Janus Pannonius Múzeum Évkönyve 28 (1983) (Pécs, 1984)

Természettudományok - Uherkovich, Ákos: Lepidoptera on birch and alder in South and West Transdanubia, Hungary

46 ÁKOS UHERKOVICH „Belső-Somogy", Juniper Woodland of Barcs 1974, June 5 June 18 1977, June 7 1979, May 19 May 24 1980, June 2 June 3 June 9 June 23 1981, June 1 55 specimens 14.6 p. с d* 27 specimens 6.7 p. с d 63 specimens 12.2 p. с sd 45 specimens 5.0 p. с sd 41 specimens 6.7 p. с sd 148 specimens 48.1 p. с d 37 specimens 13.6 p. с d 84 specimens 15.8 p. с d 61 specimens 12.0 p. с d 310 specimens 25.0 p. с d 1.7Ü1, j une j. JL\J spcuuiciis .Í4J.U y. l~. u Dráva Fiatland, Kisdobsza, forest 1977, May 12 80 specimens 10.8 p. с d 215 specimens 14.7 p. с d 141 specimens 22.9 p. с d Ivarhely, forest 38 specimens 4.4 p. c. sd 80 specimens 1981, May 21 1982, June 6 ±i± specimens z. Dráva Flatland, Somogyudvarhely, forest 1980, June 10 38 specimens Szőce, valley (W-Hungary) 1983, June 9 57 specimens 8.1 p. с d d = dominant, sd = subdominant Tethea duplaris L. became dominant species only once (Szőce, valley, W-Hungary July 28, 1983: 95 specimens, 8.1 p. c). All of these results were collected from lampings of author's own. The light traps cannot capture these species (mainly Hydriomena caerülata F.) according to their actual quantity because of their curious flight: the moths sit down right by the lamp and they remain there. They do not circle around the lamp or knock against the parts of the trap either. Therefore they do not fall into collecting jars of traps - and they are represented in our material to a lesser degree than their true massoccurence is in nature. The behaviour of some geometrid moths can be similar towards traps, therefore, their representation is unduely low in some trap-materials. The majority of the rest of the species has never reached dominant or subdominant level, but they can be often captured. A few of them are very rare, e. g. Leucodonta bicoloria Den. et Schiff., Calocalpe undulata L., Plemyria rubiginata Den. et Schiff, and Hydraelia sylvata Den. et Schiff. The species living on birch and/or alder do not cause damage in our forests because of their comparatively small amount. Therefore their distribution and occurence is interesting only from an ecological and zoogeographical point of view. When the total map of birch-feeding species was compiled, a great amount of similarity could be noted between their distribution and the annual total precipitation. The maximum of rainfall coincides with the highest number of these species on the area of Southwestern Transdanubia: from Őrség (County Vas) to Dráva Flatland of County Baranya (Sellye-Gilvánfa environments). On this area the precipitation surpasses the 800 mm level yearly (and, even, it reaches the 1000 mm level in some points of the western boundary zone). On these parts there are wet-type forests: various oak-stands (hornbeam-oak-stands, mainly), alder-groves, elm-ash-groves, various types of moor-forests (alder-moors, mostly) and beeches en the hills and in valleys, and sometimes, on lowlands (Fig. 26). The distribution of monophagous alder-feeding species shows no such a clear relation with precipitation. As I have pointed out, these species can Fig. 25. The number ot birch-eating species on South and West Transdanubia. 25. ábra. A nyírevő fajok száma a Dél- és NyugatDunántúlon. Fig. 26. The number ot amphihagous as well as monophagous alder-eating species, further 2 polyphagous species preterrig alder, on South and West Transdanubia. 26. ábra. A monotág égerevők, az amtifág fajok és 2, égeren is élő poliiág faj együttes előfordulási fajszáma a Dél- és Nyugat-Dunántúlon.