Gestion forestière et écologie des populations de chouette de Tengmalm (Aegolius funereus) dans l’est de la France

Abstract

A breeding population census of the Tengmalm’s Owl was carried out, from 1984 to 1986, in six different areas of Bourgogne, Jura and Haut-Vercors, France. The total area surveyed was 100 km2. The largest number of breeding territories found in 1984 was 71. Breeding densities averaged 0.6 pair per km2, with a maximum of 1.3 pair per km2. Altogether, 47 nests were found by systematically checking tree holes and nest boxes. The Tengmalm’s Owl population studied displayed wide population fluctuations in relation to rodent population cycles (Clethrionomys glareolus and Apodemus sp.). Tengmalm’s Owl very often uses Black Woodpecker’s nests to breed ; such nest sites are particularly numerous in large Beech trees, within old mature forest. To keep patches of unlogged mature forest (1-2 ha), at a density of one patch per 100 ha, would certainly help preserving a self-sustaining population of Tengmalm’s Owl in our study area.