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Il presente studio si propone di approfondire la biologia ed il ciclo riproduttivo del gobione italiano (Gobio benacensis), specie endemica a corologia cisalpina inclusa nella categoria “Endangered” (EN) della lista rossa IUCN, con l’intento di fornire informazioni utili a redigere corretti piani gestionali volti alla conservazione della specie. Le indagini sono state condotte in un corso d’acqua del Bacino del Fiume Isonzo (Torrente Reca, Nordest Italia) ed hanno riguardato 86 esemplari catturati nell’aprile 2016 al fine di definirne la consistenza e la struttura della popolazione e 77 esemplari, catturati mensilmente e bimestralmente tra aprile 2016 e febbraio 2017, per la definizione del ciclo riproduttivo. Le curve di regressione del peso sulla lunghezza totale per i maschi (W=0,1253TL2,8770) e per le femmine (W=0,1555TL2,7554), confrontate mediante ANCOVA, non hanno denunciato differenze significative. I valori medi ± deviazione standard dell’indice gonadosomatico GSI per i maschi sono compresi tra 0,61±0,49 e 1,75±0,58, mentre per le femmine tra 1,02±0,88 e 14,15±2,80. L’indice epatosomatico HSI ha denunciato range compresi tra 0,05±0,02 e 2,68±1,26 e tra 0,25±0,19 e 1,75±0,58 rispettivamente per i maschi e per le femmine. Le analisi istologiche di ovari e testicoli, analizzati per la prima volta nella specie, hanno permesso di identificare gli stadi di maturazione, che unitamente all’analisi del GSI indicano che la specie depone le uova a più riprese durante il periodo riproduttivo compreso tra aprile e giugno. Nei maschi è stata, tuttavia, evidenziata una prolungata attività riproduttiva che si protrae fino al mese di agosto.

Il presente lavoro ha avuto come obiettivo l’analisi della trota marmorata Salmo marmoratus in un tratto del Fiume Brenta in cui, nonostante le ripetute operazioni di ripopolamento, le popolazioni sono in costante contrazione. Le analisi, condotte tra ottobre 2016 e dicembre 2017 in tre sottotratti fluviali situati tra il confine tra la Regione Veneto e il Trentino Alto Adige e l’abitato di Cismon del Grappa, hanno riguardato lo le comunità ittiche, gli habitat disponibili per la trota marmorata, lo stato ecologico, la funzionalità fluviale e il comparto chimico-fisico delle acque e dei sedimenti. I risultati hanno evidenziato diverse criticità che compromettono la presenza di popolazioni ben strutturate di Salmo marmoratus nell’area. Tali criticità sono legate a fenomeni di inquinamento genetico, alterazione dell’habitat ed inquinamento delle acque. Sono stati osservati esemplari fenotipicamente puri di Salmo marmoratus (frequenze percentuali 4-25%) e ibridi di trota marmorata e trota fario Salmo trutta. Quest’ultima risulta diffusamente presente nei siti indagati. In rapporto alla superficie dell’alveo bagnato è stata osservata una bassa percentuale di habitat disponibili per la trota marmorata (0-21%), la quale compete per spazi e risorse con la trota fario. L’analisi dello stato ecologico ha denunciato un giudizio sufficiente per tutti i tratti indagati e la presenza di un’alterazione verosimilmente legata a squilibri di tipo trofico evidenziati dai risultati dell’applicazione dell’indice macrofitico RQE_IBMR e dall’analisi delle concentrazioni dei nutrienti in acqua. Ciò è correlabile ad una ridotta capacità autodepurativa del tratto indagato, emersa dall’applicazione dell’Indice di Funzionalità Fluviale e legata agli impatti antropici presenti.

