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The Red-legged partridge (Alectoris rufa) is a Mediterranean Galliformes, recently classified as Near Threatened by the International Union for the Conservation of Nature, due to the constant and significant decline of its global population. While the gastrointestinal parasites of the species are well studied in some part of its range (Iberian peninsula), limited information is available for the Italian populations, that represent the eastern limit of the species range. This study was conducted to fill this gap of knowledge, determining the composition, richness, prevalence, intensity and abundance of A. rufa gastrointestinal parasite community in two populations in Italy. During the autumn seasons 2008–2009 and 2009–2010, necropsies were conducted on 18 Red-legged partridge from the southern part of Alessandria province (Piedmont, northwestern Italy) and 34 from the Parma province (Emilia Romagna, northern Italy). All the animals were examined for the presence of gastrointestinal parasites. Additionally, 229 fecal samples were collected from live animals in Alessandria province. Prevalence, abundance and intensity of infection were calculated for each parasite species, except for coccidia for which only the prevalence was determined. The following parasites were observed: Heterakis gallinarum, Ascaridia spp., Ascaridia columbae, Raillietina spp., Eimeria spp. The highest parasite prevalence was found in Alessandria province for Eimeria sp., infecting almost half of the sampled animals (P: 45%, CI95%: 39–51). Eimeria sp. was also the most prevalent parasite in Parma province but with much lower prevalence (P: 19%, CI95%: 5–32). Intestinal helminths prevalence ranged from 3% (CI95%: 0–9) for A. columbae and Raillietina spp. (Parma Province) to 9% for H. gallinarum in both Parma (CI95%: 0–19), and Alessandria province (CI95%: 0–22). To our knowledge, this is the first study providing information on the gastrointestinal parasites of the Red-legged partridge in Italy. Ascaridia columbae, a parasite typical of the domestic pigeon, was reported for the first time in A. rufa. The epidemiological descriptors reported herein could serve as a basis for future studies, allowing for epidemiological comparison across countries, locations, and time periods.

The systematic status of the Italian trout in the Salmo trutta L., 1758 complex (including marble, Mediterranean and lacustrine trout), has long been - and is still today – subject of controversies among ichthyologists. The specific name and the taxonomic rank changed several times in the last years, and the natural occurrence of this salmonid fish in some Italian areas was debated due to spread of alien strains. The main difficulty with the taxonomy of the Italian trout stems from the impossibility of disentangling it “on paper” or, even worse, trying to face this systematic issue considering only a very limited (local/national scale) part of the brown trout range. The taxonomy of the Italian trout population is inextricably linked to the necessity of clarifying first phylogeny and phylogeography in an overall Mediterranean context. The opportunity of a non “self-referential” taxonomy is even more fundamental for a vulnerable salmonid like the Italian brown trout, for which there is a very conflicting management problem related to sport fishing and, at the same time, the urgent need for effective conservation measures. It is however necessary to emphasize that conservation is independent from taxonomy but must start from the level of the local population. In fact, management units need stability and they cannot, therefore, coincide with entities – the Linnean species – requiring continuous taxonomic revisions. Modern molecular methods are the best tools for defining these units of management and conservation in an evolutionary perspective.

Freshwater ecosystem functioning is often thought to be dominated by fish, determining the community structure via top-down control and ecosystem engineering. However, freshwater crayfish can have an even stronger effect on food web and ecosystem functioning, operating as keystone species in a water body (Longshaw and Stebbing, 2016). As environmental engineers, crayfish have a significant impact on the biodiversity within their habitat (Souty-Grosset et al., 2006). Yet over the past 150 years freshwater crayfish in Europe have faced a novel challenge in the form of a lethal disease caused by the oomycete Aphanomyces astaci Schikora 1906, introduced by alien crayfish species of North American origin. Today, the European native crayfish population trends are in decline nearing extinction in several cases (Souty-Grosset et al., 2006; Jussila et al., 2014). The introduction of different A. astaci strains in Europe and the repeated introductions of their North American host species are a classic example of a man-made ecological disaster (Jussila et al.), stemming from the naive belief that the manipulation of an ecosystem would be straightforward. The alien crayfish species, which were supposed to replace the eradicated native stocks, not only transfer the deadly disease but in many parts of Europe also outcompete their native crayfish counterparts, because they are more aggressive giving them additional advantage regarding habitat competition in addition to higher fecundity (Alonso and Martínez, 2006). Introductions of new alien crayfish stocks and thus new A. astaci strains will inevitably lead to the total eradication of the remaining native European crayfish stocks. In this Research Topic we collected scientific work on crayfish conservation from multiple scales, ranging from molecular to species and ecosystem levels, to address the consequences of invasive crayfish and host-parasite interactions on European freshwater biodiversity and ecosystem functioning, aiding conservation and management of European freshwater crayfish to prevent them from extinction.

