Computation of confidence intervals for the size‐frequency (Hynes) method of estimating secondary production1

摘要: An estimator of variance is described for production values calculated by the size-frequency (Hynes) method. The number sampling dates identified as having an important influence on estimate. A geometric mean proposed to estimate average weight individuals when lost between size classes. In example calculation, Ephemerella dorothea (Ephemeroptera) from North Branch Creek, Minnesota, had annual value 8.5 g·m−2 wet and approximate 95% confidence interval 7.0–10.0. Similar calculations Baetis sp. same river yielded 4.7 with a 3.6–5.8. Significant differences in thus exist these mayflies.