Adriatic sturgeon (Acipenser naccarii) is an endemic species of the Adriatic basin, evaluated as Critically Endangered (CR) by IUCN and therefore near to extinction. This species has a commercial interest and is threaten by overfishing and habitat destruction. These issues caused a dramatic decline of populations that depend on artificial spawning in farms and fish stocking performed by public administrations. The presence of an intensive breeding for conservation purpose have led to the onset of diseases. Among these, viral diseases represent the major issue. In this respect, from 2016 first and foremost in Europe, and then in Italy has been reported the presence of a new Iridovirus (Acipenser Iridovisrus-European) in different sturgeon’s species. Fish Disease laboratory (IZS PLV) received two plots of five individuals belonged to A. naccarii from sturgeon farm located in North Italy. Clinical signs could be attributed to Iridovirus. Subjects have been tested using molecular protocol proposed by Bigarrè et al., (2016). All samples were positive for Iridovirus. This case is the first record of Iridovirus in Adriatic sturgeon in Italy. Unfortunately, the lack of epidemiological data requires a health monitoring to implement prevention measures. Particularly, all sturgeons intended for stoking purpose should be tested to avoid the transmission of disease in wild populations.

The marble trout Salmo marmoratus has been analyzed in a section of the Brenta River, where its populations show constant decrease despite many restocking operations carried out in the area. The study was carried out from October 2016 to December 2017 within three stream stretches placed from the border between Veneto and Trentino Alto Adige regions to the area near the Cismon del Grappa town. Analyses regarded fish communities, habitat availability for Salmo marmoratus, ecological status, fluvial functionality and chemical-physical features. Results highlighted several critical issues for the presence of well-structured marble trout populations, such as hybridization with brown trout Salmo trutta, habitat alteration and water pollution. Within the investigated area, pure Salmo marmoratus specimens (frequencies equal to 4-25%) and hybrids with Salmo trutta (5-27%) were observed. Brown trout was largely present in the area (8-60%). Available habitat ranged from 0 to 21% of the river bed for marble trout, which competes with brown trout for spaces and trophic 37 resources. Ecological state analyses lead to a judgement equal to sufficient for all the stretches due to alteration of the trophic condition, which as highlighted by the macrophytic index RQE_IBMR and by the nutrient concentrations. This is probably related to a reduction of the river functionality, due to the anthropogenic impacts which were detected in the area.

It is well established that fish are directly or indirectly affected by compounds that are toxic or lethal in certain concentrations. Recently the enhancement of the legislative decree n. 172/2015 “Attuazione della direttiva 2013/39/UE, che modifica le direttive 2000/60/CE per quanto riguarda le sostanze prioritarie nel settore della politica delle acque” require the analysis of chemicals compound in biota, particularly in fish and in mollusks/shellfish. The European catfish (Silurus glanis) even thought is an alien species in Italian freshwater, it can be considered a valid bioindicators since it is at the top of food chain, and then can well reflect the contamination of freshwater. In Italy, this species has received an increasing interest in recreational fishing and also for human consumption, with possible risks linked to food safety. Factors as age, sex, size, sexual maturity and breeding season may influence the concentration of contaminants. During the presentation will be set out the results of the research conducted by IZS PLV about this 27 topic, providing ideas and suggestions taking into account the guidelines issued by ISPRA regarding the analysis of the priority substances on biota.

The European eel (Anguilla anguilla) is a catadromous species evaluated as Critically Endangered (CR) by IUCN based on the significant population decline occurred in the last 30 years. The threats on this species are numerous, among these, the presence of the nematode Anguillicoloides crassus and the infection caused by rhabdovirus EVEX (Eel virus European X) represent the major causes of reduction efficiency in eel’s swimming performances, compromising the migration capacity of the species. For the purpose to carry out an experimental test regarding the artificial spawning of 56 this species, some specimens of A. anguilla were captured from some watercourses in Sardegna Region. A few days later, some morbidity event occurred with the appearance of clinical signs as lethargy and hemorrhagic skin lesions of lateral line, fins and head. For this reason, between 2016 and 2017, 53 individuals of A. anguilla were sampled from different watercourses of Sardegna Region. In particular, 20 from Rio Pramaera (Municipality of Lotzorai, OG), 13 from Rio Barca (Municipality of Alghero, SS) and 20 from Flumedosa River (Municipality of Villaputzu, CA) in order to verify the possible presence of the virus in wild populations. The virological analysis (cell lines and PCR end point) were negative for all samples. Nevertheless, it is important to carried out a health monitoring on wild population to investigate the etiological role and the distribution of the virus in wild population of eels.

