A study upon the total abundance of two whitefaces, Leucorrhinia caudalis and Leucorrhinia pectoralis was performed at the beginning of June 2008 in the nature reser- ve “Zdręczno Lake”, Tuchola Forest. The abundance estimation was based upon the number of exuviae collected within the re- serve, among the reed and shore vegetation, also in some distance from the shore. Alto- gether 76 samples were gathered, each com- posed of exuviae collected from the area of 1m2. In total 101 exuviae of L. caudalis (mean density: 1.33 ind/m2, density range: 0–7 ind/m2, SD=1.32) and 176 exuviae of L. pectoralis (mean density: 2.32 ind/m2, density range: 0–7 ind/m2, SD=1.68) were found. Based on aerial photographs (Phot. 1) the total area of habitat available for whi- teface larvae in Zdręczno Lake was estima- ted to be from 12 179 m2 (1.2 ha) to 65 969 m2 (6.6 ha). Concluding, the total population abundance in the reserve was calculated as 16 198–97 739 individuals for L. caudalis and 28 255–153 048 individuals for L. pectoralis
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.