More than three million farmed mallards are released annually for hunting purposes in Europe. The ecological impact of these releases depends on how many birds survive to join the wild breeding population. We estimated annual survival in farmed-released and wild-caught Swedish mallards, using mark-recapture data. In 2011–2018, we ringed 13,533 farmed ducklings before release (26.5% recovered). Most recoveries were birds shot at the release site, while only about 4% were found >3 km away. In 2002–2018, 19,820 wild mallards were ringed in Sweden, yielding 1369 (6.9%) recoveries. Like in farmed-released birds, most recoveries were by hunting, but 91.1% of recovered wild mallards were >3 km away from the ringing site. Annual survival rate in farmed-released mallards (ringed as pulli) was 0.02. In wild mallards (ringed as fledged or fully grown), annual survival was lower in females (0.64) than in males (0.71). At two sites in 2018, farmed ducklings were released in two batches 3 weeks apart to study the effect of early versus late release date, while controlling for body condition (BCI). Ducklings released early had a higher BCI and were recovered earlier (lower longevity) than those released late. Individual BCI and longevity were not correlated in recovered ducklings. Based on our estimate of annual survival in farmed-released mallards, a substantial number, i.e., 5000 (95% CI, 3040–6960), join the wild population annually. Despite being fed, a large proportion of released ducklings does not survive until the hunting season. Early releases may maximize pre-hunting survival. Repeated releases may prolong hunting opportunities and increase hunting bags.

Common practices in current game management are wetland restoration and creation, as well as releases of quarry species. We studied the impact of releases of mallard ducklings on species richness of wild waterbirds and amphibians on three types of wetlands: natural, constructed and restored. Data on species richness, macrophyte cover and water characteristics (total phosphorous and pH) were collected at 32 sites in an agricultural landscape in southern Sweden. In total, 14 species of waterbirds were recorded, ranging from zero to seven per wetland and survey. Amphibians were present in 24 of the 32 wetlands; in total five species were found, ranging from zero to three per wetland. By using generalized linear modelling we found that wetland type best predicted waterbird species richness. Constructed wetlands had significantly more waterbird species, regardless of whether they were used for mallard releases or not. There were breeding amphibians in 62% of natural, 100% of restored and 77% of constructed wetlands. Breeding amphibians were present in 84% of wetlands without, and in 62% of wetlands with releases. However, included variables did not explain amphibian species richness in the wetlands. Releasing large numbers of mallards on a wetland and providing food ad libitum is likely to affect water quality, nutrient availability and predation pressure. Indeed, phosphorous levels were significantly higher in release wetlands, but no differences were found between wetland types.This means that mallard releases may increase nutrient loads in environments that are already eutrophied. However, in our study system releases did not influence species richness of waterbirds and amphibians locally. Constructing wetlands for mallard releases can thus have positive local effects on species richness.

International audience; Parentage assignment with genomic markers provides an opportunity to monitor salmon restocking programs. Most of the time, it is used to study the fate of hatchery-born fish in those programs, as well as the genetic impacts of restocking. In such analyses, only fish that are assigned to their parents are considered. In the Garonne-Dordogne river basin in France, native salmon have disappeared, and supportive breeding is being used to try to reinstate a self-sustained population. It is therefore of primary importance to assess the numbers of wild-born returning salmon, which could appear as wrongly assigned or not assigned, depending on the power of the marker set and on the size of the mating plan. We used the genotypes at nine microsatellites of the 5800 hatchery broodstock which were used from 2008 to 2014, and of 884 upstream migrating fish collected from 2008 to 2016, to assess our ability to identify wild-born salmon. We simulated genotypes of hatchery fish and wild-born fish and assessed how they were identified by the parentage assignment software Accurassign. We showed that 98.7% of the fish assigned within the recorded mating plan could be considered hatchery fish, while 93.3% of the fish in other assignment categories (assigned out of the mating plan, assigned to several parent pairs, not assigned) could be considered wild-born. Using a Bayesian approach, we showed that 31.3% of the 457 upstream migrating fish sampled from 2014 to 2016 were wild-born. This approach is thus efficient to identify wild-born fish in a restoration program. It remains dependent on the quality of the recording of the mating plan, which we showed was rather good (