The aim of the present work is to study the biology and the reproductive cycle of the Italian gudgeon Gobio benacensis, which is included as “endangered” (EN) in the IUCN Redlist, due to the endangered status, information could be useful for the correct management of the species and for the scheduling of focused conservation plans. Analyses were carried out within a watercourse included in the Isonzo River Basin (Reca Stream, Northeast Italy) and regarded 86 specimen collected during April 2016 in order to assess population consistence and structure, and 77 specimens collected monthly and bimonthly between April 2016 and February 2017 to investigate the reproductive cycle. Regression between total length (TL) and body weight (W) obtained for males (W=0,1253TL2,8770) 54 2 and females (W=0,1555TL2,7554) were analyzed using the ANCOVA and did not show significant differences. Mean values of the gonadosomatic index (GSI) ranged from 0,61±0,49 and 1,75±0,58 for males and from 1,02±0,88 and 14,15±2,80 for females. Hepatosomatic index (HIS) showed ranges between 0,05±0,02 and 2,68±1,26 for males and between 0,25±0,19 e 1,75±0,58 for females. Analyses of ovaries and testicles, firstly performed for this species, allowed to identify maturation stages. The results show that G. benacensis females repeatedly spawn during the reproductive period between April and June and that males prolonged reproductive activity until August.

The results of the Working Group on the Systematics and Nomenclature of the italian freshwater fish species established within the AIIAD are showed. The WG, in about four years of activities focused on the current taxonomic situation of Italian fish species (Cyclostomes and Bony Fishes), with special reference to the doubtful cases, in the light of the most recent scientific findings. The considerable amount of literature data collected allowed us to clarify the different points of view expressed by the authors who over time contributed to the deepening of knowledge. The Check-list of the Italian freshwater fish fauna could be a useful tool to reach a shared starting point to fill the existing knowledge gaps. Moreover, this need arises from the awareness that the presence of a univocal scientific nomenclature could play a key role in improving the conservation status of the native fish fauna. Finally, we believe that the scientific debate that will hopefully arise, as well as from the activities within the WG, also from the presentation of the results to the Association, can represent a useful moment of comparison and cultural growth of all members. The checklist with the proposed nomenclature for the Italian freshwater fish fauna, the notes drafted for each of the 5 taxa examined (over 60), the sheets with the minutes of each of the discussion sessions carried out, and the archive including all the literature data collected represent useful tools that, through the website (http://www.aiiad.it), will become a shared heritage of the Association.

Alien species are species introduced by humans (either intentionally or accidentally) outside its natural past or present distribution. Synonyms of “alien” that are widely used are: exotic, allochthonous, introduced, not native species (NNS) or not indigenous. Otherwise, a species occurring in its original area is defined as autochthonous or native or indigenous. In Italy, Zerunian (2004) reports the presence of 48 autochthonous freshwaters species (with 22 endemisms). Nocita and Zerunian (2007) reports 38 allochthonous species, 13 of them are naturalized. The last check list drafted by Italian Association of Freshwaters Ichthyologist (A.I.I.A.D.) in 2016 reported the presence of 72 allochthonous species. The increase is also due to the implementation of new genetics techniques and biogeographic knowledge. The most common negative effects that an alien species may cause are: 1) predation; 2) competition with autochthonous species; 3) changes of the habitat; 4) hybridization with indigenous species; 5) spreading of new pathogenic agents (parasites, bacteria, viruses, fungi) that may be more virulent to new hosts due to the lack of innate immunity in the autochthonous species. In Italy, the introduction of fish fauna from foreign countries, both for restocking or for aquaculture, has been going on for years. Problems related to international trade are not just an Italian issue. In fact, the presence of globalization and the paucity of rules and controls at frontiers has led to the introduction of alien species in the Member States and their spread throughout the territory. A classic example is the Anguillicolosis, a parasitic disease caused by Anguillicoloides crassus (Nematoda), introduced in Europe through the import of Anguilla japonica from Asia. It causes health problems (inflammation of the swim bladder and secondary bacterial infections) in aquaculture facilities and in eel wild populations. In addition, certain pathogens introduced with the import of live fish may potentially be dangerous for humans (zoonotic agents), such as some etheroxenic parasites present in freshwater fish. Health issues are not only related to the introduction of alien species from other countries, but are also extended to the handling of indigenous species from different geographic district within the national territory. Thus, risks from the introduction of alien species are several: while the ecological risks have been repeatedly defined, and reaffirmed at national and international scientific meetings, the health risks are often marginally considered. The aim of this presentation is to contribute to the assessment of alien freshwaters fish introduced in our territory and related health risks.

