The Italian Alpine and Subalpine Trouts. Taxonomy, Evolution, and Conservation

Abstract

During the last 150 years, the trout-culture industry focused on enhancing trout populations by stocking, in response to the growing anglers’ demand and the habitat degradation associated to the rapid urbanization and hydropower development. The industrialized north of Italy, home to the Italian Alpine and subalpine trout populations, is the source of most of the revenues of the national trout-culture industry. Its rapid growth and the massive introduction of non-native interfertile trouts eroded the genetic diversity of native lineages, leading to harsh confrontations between scientists, institutions, and sportfishing associations. We review here the state of art of the taxonomy and distribution of the northern Italian native trouts, presenting both scientific results and historical documentation. We think the only native trouts in this region are Salmo marmoratus, widespread in this region, plus small and fragmented populations of S. ghigii, present only in the Southwestern Alps. We strongly recommend the interruption of stocking of domesticated interfertile non-native trouts in this area, and recommend the adoption of Evolutionary Significant Units for salmonid fishery management. We further propose future research directions for a sustainable approach to the conservation and ecosystem management of the fishery resources and inland waters of northern Italy.

The role of semen cryobanks for protecting endangered native salmonids: Advantages and perspectives as outlined by the LIFE Nat.Sal.Mo. project on Mediterranean brown trout (Molise region – Italy)

“…Salmo macrostigma (Querci et al, 2013;Lorenzoni et al, 2019;Splendiani et al, 2019;Carosi et al, 2020). However, according to recent genetic findings the Italian peninsular Mediterranean brown trout belongs to a different taxon known as S. ghigii, therefore limiting the name S. cettii to Sicilian trout (Lorenzoni et al, 2019;D'Agaro et al, 2022;Polgar et al, 2022). Although, we agree with this recent evidence, we still use the name S. cettii, because Mediterranean brown trout populations are still protected by the Habitat Directive and subsequent conservation status updates under this taxon.…”