A Method for Quantifying of Aquatic Insects Emergence on the Basis of the Drift Samples

Based on the well-known fact of the short-term metamorphosis of amphibiotic insects when emerging out directly from the water bodies' surface, the author proposes a calculation method for such departure rate estimating from lotic systems based on drift collections. The calculation is made taking into account the area of the bottom site (1 m) adjacent to the observation section. In passing, the problem of the discrepancy between the efforts spent on data collecting and the meager volume of data obtained is considered, which is especially relevant when working on small watercourses, where the emergence of some species is scattered and low-intensive.