Con il termine “pesci” indichiamo un gruppo eterogeneo di organismi acquatici muniti di scheletro interno, di pinne e capaci di respirare sott’acqua per mezzo di branchie; comprende specie classificate in tre distinte classi di Vertebrati: i Ciclostomi, animali provi di mascelle appartenenti al gruppo degli Agnati; i Pesci Ossei e i Pesci Cartilaginei, animali provvisti di mascelle appartenenti al gruppo degli Gnatostomi. Nelle acque interne italiane sono presenti solo pesci appartenenti alla classe dei Pesci Ossei e dei Ciclostomi, poiché i Pesci Cartilaginei presenti in tutta Europa vivono esclusivamente in acque marine. Se consideriamo in primo luogo la struttura che sostiene le pinne pari, i Pesci Ossei vengono tradizionalmente suddivisi in 4 sottoclassi: Dipnoi, Crossopterigi, Brachiopterigi e Attinopterigi. Quest’ultima sottoclasse viene ulteriormente suddivisa in tre gruppi (Condrostei, Olostei e Teleostei), anche se la nostra ittiofauna annovera solo rappresentati dei Condrostei e dei Teleostei (Zerunian, 2002). In seguito alle nuove conoscenze derivanti dall’applicazione della genetica molecolare e, sulla base delle nuove conoscenze sulla biologia dell’ittiofauna, la posizione sistematica delle specie ittiche dulciacquicole italiane è stata ed è attualmente sottoposta ad una revisione sistematica che ha portato gli autori di pubblicazioni e di testi in ittiologia ad assumere diversi orientamenti, senza un’uniformità di impostazione, determinando molti dubbi sulla corretta nomenclatura da adottare. Tralasciando il discorso legato alla nomenclatura, il riconoscimento morfologico delle specie ittiche è fondamentale sia per un discorso di tipo economico-commerciale, sia per identificare gli esemplari in casi di mortalità anomale nelle acque libere, eventi sempre più frequenti nel territorio di competenza dell’Istituto Zooprofilattico Sperimentale del Piemonte, Liguria e Valle d’Aosta. Un corretto riconoscimento e una segnalazione tempestiva permetterebbe inoltre di contrastare la diffusione di specie non appartenenti all’ittiofauna nativa, che stanno sempre più minacciando la biodiversità degli ecosistemi acquatici. Nel corso della presentazione, verranno utilizzate chiavi di identificazione e schede descrittive delle principali specie ittiche dulciacquicole presenti nelle acque dolci del Piemonte, Liguria e Valle d’Aosta nonché di quelle introdotte nel corso degli anni. Le chiavi permetteranno l’individuazione della famiglia ad un primo livello e, successivamente ad un secondo, attraverso ulteriori caratteri distintivi esterni per poter pervenire all’identificazione di specie. Le specie ittiche di maggior interesse commerciale, alieutico e conservazionistico all’interno delle tre regioni di competenza possono essere raggruppate in 12 famiglie di cui si presenta una breve rassegna con le principali caratteristiche descrittive (Forneris et al., 1990; Grimaldi & Manzoni,1990; Gandolfi et al., 1991; Kottelat & Freyhof, 2007). Inoltre, vengono indicate le principali specie autoctone del territorio piemontese nelle rispettive famiglie di appartenenza (nomenclatura secondo A.I.I.A.D. versione 1.1., 2016).

Recent studies have addressed to the taxonomical characterization of Italian pike as a new species named Esox cisalpinus, which differs from the European Esox lucius. A taxonomical study of the pike features in the Friuli Venezia Giulia region (Northeast Italy) is here presented, since previous studies did not consider this area which could represent an overlapping zone for the two species. Main meristic characters were investigated, and genetic analyses were carried out using molecular marjers. Our results conform the genetic separation from the E. lucius, while among meristic characters only the number of lateral-line scales differs between the species. E. cisalpinus was observed in most of the investigated sites, except for an isolated lentic habitat where E. lucius was found. As E. cisalpinus is likely autochthonous in friuli venezia Giulia as in other Italian regions, we highlight the requirement of furtheranalyses in order to clarify if hybridization can occur and to plan appropriate management safeguards for native populations.