Due to the ecological importance of Lophiosilurus alexandri, the present work evaluated its genetic representativeness by comparing wild stocks to broodstocks that were kept at three restocking hatcheries along the São Francisco River. A total of 97 samples were genotyped for newly developed microsatellite markers. Low levels of genetic diversity (average alleles number of 4.2 alleles) were detected in all cases, being more severe in captive groups. Significant pairwise FST and DEST values, Structure, and DAPC analyses showed that wild animals were structured in two groups, and a third group was formed by captive animals, evidencing the need to adopt genetic criteria to retain genetic diversity in the hatcheries. For this reason, three full-sib families were constructed to select the best relatedness estimator for L. alexandri and establish a cut-off value aimed to avoid full-sibling matings in the hatcheries. Two estimators, Wang (RW) and Lynch & Li (RLL), were accurate in reflecting the relatedness level for full-sibs in this species. According to them, less than 50% of the potential breeding matings in the three hatcheries are advisable. The innate low diversity of L. alexandri highlights the importance of minimizing inbreeding and retaining genetic diversity towards the species recovery. Resumo Devido à importância ecológica de Lophiosilurus alexandri, o presente trabalho avaliou sua representatividade genética, comparando estoques selvagens com plantéis de reprodutores de três larviculturas ao longo do Rio São Francisco. Noventa e sete amostras foram genotipadas com marcadores microssatélites recém-desenvolvidos. Baixos níveis de diversidade genética (número médio de alelos de 4,2) foram detectados em todos os casos, sendo mais severo no cativeiro. Os valores de FST e DEST par a par, as análises do Structure e DAPC mostraram a estruturação dos animais selvagens em dois grupos, e um terceiro formado pelas larviculturas, evidenciando a necessidade de adoção de critérios genéticos para retenção da diversidade genética no cativeiro. Por essa razão, três famílias de irmãos completos foram construídas para selecionar o melhor estimador de parentesco para a espécie e estabelecer os valores mínimos de corte para evitar cruzamentos indesejados. Dois estimadores, Wang (RW) e Lynch & Li (RLL), foram eficientes em refletir as relações de parentesco para irmãos completos nessa espécie. Segundo eles, menos de 50% dos potenciais cruzamentos são recomendáveis nas três larviculturas. A baixa diversidade genética inerente ao L. alexandri destaca a importância de minimizar a consanguinidade e evitar perda de diversidade genética, visando a recuperação da espécie.

The present study aimed to investigate and compare fitness-related traits and ploidy levels of purebreds and hybrids produced from sturgeon broodstock with both normal and abnormal ploidy levels. We used diploid Acipenser ruthenus and tetraploid A. baerii males and females to produce purebreds and reciprocal hybrids of normal ploidy levels. Likewise, we used diploid A. ruthenus and tetraploid A. baerii females mated to pentaploid and hexaploid A. baerii males to produce hybrids of abnormal ploidy levels. Fertilization of ova of A. ruthenus and A. baerii of normal ploidy with the sperm of pentaploid and hexaploid A. baerii produced fully viable progeny with ploidy levels that were intermediate between those of the parents as was also found in crosses of purebreds and reciprocal hybrids of normal ploidy levels. The A. ruthenus &times, pentaploid A. baerii and A. ruthenus &times, hexaploid A. baerii hybrids did not survive after 22 days post-hatch (dph). Mean body weight and cumulative survival were periodically checked at seven-time intervals. The recorded values of mean body weight were significantly higher in A. baerii &times, pentaploid A. baerii hybrids than other groups at three sampling points (160, 252 and 330 dph). In contrast, the highest cumulative survival was observed in A. baerii &times, A. ruthenus hybrids at all sampling points (14.47 &plusmn, 5.70 at 497 dph). Overall, most of the studied sturgeon hybrids displayed higher mean BW and cumulative survival compared to the purebreds. The utilization of sturgeon hybrids should be restricted to aquaculture purposes because they can pose a significant genetic threat to native populations through ecological interactions.

