Animal xenodiversity in Italian inland waters: distribution, modes of arrival, and pathways

Abstract

The paper provides a list of the non-indigenous animal species occurring today in Italian inland waters. Xenodiversity was found to amount to 112 species (64 invertebrates and 48 vertebrates), which contribute for about 2% to the inland-water fauna in Italy. Northern and central regions are most affected, and Asia, North America, and the rest of Europe are the main donor continents. The large majority of non-indigenous species entered Italy as a direct or indirect effect of human intervention. A difference between invertebrates and vertebrates was found for their mode of arrival (unintentional for invertebrates and intentional for vertebrates). Accidental transport, in association with both fish (for aquaculture or stock enhancement) and crops, has been the main vector of invertebrate introductions, whereas vertebrates were mostly released for stocking purposes. Overall stock enhancement (47.92%) and culture (37.5%) prevailed over the other pathways. Seventeen and 7 species of our list are included among the 100 worst invasive species of Europe (DAISIE) and of the world (IUCN), respectively. For some (but not all) non-indigenous species recorded in Italy the multilevel impact exerted on the recipient communities and ecosystems is known, even if rarely quantified, but knowledge on their chronic impact is still missing. Additional research is needed to provide criteria for prioritizing intervention against well established invaders and identify which new potential invader should be targeted as "unwanted"

Lifting the curtain on the freshwater mussel diversity of the Italian Peninsula and Croatian Adriatic coast

“…This rather striking difference in haplotype diversity between sympatric A. anatina clades could indicate that the two European A. anatina haplotypes actually represent introductions into these Italian lakes, possibly in the larval stage through fish host stocking. This hypothesis is supported by the fact that Lake Trasimeno and Lake Maggiore are rich in non-native fish species (Gherardi et al 2008;Volta and Jepsen 2008;Boggero et al 2016), originating mainly from Central Europe. Our observation that the Ebro?Italy mtDNA clade contains higher genetic diversity than the European clade, despite occupying a more restricted geographical area, supports the idea that Italy served as an important refugium during the Pleistocene glaciations, as has been documented for other taxa (e.g.…”

Can the introduction of Xenopus laevis affect native amphibian populations? Reduction of reproductive occurrence in presence of the invasive species

“…Many human activities, such as agriculture, aquaculture, recreation and transportation, are the cause of intentional or accidental spread of species away from their natural ranges of distribution (Gherardi et al 2008). Although most new species fail to establish viable populations, those that persist can threaten native biodiversity and ecosystem functionality, and may have detrimental effects on human health as well as economic impacts (Kolar and Lodge 2001).…”

The recent invasion of Rutilus rutilus (L.) (Pisces: Cyprinidae) in a large South- Alpine lake: Lago Maggiore

“…After the 1950s the presence of exotic species in Italy increased rapidly and the adverse effect of these invaders is now a major problem for the local fish fauna (Bianco 1998;Bianco & Ketmeier 2001;Gherardi et al 2008).…”