Frederick Ielli This article Federico Ielli affronta l'importante problema della tutela del fenotipo italiano del luccio in un ottica conservazionistica, in riferimento ai recenti studi della Dott.ssa Livia Lucentini ricercatrice dell'Università di Perugia. La necessità di individuare alcune linee guida per la conservazione delle popolazioni di luccio italiche appare oggi fondamentale anche se non esente da difficoltà.
Introduzione
Il luccio (Esox lucius L.,) è specie ad ampia distribuzione europea, asiatica e Nord americana. In Italia la specie è nativa nelle regioni settentrionali e centrali, fino al Lazio e all’Abruzzo, mentre è stata di recente introdotta nel meridione and in the islands. The Italic peoples are distinguished from those of Eastern Europe and the North by the fact that the livery is quite different: essentially characterized by the presence of longitudinal bands greenish, more or less thick and continuous, or marmorizzature on a light background, in Italian pike, and pike in Central, East and West Europe are circular or elliptical spots (spot popular livery) yellow or greenish cream background. E 'was also reported the presence of pike with different phenotypes (vertical bars and diagonal) in some ecosystems of central Italy. Now, all this gives rise to much confusion, not only to taxonomic level, but also management, in how often the re-population of this species are made with material imported from Eastern Europe, easier to supply with all the issues that arise at the expense of the original population, including competition and hybridization.
Figure 1: Two examples of the colors of Italian phenotype
Recent
Recent studies have confirmed what some already know: that the Italian populations of Pike, steadily decrease throughout the country because of known problems (habitat alteration reproduction, water pollution, fishing iperprelievo, protective measures random, etc..,), are profoundly different from those across the border, both morphological and genetic, as well as behavioral, to the point to assume a specific differentiation between the Italian pike and the Central and Eastern Europe. In this case, genetics seems to be consistent with the morphological analysis. In detail, recent studies (Conservation genetics of populations of pike in the Veneto Region) by Dr. Livia Lucentini University of Perugia, put up at a Veneto Infoday of Agriculture (Producing and preserving fresh-water fish species), have revealed a substantial correspondence between phenotypes analyzed e genoma corrispondente. In particolare sono state analizzate le livree di poco meno di 1.300 lucci provenienti da differenti siti italiani ed europei, compresi quelli di alcuni allevamenti italiani. Su un campione di 350 esemplari sono quindi state effettuate analisi genetiche, sia mitocondriali che nucleari; queste ultime sono state confrontate con quelle relative a lucci provenienti da un altro continente (Canada). Tra tutti gli esemplari esaminati sono state catalogate 5 livree: a barre diagonali; a barre verticali; a bande longitudinali; livrea marmorizzata; livrea a spot circolari. Dalla comparazione delle sequenze del DNA (mitocondriale e nucleare), si è osservato che i lucci esaminati segregano in due grandi gruppi, diversificati sia geneticamente che a livello di livrea (fenotipo). Nel primo gruppo, compatibile geneticamente con le popolazioni canadesi, segregano tutti i lucci del Nord ed Est Europa ed alcuni italiani (ad esempio quelli del Lago del Corlo, del Lago di Fimon e di alcuni allevamenti). La livrea di riferimento è quella a spot circolari. Nel secondo gruppo segregano tutti i restanti lucci italiani analizzati, compresi quelli di alcune province venete e del Lago Trasimeno. Le livree di riferimento sono le restanti quattro. Questo cosa significa in soldoni? Che le popolazioni attuali, presenti nel territorio italiano, sono ormai costituite per buona parte da lucci alloctoni, caratterizzati da una livrea a spot circolari, mentre le popolazioni native sono in fase di costante decremento. In aggiunta, The discovery in nature of individuals with characteristics intermediate (hybrid) would imply the possibility of genetic introgression between the two lines (or species?) of pike, perhaps only partially limited by reproductive barriers, probably due to different spawning period. However, these, for now, are only hypotheses.
Figure 2: Example of livery of northern pike phenotype of the European Conclusions
In fact is the extreme difficulty in the approach of the Italian populations of esocidi. In fact, the pike, the red list of freshwater fish indigenous in Italy, is considered especially vulnerable. However, the penalty is a question: "What we need to protect or protect pike today?" The answer seems obvious, almost predictable. The species or genetic line is to protect native Italy. So what to do and how to handle pike present in all other inland waters, those characterized by the often cited livery in circular patches or spots, now in the majority? Not to mention the fact that, at managerial level, application practices are thriving as the purchase by public bodies of lots of pike from importers, which, in turn, cross-border purchases. The line to follow, certainly not without problems, it is also still much to investigate in the field of genetics and approaches to people management should, be reliable, based on multidisciplinary analysis: phylogenetic, biological, eco-ethological and genetic. The current line of conservative people of Lucca Italy should therefore follow a few guidelines:
1) Certification and location of the populations in the country;
2) Habitat Protection and recovery, particularly the reproductive;
3) appropriate management measures, both to protect that recovery.
Clearly the primary issue seems to be that of protecting and management of indigenous populations and reproductive habitat, where their presence is established, followed by morphological and genetic selection of breeding stock of pike to be used for artificial reproduction. Less stringent management measures could be taken against people made of non-indigenous people, whose release should be of interest primarily, if not exclusively, private fishing ponds out of touch with public waters. However, there are territorial (in the case of certain waters of Ferrara) in which the pike has been successfully reintroduced (strain Central and Eastern Europe), living in sympatry with a predominantly non-native fish community, exercising his ecological role in a partially degraded environment where the pike "local" would have difficulty surviving.
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