Hatchery-reared sterlet originating from the Danube and Volga river basins that showed population-discriminatory alleles on at least one microsatellite locus were used to produce purebred (within-population) and hybrid crosses to evaluate intraspecific hybridization with respect to the genetic polymorphism and physiological fitness of fish for commercial aquaculture and, conservation programs. Reciprocal crossing assessed the effect of parent position. The fish were reared in indoor and outdoor tanks and monitored over 504 days for growth traits. The highest final mean body weight (144.9 &plusmn, 59.5 g) was recorded in the Danube (♀) &times, Volga (♂) hybrid and the highest survival in the Volga (♀) &times, Danube (♂) hybrid. The Volga purebred exhibited the lowest mean body weight (124.8 &plusmn, 57.6 g). A set of six microsatellites was used to evaluate the heterozygosity. The mean number of alleles was highest in the Danube (♀) &times, Volga (♂) hybrid and lowest in the Volga purebred, suggesting an influence of the parent position in the hybridization matrix. The higher level of genetic polymorphism, as in the Danube (♀) &times, Volga (♂) hybrid, may confer greater fitness in a novel environment. Our analysis revealed that the intraspecific hybrids performed better than the purebred fish in the controlled and suboptimal rearing conditions.

espanolAntecedentes: Mantener la diversidad genetica de los peces salvajes es una consideracion importante para los programas de repoblacion, ya que la endogamia puede comprometer la supervivencia de la progenie y afectar la supervivencia de las poblaciones naturales. Objetivo: Evaluar la influencia del metodo de desove (seminatural - SN o en franjas - ST) y el numero de reproductores (1♀:3♂ y 2♀:6♂) sobre la eficiencia reproductiva y la diversidad genetica de progenies de B. orbignyanusdestinados a la restauracion de poblaciones silvestres. Metodos: Se monitorearon las tasas de fertilizacion, eclosion y mortalidad de reproductores. Para las evaluaciones geneticas (frecuencias alelicas, heterocigosidad observada y esperada, indice de Shannon, coeficiente de endogamia, analisis de varianza molecular y diferenciacion genetica) los reproductores (n=24) y su progenie (90 larvas/tratamiento) se muestrearon y analizaron utilizando ocho marcadores microsatelites. Resultados: La interaccion entre el metodo de desove y el numero de reproductores no fue significativa (p>0,05). Se obtuvieron mejores tasas de fecundacion y eclosion (p0,05). Los loci de microsatelites amplificados produjeron un total de 30 alelos con tamanos entre 80 y 225 pb, y sus frecuencias indicaron un aumento (p0,05). Conclusion: Los metodos de desove y el numero de reproductores evaluados aumentaron de la misma manera la diversidad genetica de las progenies, con baja diferenciacion genetica entre tratamientos. En contraste, las tasas de fecundacion, eclosion y mortalidad de peces reproductores revelaron que el SN tuvo la mejor eficiencia reproductiva, un hecho relacionado con el estres del manejo y las lesiones causadas por el ST. Por lo tanto, el SN demuestra ser el metodo de desove mas adecuado para B. orbignyanus en los programas de repoblacion. EnglishBackground:Preserving the genetic diversity of wild fish is an important consideration for restocking programs, as inbreeding can compromise progeny survival as well as impact the resilience of natural populations. Objective: To evaluate the influence of spawning method: semi-natural (SN) or strip-spawning (ST), and the number of breeders (1♀:3♂ and 2♀:6♂) on the reproductive efficiency and genetic diversity of B. orbignyanus progeny destined for restoration of wild stocks. Methods: Rates of fertilization, hatching and broodfish mortality were recorded. For genetic evaluations (allele frequency, observed and expected heterozygosity, Shannon index, inbreeding coefficient, molecular variance analysis, and genetic differentiation), breeders (n=24), and their progenies (90 larvae/treatment) were sampled and analyzed using eight microsatellite markers. Results: Higher fertilization and hatching rates, and lower broodfish mortality were observed for the SN method (p0.05). Interaction between spawning method and number of breeders was not significant (p>0.05). The amplified microsatellite loci produced a total of 30 alleles, with sizes between 80 and 225 bp and their frequencies indicated an increase (p0.05). Conclusion: The spawning methods and number of breeders tested increased equally the genetic diversity of the progeny, with low genetic differentiation between treatments. In contrast, rates of fertilization, hatching and brood fish mortality revealed that the SN method resulted in the best reproductive efficiency due to the handling stress and injuries caused by ST. Thus, SN proves to be the most suitable spawning-method for B. orbignyanus in restocking programs. portuguesAntecedentes: A manutencao da diversidade genetica dos peixes selvagens e uma importante consideracao para programas de repovoamento, ja que a endogamia pode comprometer a sobrevivencia da progenie, alem de impactar na resiliencia das populacoes naturais. Objetivo: Avaliar a influencia do metodo de desova (semi-natural – SN ou por extrusao – ST) e numero de reprodutores (1♀:3♂ e 2♀:6♂) na eficiencia reprodutiva e na diversidade genetica de progenie de B. orbignyanus destinados a recuperacao de estoques selvagens. Metodos: Taxas de fertilizacao, eclosao e mortalidade de reprodutores foram monitorados. Para avaliacoes geneticas (frequencias alelicas, heterozigosidade observada e esperada, indice de Shannon, coeficiente de endogamia, analise de variância molecular e diferenciacao genetica), reprodutores (n=24) e sua progenie (90 larvas/tratamento) foram amostrados e analisados utilizando oito marcadores microssatelites. Resultados: Interacao entre metodo de desova e numero de reprodutores nao foi significante (p>0,05). Melhores taxas de fertilizacao e eclosao (p0,05). Os loci microssatelites amplificados produziram um total de 30 alelos, com tamanhos entre 80 e 225 pb e suas frequencias indicaram aumento (p0,05). Conclusao: Os metodos de desova e numeros de reprodutores avaliados aumentaram igualmente a diversidade genetica das progenies, com baixa diferenciacao genetica entre tratamentos. Em contraste, as taxas de fecundacao, eclosao e mortalidade de reprodutores revelaram que SN obteve a melhor eficiencia reprodutiva, fato relacionado com o estresse de manipulacao e injurias causadas por ST. Por isso, SN se mostrou como o metodo de desova mais adequado para B. orbignyanus em programas de repovoamento.

