=4801公顷-1），幼鱼体重处于记录的最低水平。在wss湖和Vernon湖（n=14湖年），秋季鱼苗质量与浮游动物生物量呈显著的自下而上关系，而12月鱼苗质量与平均鱼苗密度（范围331 ~ 1361 ha -1）之间无显著的自上而下关系，鱼苗密度与平均浮游动物生物量之间也不存在显著的自上而下关系。浮游动物产量与鱼苗生物量的比较表明，浮游动物产量最高的弗农湖的承载能力为12700鱼苗ha -1，浮游动物产量最低的斯普罗特湖的承载能力为5200鱼苗ha -1。我们得出结论，在不列颠哥伦比亚省沿海湖泊（即500-4000公顷-1）通常观察到的鱼苗密度范围内，不会导致猎物生物量或鱼苗生长率的密度依赖减少。进一步的研究是必要的。
Data gathered over 77 lake-years from 4 coastal British Columbia sockeye salmon nursery lakes suggest that density-dependent growth reductions are only possible at exceptionally high fry densities. In Great Central Lake (n=33 years) and Sproat Lakes (n=30 years) there was no relationship between smolt weight and mean summer fry densities ranging from 760-3800 fry ha -1 . However, in two years when Sproat Lake fry densities were unusually high (1983=5183 ha -1 , 1996=4801 ha -1 ) smolt weights were among the lowest recorded. In Woss and Vernon lakes (n=14 lake-years), there were significant bottom-up relationships between fall-fry weights and zooplankton biomass, but no relationships between December-fry weights and average fry densities (range 331-1361 ha -1 ), nor were there significant top-down relationships between fry densities and average zooplankton biomass. Comparisons of zooplankton production with bioenergetic-based fry consumption, suggested that the carrying capacity for Vernon Lake which had the highest rate of zooplankton production, was 12,700 fry ha -1 , and for Sproat Lake which had the lowest zooplankton production, was 5200 fry ha -1 . We conclude that fry densities in the range commonly observed for British Columbia coastal lakes (i.e. 500-4000 ha -1 ) cannot cause density-dependent reductions in prey biomass or fry growth rates. Further research is necessary.