Native and alien Decapoda species in Hungary: Distribution, status, conservation importance

Abstract

Three native (Astacus astacus, Astacus leptodactylus, Austropotamobius torrentium) and three alien (Orconectes limosus, Pacifastacus leniusculus, Eriocheir sinensis) Decapoda species have been found in Hungary so far. A. astacus is the most widespread Decapoda species in Hungary. A leptodactylus might be considered as the least studied. The distribution of A torrentium in Hungary is restricted to mountain streams with occasional data on its presence in the adjacent section of the River Danube. The indigenous species A torrentium and, especially A astacus, are declining while A. leptodactylus seems to have stable populations. The detection of alien species accelerated at the turn of the century: O. limosus was found at new sites, P. leniusculus was first recorded in the Gyöngyös-stream near the Austrian border in 2000, E. sinensis in the main arm of the Danube at Budapest in November 2003. As there is a lack of information even on the commonest species, conservation-oriented mapping is necessary to follow the distribution changes of Decapoda in Hungary.