Italian native populations of Mediterranean brown trout belong to the Salmo trutta complex. This species complex includes many mitochondrial lineages and phenotypes that have caused taxonomic controversies over time. The spatial distribution and the genetic diversity of these fishes are threatened by habitat destruction, global warming and, mainly, by the introduction of domestic trout of Atlantic origin. Indeed allochthonous trouts were massively restocked in Italian rivers for a century and they admixed with native populations. In order to identify residual native populations of Mediterranean brown trout, a genetic analysis of specimens collected within Latium region, on the Tyrrhenian slope of central Italy, was undertaken. To this purpose, 210 trout specimens were collected from six different rivers and analyzed for the identification of their nuclear (LDH-C1* RFLP) and mitochondrial (Control Region sequences) genotypes. Genetic characterization with these molecular markers allowed a quantitative estimate of allochthonous genotypes, which are present in all brown trout populations of the six sites, even if not equally distributed across the sampling area. At least three populations, inhabiting diverse lotic ecosystems (mountain, hilly and coastal streams respectively), are characterized by a high percentage of native nuclear allele *100 at locus LDH-C1* and typical Mediterranean haplotypes (of AD and ME lineages), which can be considered as different management units (MUs). This finding highlighted the aquatic ecosystems of the Latium Region as an important hotspot of salmonid biodiversity within the Italian peninsula, with important implications from a conservation perspective.

The impact of escapees from aquaculture is of general concern for the sustainability of natural resources. Turbot Scophthalmus maximus is a marine flatfish of great commercial value whose land-based aquaculture started approx. 40 yr ago; hence, a low impact of escapees is expected on wild populations. However, enhancement of wild stocks using farmed turbot has been carried out along the Northeast Atlantic coasts in the last decades. Recently, a broad panel of single nucleotide polymorphism (SNP) markers (755 SNPs; 1 SNP Mb−1) has been used to evaluate the genetic structure of turbot throughout its distribution range, constituting the baseline to evaluate the impact of farmed fish in the wild. Two distinct origins were identified for farmed turbot (F_ORI1 and F_ORI2; FST = 0.049), which differentiated from wild populations after 5 generations of selection (average FST = 0.059), and consistent evidence of adaptation to domestication was de - tected. A notable proportion of fish of farmed ancestry was detected in the wild (15.5%), mainly in the North Sea, where restocking activities have taken place, determining genetic introgression in wild populations. Conversely, effects of land-based aquaculture appear negligible. A simulation exercise supported panels of 40 and 80 SNPs to identify fishes of F_ORI1 and F_ORI2 ancestry in the wild, respectively. Application to empirical data showed an assignment success (wild/farmed ancestry) of approx. 95% in comparison with the full SNP dataset. The SNP tools will be useful to monitor turbot of farmed ancestry in the wild, which might represent a risk, considering the lower fitness of farmed individuals The project was funded by the 7th Framework Programme for research (FP7) under ‘Knowledge-Based Bio-Economy — KBBE’, Theme 2: ‘Food, Agriculture and fisheries, and Biotechnologies’ Project identifier: FP7-KBBE-2012-6-singlestage Grant agreement no.: 311920 ‘The development of tools for tracing and evaluating the genetic impact of fish from aquaculture: AquaTrace’ and the Spanish Regional Government Xunta de Galicia GRC2014/010. Ciência sem Fronteiras/CAPES − Brazil supported the fellowship for the stay of F.D.P. at USC SI

