Seasonal variability in the abundance of Arctic charr (Salvelinus alpinus (L.)) recorded using hydroacoustics in Windermere, UK and its implications for survey design
Seasonal variability in the abundance of Arctic charr (Salvelinus alpinus (L.)) recorded using hydroacoustics in Windermere, UK and its implications for survey design
复制标题
使用英国温德米尔水声学记录的北极红点鲑 (Salvelinus alpinus (L.)) 丰度的季节变化及其对调查设计的影响
DOI：
--
复制
发表时间：
2007
期刊：
影响因子：
--
通讯作者：
J. B. James
中科院分区：
文献类型：
--
作者：
I. Winfield;J. Fletcher;J. B. James
水声测量是评估北极红点鲑（Salvelinus alpinus（L.）在湖泊中，由于新的环境立法，对湖泊的需求正在增加。因此，现在的调查要求是，必须以符合科学有效性的最小努力进行评估。一个主要的复杂因素是丰度的季节性变化，测量人员试图通过确定多少有些武断的季节性取样窗口来处理这一问题。更客观的窗口的定义进行了分析，在英国温德米尔的北极红点鲑的季节性丰度的变化，记录使用白天和夜间水声调查每月的间隔从1991年至2001年。本研究揭示了两个不受显著内部季节性影响的夜间调查替代抽样窗口，即，十二月到九月和九月到十二月。还发现，与夜间调查相比，白天调查对丰度作出了有用的估计，尽管估计值较低。
Hydroacoustic surveys are an important tool for assessing the abundance of Arctic charr (Salvelinus alpinus (L.)) in lakes, the requirement for which is increasing because of new environmental legislation. Consequently, survey demand is now such that assessments must be undertaken with the minimum of effort compatible with scientific validity. One major complication is seasonal variability in abundance, with which surveyors have attempted to deal by defining somewhat arbitrary seasonal sampling windows. The definition of more objective windows was pursued by analysing variations in the seasonal abundance of Arctic charr in Windermere, UK, recorded using day and night hydroacoustic surveys at monthly intervals from 1991 to 2001. Two alternative sampling windows for night surveys free of significant internal seasonal effects were revealed, i.e., December to September and September to December. It was also found that day surveys gave a useful, although lower, estimate of abundance as compared with night surveys.