Hidrológiai Közlöny 2004 (84. évfolyam)
5-6. szám - XLV. Hidrobilógus Napok „Vizeink hosszú idejű változásai” Tihany, 2003. október 1–3.
135 cializáltabb a Diptera imágók fogyasztása és a kannibalizmus során volt. Az irodalmi adatokkal összevetve a Hévízi-tóban élő populáció étrendjén szokatlanul magas a növényi táplálék aránya (Arthinglon 1989, Cabral és mtársai 1998, Ar thington és Marshall 1999, Garcia-Berthou 1999). Ez az állati eredetű táplálék szűkösségét jelezheti. A táplálékban csípőszúnyog lárvát nem találtunk, amely összhangban van azon feltételezésekkel, miszerint ilyen lárvák a tóban nem is élnek (Ponyi 1995). így, a betelepítés indokai sem világosak. Ugyanakkor, tekintettel a populáció nagy nyári egyedsürűségére és a vízi gerinctelen-fauna kis biomasszájára, a szúnyogirtó fogasponty igen jelentős predációs nyomást jelenthet a Hévízi-tó egyedi gerinctelen faunájára. Köszönetnyilvánítás Jelen kutatások a Szent András Állami Reumatológiai és Rehabilitációs Kórház (Hévízfürdő) támogatásával készültek. Irodalom Amundsen P. A., Gabler H. M. d Staldvik F. J. (1996). A new approach to graphical analysis of feeding strategy from stomach contents data: modification of the Costello (1990) method. J. Fish Biol. 48. 607-614. Arthinglon A. H. (1989). Diet of Gambusia affinis holbrooki, Xiphophorus helleri , X. maculalus and Poecilia reticulata (Pisces: Poeciliidae) in streams of southeastern Queensland, Australia. Asian Fish. Sei. 2: 193-212. Arthington A. H. & Marshall C. J. (1999). Diet of the exotic mosquitofish Gambusia holbrooki in an Australian lake and potential for competition with indigenous fish species. Asian Fish. Sei. 12: 1-16. Bíró P. (1976). A Hévizi-tó halfaunájáról. Halászat 22: 186-188. Cabral J. A.. Mieiro C. L. & Marques J. C. (1998). Environmental and biological factors influence the relationship between a predator fish, Gambusia holbrooki, and its main prey in rice fields of the Lower Mondego River Valley (Portugal). Hydrobiologia 382: 41-51. Courlenay W. R. á Meffe G. K. (1989). Small fishes in strange places: a review of introduced poeciliids. In: Meffe G. K. & Snelson F. F. (eds), Ecology and evolution of livebearing fishes (Poeciliidae). Prentice Hall, New Jersey: 319-331. Englund R E. (1999). The impacts of introduced Poeciliid fish and Odonata on the endemic Megalagrion (Odonata) damselflies of Oahu Island, Hawaii. J. Insect Conserv. 3: 225-243. Fernández-Delgado C. (1989). Life-history patterns of the mosquitofish, Gambusia affinis, in the estuary of the Guadalquivir river of south-west Spain. Freshwal. Biol. 22: 395-404. Fernández-Delgado C. & Rossomanno S. (1997). Reproductive biology of the mosquitofish in a permanent natural lagoon in south-west Spain: two tactics for one species. J. Fish Biol. 51: 80-92 Garcia-Berthou E. (1999). Food of introduced mosquitofish: ontogenetic diet shift and prey selection. J. Fish Biol. 55: 135-147. Goodsell J. A. & Kals L. B. (1999). Effect of introduced mosquitofish on pacific treefrogs and the role of alternative prey. Conserv Biol. 13:921-924. Hyslop E. J. (1980). Stomach content analysis - a review of methods and their application. J. Fish Biol. 17: 411-429. Komak S. & Crossland M. R. (2000). An assessment of the introduced mosquitofish (Gambusia affinis holbrooki ) as a predator of eggs, hatchlings and tadpoles of native and non-native anurans. WildI. Res. 27: 185-189. Krumholz L. A. (1948). Reproduction in the western mosquito fish Gambusia affinis and its use in mosquito control. Ecol. Monogr. 1 8: 1-43. Meffe G. K. (1991). Life history changcs in eastern mosquitofish (Gambusia holbrooki) induced by thermal elevation. Can. J. Fish, aqual. Sei. 48: 60-66. Meffe G. K. (1992). Plasticity of life-history characters in eastern mosquitofish (Gambusia holbrooki. Poeciliidae) in response to thermal stress. Copeia 1992: 94-102. Meffe G. K., Weeks S. C„ Mulvey M.& Kandi K. L. (1995). Genetic differences in thermal tolerance of eastern mosquitofish (Gambusia holbrooki ; Poeciliidae) from ambient and thermal ponds. Can. J. Fish, aquat. Sei. 52: 2704-2711. Milton D. A. & Arthinglon A. H. (1983). Reproductive biology of Gambusia affinis holbrooki Baird and Girard, Xiphophorus helleri (Günther) and X. maculalus (Heckel) (Pisces; Poeciliidae) in Queensland, Australia. J. Fish Biol. 23: 23-41. Ponyi J. (1995). A Hévízi-tó állatvilága. Hidr. Táj. 1995 April: 21-23. Vargas M. J. & de Sosloa A. (1996). Life hutory of Gambusia holbrooki (Pisces, Poeciliidae) in the Ebro Delta (NE Iberian Peninsula). Hydrobiologia 341: 215-224. Abstract: Keywords: Biological characteristics of the eastern mosquitofish (Gambusia holbrooki) in Lake Hévíz András Specziár Lake Hévíz should be considered as an extreme habitat for the eastern mosquitofish as it lies far outside of the native geographic and climate range of this fish and has a special thermal water with very high water temperature in summer Aim of this work was to analyze population structure, life history pattern and feeding ecology of eastern mosquitofish in Lake Hévíz, with special attention to the effects of the extreme thermal habitat. Gambusia holbrooki, exotic species, fecundity, reproduction season, diet, Lake Hévíz. Klossy Irén alkotása