Biometric character analyses were conducted on Atlantic sturgeon Acipenser oxyrinchus, a species included in a re-establishment programme in the Baltic Sea basin. The study sought to identify measurable and countable characters most useful for distinguishing A. oxyrinchus from three alien species found in open waters of Poland: Acipenser baerii, Acipenser gueldenstaedtii, and Acipenser stellatus. Measurable characters that contributed most to discrimination included preorbital distance, eye diameter, ventral fin base to anal fin base, and postorbital distance. Among countable characters, the number of lateral scutes made the greatest contribution. The data from the present study may be used to supplement existing systematic keys and lay the foundations for creating a catalogue or atlas of popular species and interspecific hybrids of sturgeon, including their complete systematic determination.

Genetic diversity is crucial for the adaptation of exploited species like the pink abalone (Haliotis corrugata), faced with threats from climate change, overfishing and impacts associated with aquaculture production. While marine reserves are commonly used to mitigate risks to marine populations, the duration, size, location and larval connectivity needed for a reserve to help conserve genetic resources is still poorly understood. Here, we examine the effects of fishing, reserves, and restocking on the genetic diversity of 10 populations from central Baja California, Mexico, and Southern California, USA. We demonstrate that each population shows characteristic genetic signatures according to recent management decisions. We found high allelic diversity, particularly rare alleles, a larger effective population size and a lack of a recent genetic bottleneck in pink abalones within a small (0.8 km2), recently established (5 years) reserve in Baja California, compared to other fished sites after a climatic bottleneck. Higher diversity may result from the presence of older animals in the reserve. Due to its location, the reserve may also act as an important hub connecting distant populations via larval dispersal. In contrast, a population from California showed genetic isolation, loss of allelic diversity and high relatedness, consistent with the collapse of fisheries in the 1990s and their lack of recovery thereafter. In addition, a fished area in Baja California with a history of restocking for over a decade showed an increase in frequency of related individuals and high genetic differentiation from nearby sites that were consistent with the production of larvae from a few adults in the laboratory. A network of strategically placed small marine reserves that considers ocean circulation patterns could help to maintain genetic diversity and connectivity of exploited populations.

Determining the genetic population structure and intraspecific evolution of species is important for efficient management. Here we investigated 394 sequences of the mtDNA cyt b of the critically endangered European eel, Anguilla anguilla . We found 62 different haplotypes, among which 32 novel ones. All those sequences were grouped into 9 haplogroups on the basis of their frequency and links in the haplotype network. Two pairwise comparisons revealed significant genetic differentiation between regions. One comparison indicated small (ΦST = 0.02768; P = 0.0071) genetic differentiation between the Atlantic Ocean and the North Sea. Another comparison indicated small (ΦST = 0.01144; P = 0.0440) genetic differentiation between eel samples caught in the Baltic Sea, the Curonian Lagoon and the Gulf of Riga and those captured in the North Sea. The results of the study are in agreement with the recent findings obtained using the mtDNA D-loop region as a molecular marker, indicating that although A. anguilla is considered a panmictic species the genetic structure of its population indicated by mtDNA markers could be characterized as a genetic mosaic.