Il fitoplancton è costituito da organismi vegetali microscopici con scarsa capacità di movimento che vivono in sospensione nelle acque. Questi organismi svolgono negli ecosistemi acquatici il ruolo basilare di produttori primari, per questo motivo, il fitoplancton rappresenta il primo anello della catena alimentare acquatica. Tuttavia, un eccessivo suo sviluppo, sensibile all’arricchimento in nutrienti e sostanze organiche, determina uno scadimento della qualità delle acque. La dominanza dei cianobatteri all’interno delle comunità fitoplanctoniche è una caratteristica osservabile in molti ambienti lacustri. In particolari condizioni ambientali, il loro numero può diventare tuttavia eccessivo rispetto alla densità degli altri gruppi algali, dando origine a fenomeni noti con il nome di fioriture algali. La difficoltà di prevedere lo sviluppo di una determinata popolazione algale non è tuttavia ristretta ai soli cianobatteri, ma riguarda pressoché tutti i gruppi algali, dato l’elevato numero dei fattori che controllano la crescita delle alghe in ambiente pelagico e la complessità delle loro interazioni reciproche. Non tutte le specie di cianobatteri sono tossiche per l’uomo e per gli animali; quelle più comunemente associate a tossicità sono Anabaena, Aphanizomenon, Microcystis, Nodularia, Oscillatoria, Planktothrix e Schizothrix. I cianobatteri producono almeno tre classi di tossine che sono state riconosciute nocive per la salute umana: neurotossine, epatotossine ed endotossine. Sebbene le endotossine siano più comunemente associate a tossicità nell’uomo, l’attenzione dei ricercatori si è da tempo focalizzata sugli effetti, potenzialmente letali, delle neuro ed epatotossine di cui i caratteristici meccanismi d’azione sono stati ben descritti in diversi studi. La presenza di cianobatteri nelle acque interne utilizzate per la pesca, per le attività di acquacoltura e per l’abbeveraggio degli animali rappresentano un problema sanitario emergente in tutto il mondo. La disponibilità di metodi di prova rapidi e accurati, nonché di strategie analitiche efficaci per caratterizzare la presenza di queste biotossine, rappresentano uno strumento essenziale per valutare la loro presenza negli ecosistemi acquatici. Per questo motivo, diversi kit immunoenzimatici ELISA sono stati sviluppati per l’analisi di matrici ambientali ed eventualmente di tessuti animali per la ricerca di microcistine, nodularine, cilindrospermopsine, anatossine e β-N-metilammino-L-alanina. La necessità di riscontrare in maniera tempestiva le cianotissine richiede la messa in pratica di un monitoraggio continuo negli ecosistemi lacustri per permettere l'adozione di misure di prevenzione necessarie a ridurre i rischi di morie di fauna selvatica ed i rischi tossicologici derivanti dal consumo di acqua e prodotti ittici contaminati: si descrivono alcuni esempi di monitoraggio effettuati nel corso del 2016 su ambienti lacustri piemontesi.

This study was seasonally performed over a three year period in a large freshwater temporary pond to investigate (a) seasonal trends of the main abiotic factors, (b) the most important abiotic drivers in shaping macrobenthic invertebrate communities and (c) the structures of these communities among different years. As the study area was placed within a Natural Reserve, the leaf bag technique was used as non invasive sampling method in order to reduce disturbance. The results of chemical and physical investigations point out a clear seasonal trend, while macrobenthic communities differ signifi cantly from year to year, and their main shape drivers were identifi ed to be conductivity, temperature and dissolved oxygen.

