Overwintering larvae of the Alpine newt Ichthyosaura alpestris in the Gorce Mts

Wczesną wiosną przez trzy kolejne lata (2009–2011) obserwowano w niewielkim oczku wodnym w Gorcach larwy traszki górskiej Ichthyosaura alpestris (Laurenti, 1768) w zaawansowanych stadiach rozwoju. Wskazuje to jednoznacznie na zimowanie larw traszki pod lodem i jest pierwszym bezpośrednim potwierdzeniem tego nietypowego zjawiska w Gorcach. Obserwacje te dostarczają dowodów, że nawet niewielkie zbiorniki wodne mogą być ważnym miejscem życia i rozrodu chronionych gatunków płazów

Overwintering larvae of the Alpine newt Ichthyosaura alpestris were observed in a small pond in the Gorce Mts (Poland, 49°30′N, 20°08′E, elevation 900 m a.s.l.) in early spring of 2009–2011. Typically, larvae of this newt species hatch from eggs in spring or early summer; after 3–4 months of development, they undergo metamorphosis and leave the aquatic environment. In certain conditions, however, especially in lower temperatures, the larvae may be unable to achieve a sufficient stage of development to leave the ponds before winter. In Poland, the presence of non-metamorphosed larvae of the Alpine newt were reported in several montane water reservoirs in late autumn and early spring (Świerad 1988, 2003), but there was no direct evidence of this phenomenon in the Gorce Mountains. Observations presented in this paper prove that overwintering of Alpine newt larvae occurs also in this area and this unusual phenomenon may regularly take place in the aforementioned pond. Moreover, seemingly insignificant, small water reservoirs (about 1 m in diameter; less than 1 m of depth) may be a valuable habitat for protected amphibian species