Status of Austropotamobius Pallipes Complex in the Watercourses of the Alessandria Province (N-W Italy)

Abstract

Information was gathered on the distribution of white-clawed crayfish Austropotamobius pallipes complex in the watercourses of the Alessandria province (NW Italy), on the biological and ecological preferences of the species, and on the features of the biotopes in which it is found. A total of 409 sites on 361 watercourses connected to the main sub-basins of the Po River were analysed, with data gathered during the field research phase, conducted for three consecutive summers from 2002 through 2004. Thirteen percent of the sites investigated were found to currently house crayfish populations. The persistence in time of superficial water and natural morphology of the watercourse were found to be the chief requirements for the presence of crayfish. Data on land use, human density and other factors which potentially limit the survival of crayfish populations were also analysed. Key-words:Austropotamobius pallipes complex, freshwater crayfish, bio-ecological characteristics. STATUT DU COMPLEXE D'ESPACE D'AUSTROPOTAMOBIUS PALLIPES DANS LES COURS D'EAU DE LA PROVINCE D'ALESSANDRIA (ITALIE NORD-OCCIDENTALE) RÉSUMÉLe projet de recherche a prévu la récolte d'informations sur la répartition du complexe d'espèce Austropotamobius pallipes dans les réseaux hydrographiques de la province d'Alessandria (Italie nord-occidental), sur les caractères bio-écologiques de l'espèce et sur les caractéristiques des milieux où elle a été trouvée. Les prospections de terrain ont été faites durant trois étés consécutifs de la période 2002-2004 et ont permis d'analyser 409 sites sur 361 cours d'eau, appartenant aux principaux sous-bassins du fleuve Pô. Des populations d'écrevisses n'ont été trouvées que dans 13 % des sites prospectés. La persistance temporelle des débits hydriques superficiels et la morphologie naturelle constituent la condition essentielle pour la présence des écrevisses. En outre, les données

Estimating age composition in Alpine native populations of Austropotamobius pallipes complex

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Change does not happen overnight: a case study on stream macroinvertebrates

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The use of formaldehyde for the disinfection of maternally incubated eggs of noble crayfish (Astacus astacus)

“…In fact, the use of separate tanks for disinfection reduces the quantity of treated water to a great extent (tank volume of 4 l) and facilitates the separate management of treated water, thus avoiding its release into natural water bodies. In Italy, a great deal of attention has been paid to the reintroduction of white-clawed crayfish (Nardi et al 2005) and several LIFE projects, funded by the EU, are focused on this species (e.g., http://www. lifecrainat.eu/en/).…”