Helminth biocoenosis of Lepus europaeus meridiei (Hilzheimer, 1906) from Pianosa island, Italy

Pianosa is a 10 km(2) Italian island in the Tyrrhenian Sea which is part of the Tuscan Archipelago National Park. In this island lives a brown hare population which, according to the literature, belongs to the ancestral taxon Lepus europaeus meridei that offers a unique opportunity to observe how the parasite biocoenosis shapes in condition of isolation, limited space availability and high population density. The aim of this work is to describe the helminth component community of a non-managed, isolated, and dense hare population, evaluating host-parasite relationship and parasite community structure. All 26 analyzed hares (13 males and 13 females) were in good physical conditions, and all of them harboured exclusively the nematode Protostrongylus oryctolagi only. This is the first report of this lungworm species in Italy. The estimated overall abundance was 48.15 worms per examined hare (range 3-258, median 50) and the parasites were unevenly distributed across host population, with few hosts having most parasites (aggregated or overdispersed distribution). No significant relationship was detected between the number of isolated parasites and hare sex and weigh. The effect of the isolation of Pianosa's hare population seems to have acted reducing parasite richness, while the high host density is probably the cause of the high prevalence and abundance of the single helminth species collected. In conclusion, despite the low impact of parasites confirmed also by the overdispersed parasite distribution, the low diversity of the studied parasite community sounds a warning for the management of the hare population and the whole Pianosa's ecosystem

Quaternary geographical sibling speciation and population structuring in the Eastern Atlantic skates (suborder Rajoidea) Raja clavata and R. straeleni

To access the final version, follow the next link. http://www.springerlink.com/content/t1809472211lk67q/Aim Geographical (allopatric) speciation is a dynamic process whose footprints in the living world are a continuum of stages of increasing divergence. Geographical speciation can also contribute to the evolution of marine taxa. This study looked for two of these evolutionary stages (i.e. structured populations and sibling species) in the diversification patterns of two Atlantic skates (Raja, suborder Rajoidea) which exhibited high morphological and ecological conservativism(undefined

Sexual behaviour and reproductive performance of the endangered European eel Anguilla anguilla (Linnaeus, 1758) based on direct observationsand paternity assignment in semi-natural conditions

European eel Anguilla anguilla is among the highly valued species for aquaculture. Since its peculiar biology, it is not yet possible to complete the whole life cycle in artificial conditions and its supply depends entirely on wild catches. In the last 50 years this species has suffered a population reduction of 99 % mainly due to overfishing. In a conservation perspective, it is of fundamental importance to improve the aquaculture production of European eel, to avoid the extinction of this species and preserve its residual genetic variability, allowing at the same time the fulfilling of costumers request without increasing its harvesting pressure. In this study we aimed to deepen the knowledge about the mechanisms at the basis of reproduction of the European eel in semi-natural conditions, through direct observation of spawning behaviour and through the paternity assignment using microsatellite markers. The systematic and prolonged observation of the reproductive behaviour of European eel and the contextual parentage analyses we carried out for the very first time in this species on 39 adults and 432 F1 randomly collected. We contributed to unravel the sexual behaviour of this species in the most common artificial reproduction conditions (polyandry), and define the precise courtship sequence until the release of gametes, and the male-male hierarchy in courtship. We characterized for the first time three main types of male: dominant (the first who starts the courtship, and the one with the majority of F1 assigned), subordinate (which starts the courtship only in a second time and with a minor percentage of F1 ascribed) and ineffective (which sometime appears totally disinterested to courtship and has few F1 or none). The evidences here produced represent an important attempt for developing good reproduction practices of the critically endangered European eel, providing a good starting point for its future aquaculture production

Evaluating genetic traceability methods for captive bred marine fish and their applications in fisheries management and wildlife forensics

Growing demands for marine fish products is leading to increased pressure on already depleted wild populations and a rise in the aquaculture production. Consequently, more captive bred fish are released into the wild through accidental escape or deliberate restocking, stock enhancement and sea ranching programs. The increased mixing of captive bred fish with wild conspecifics may affect the ecological and/or genetic integrity of wild fish populations. From a fisheries management perspective unambiguous identification tools for captive bred fish will be highly valuable to manage risks. Additionally there is great potential to use these tools in wildlife forensics (i.e. tracing back escapees to their origin and determining mislabelling of seafood products). Using SNP data from captive bred and wild populations of Atlantic cod (Gadus morhua L.) and sole (Solea solea L.), we explored the efficiency of population and parentage assignment techniques for the identification and tracing of captive bred fish. Simulated and empirical data were used to correct for stochastic genetic effects. Overall, parentage assignment performed well when a large effective population size characterizes the broodstock and escapees originate from early generations of captive breeding. Consequently, parentage assignments are particularly useful from a fisheries management perspective to monitor the effects of deliberate releases of captive bred fish on wild populations. Population assignment proved to be more efficient after several generations of captive breeding, which makes it a useful method in forensic applications for well-established aquaculture species. We suggest the implementation of a case by case strategy when choosing the best method

Improving the conservation of Mediterranean Chondrichthyans : the ELASMOMED DNA barcode reference library

Cartilaginous fish are particularly vulnerable to anthropogenic stressors and environmental change because of their K-selected reproductive strategy. Accurate data from scientific surveys and landings are essential to assess conservation status and to develop robust protection and management plans. Currently available data are often incomplete or incorrect as a result of inaccurate species identifications, due to a high level of morphological stasis, especially among closely related taxa. Moreover, several diagnostic characters clearly visible in adult specimens are less evident in juveniles. Here we present results generated by the ELASMOMED Consortium, a regional network aiming to sample and DNA-barcode the Mediterranean Chondrichthyans with the ultimate goal to provide a comprehensive DNA barcode reference library. This library will support and improve the molecular taxonomy of this group and the effectiveness of management and conservation measures. We successfully barcoded 882 individuals belonging to 42 species (17 sharks, 24 batoids and one chimaera), including four endemic and several threatened ones. Morphological misidentifications were found across most orders, further confirming the need for a comprehensive DNA barcoding library as a valuable tool for the reliable identification of specimens in support of taxonomist who are reviewing current identification keys. Despite low intraspecific variation among their barcode sequences and reduced samples size, five species showed preliminary evidence of phylogeographic structure. Overall, the ELASMOMED initiative further emphasizes the key role accurate DNA barcoding libraries play in establishing reliable diagnostic species specific features in otherwise taxonomically problematic groups for biodiversity management and conservation actions.peer-reviewe