In questo studio sono riportati i risultati dell’analisi di flora e vegetazione acquatica in 15 stazioni poste nelle risorgive del Basso Isontino (Comuni di Monfalcone, San Canzian d’Isonzo e Staranzano), area caratterizzata dalla coesistenza di ambienti di elevato valore naturalistico con siti fortemente antropizzati. I dati ottenuti hanno permesso di confermare ed incrementare la conoscenza relativa alla distribuzione di alcune comunità vegetali acquatiche nel Friuli Venezia Giulia. Rispetto, infatti, a studi precedentemente condotti nell’area in esame, sono state rilevate 12 nuove specie e 5 specie segnalate solo storicamente, di cui 2 prima del 1960 e 3 prima del 1920. È stata quindi condotta una correlazione tra parametri biotici e abiotici in ciascuna stazione al fine di verificarne la coerenza con la valutazione dello stato ecologico dei corsi d’acqua ottenuta dal calcolo del Rapporto della Qualità Ecologica relativamente all’indice biotico macrofitico “Biologique Macrophytique en Rivière” (RQE_IBMR) e dall’indice del Livello di Inquinamento dai Macrodescrittori per lo stato ecologico (LIMeco), entrambi previsti dal D.M. 260/2010.

The Orvenco Creek is included in the Basin of Ledra River, that origins partially from an alluvial spring area, placed more northly of the alluvial spring line separating the High plain from the Low Plain of Friuli Venezia Giulia. Fish communities, macrobenthic invertebrates and freshwater macrophytes were investigated to assess the creek ecological status using indices in respect of the D.M. 260/2010 in five samplingstations. Main chemical-physical parameters of water and concentration of main nutrients were monthly measured too. The results showed positive judgements in most cases, especially for LIMeco (high), STAR_ICMi (high) and RQE_IBMR, that showed judgements from good to high and only one case sufficient. The ISECI showed more critical and severe judgements (baed in three stations), due to past and present allochtonous fish species introductions for fisheries. The IFF index was also used, despite not included in the D.M. 260/2010, because it gives valid informationabout the status of frwhwater ecosystems. The IFF index revealed some critical situations not showed by other indices, specially STAR_ICMi and ISECI.

According to the Framework Water Directive, 2000/60/EC, macrobenthic invertebrates are very important as bioindicators for the definition of the ecological Status of lotic systems. I Italy, different collection methods are requested for the application of biotic indices in wadeable and non-wadeable rivers: a proportionally distributed multihabitat sampling (MH) and the use of artificial substrates (AS), respectively. This work was performed to compare the results obtained with both methods in three different lotic environments: an alpine stream, a high plain river and a spring fed channel. Data obtained from the application of the two different techniques have led to a good overlapping of results for all analysed watercourses, even though some macrobenthic invertebrate taxa showed selectivity in the artificial substrate colonization. No significant differences were found even among the metrics of the STAR_ICMi index, provided by the D.M. 260/2010 for the assessment of the watercourses ecological status in Italy.

The Authority of Friuli Venezia Giulia has planned the Regional Water Protection Plan (PRTA), in respect of the Water Framework Directive 2000/60/CE, received in Italy by the D.L. 152/2006. After the identification of 564 water bodies, which are included in four hydroecoregions, has being planned a monitoring program using some bioindicators and supported by chemical and physical analysis. In this study, results of monitoring the fish communities and of the application of the Ecological State of the Fish Communities index (ISECI) for the 29 regional streams of Friuli Venezia Giulia are reported. In addition, the comparisons between results of the ISECI and other indices, which are included in the D.M. 260/2010, are discussed. Finally is discussed a comparison with results of the Ecological State of Macrodescriptor pollution (LIMeco) for chemical-physical analysis.

The Regional Natural Reserve of the Isonzo River Mouth is an Italian coastal area, where biodiversity reaches high levels. Four sampling sites were chosen and seasonal samplings were conducted (autumn 2009 and spring 2010) using a non invasive sampling strategy (leaf bag technique) for studying both detritus processing and colonization by macrobenthic invertebrates. The main chemical and physical water parameters were monitored in water column. Intra - and inter - seasonal differences of the total number, taxa composition, and the vegetable organic matter decomposition rates were investigated. Diptera Chironomidae was the dominant taxon in both seasons, followed by Crustacea. Significant differences were foundfor used community descriptors (total number, number of taxa). Decomposition rates showed dignificant seasonal differences.