Disruption of naturally evolved spatial patterns of genetic variation and local adaptations is a growing concern in wildlife management and conservation. During the last decade, releases of native taxa with potentially non-native genotypes have received increased attention. This has mostly concerned conservation programs, but releases are also widely carried out to boost harvest opportunities. The mallard, Anas platyrhynchos, is one of few terrestrial migratory vertebrates subjected to large-scale releases for hunting purposes. It is the most numerous and widespread duck in the world, yet each year more than three million farmed mallard ducklings are released into the wild in the European Union alone to increase the harvestable population. This study aimed to determine the genetic effects of such large-scale releases of a native species, specifically if wild and released farmed mallards differ genetically among subpopulations in Europe, if there are signs of admixture between the two groups, if the genetic structure of the wild mallard population has changed since large-scale releases began in the 1970s, and if the current data matches global patterns across the Northern hemisphere. We used Bayesian clustering (Structure software) and Discriminant Analysis of Principal Components (DAPC) to analyze the genetic structure of historical and present-day wild (n = 171 and n = 209, respectively) as well as farmed (n = 211) mallards from six European countries as inferred by 360 single-nucleotide polymorphisms (SNPs). Both methods showed a clear genetic differentiation between wild and farmed mallards. Admixed individuals were found in the present-day wild population, implicating introgression of farmed genotypes into wild mallards despite low survival among released farmed mallards. Such cryptic introgression would alter the genetic composition of wild populations and may have unknown long-term consequences for conservation. published

International audience; Salmonid juvenile stocking programs are often poorly monitored due to the lack of identification between stocked and wild fish. In this study, a hierarchical Bayesian model is developed to take advantage of spatiotemporal variations of stocking and wild recruitment for estimating these two components despite the absence of identification data. It is first tested by means of simulated data and then applied to the 37 year abundance data set of the Atlantic salmon (Salmo salar) population of the Allier catchment (France). Despite the absence of identification data, juvenile densities could be estimated and split into wild and stocked components. We found that the stocked juveniles contributed significantly to the total juvenile production, while the wild reproduction continued to provide an important contribution. This approach is encouraging and promising from a management advice perspective. It is flexible enough to accommodate for case study specificities and shows that long-term monitoring abundances can be useful to assess the impact of stocking programs even in the absence of direct means of identifying stocked versus wild fish.

The success of restocking (releasing hatchery-reared juveniles in the wild) depends on the capacity of phenotypes that are already adapted to captivity to readapt to the natural environment. Changes in growth rate after release can be monitored to determine whether released fish are adapting well to the natural environment or failing to adjust to wild conditions. Nevertheless, it is not known whether released individual fish experience a shift in growth rate. Alternatively, the fish showing long-term survival could be those that were already larger before release. This question is relevant for the maximization of stocking success because certain phenotypes (those with a better probability of readapting) could be selected for release. This study compared the somatic growth of released and recaptured meagre, Argyrosomus regius, with control (captive) meagre belonging to the same cohort. Recaptures that had spent less than 3. months at liberty showed the same length-at-age as the control fish, but the length-at-age of many recaptured fish that had spent more than 3. months at liberty was greater than expected. The otolith radius of the growth mark corresponding to the first year of life (i.e., when all fish were still in captivity) was significantly greater for fish that had spent more than 3. months at liberty, indicating that these meagre were larger and had a higher growth rate when they were released. Moreover, the analysis of daily otolith growth before and after release showed that most of the recaptured meagre that had spent less than 3. months at liberty grew an equal or lesser amount in the wild than before release. In contrast, most of the recaptures that had spent more than 3. months at liberty showed a higher growth rate after release. Therefore, results are discussed in light of the combined effect of differential survival and increased growth, although the low sample size requires interpreting the results carefully. © 2014 Elsevier B.V., This work was financially supported by INIA projects RTA-2007 00033-C02-01 and RTA-2011 00056-C02-00

The European rabbit (Oryctolagus cuniculus) is endemic to Mediterranean ecosystems in the Iberian Peninsula, where it is a key species. In recent years its populations have declined due to several factors including habitat transformation and viral diseases. At the same time, corrective measures including population restocking in areas with low population densities using rabbits from other geographical areas have been performed. In this study we evaluate the impact restocking has had on the population dynamics of native rabbits in the Doñana National Park. As part of the natural processes monitoring program carried out in the Doñana Biological Station (ESPN-EBD-CSIC), rabbit censuses were conducted in spring and late summer in 2005–2015 at dusk and at night along six fixed transects in habitats harbouring rabbit populations.In order to take into account restocked rabbit numbers, annual reports from the Doñana Natural Area and data provided by the Lynx team of the LIFE project were incorporated into the study. In all, 52 336 rabbits from different parts of western Andalusia were released in the Doñana Biosphere Reserve in 2005–2015. Yet, rabbit populations underwent significant declines, above all in 2013 and 2015, with decreases in some areas of up to 80%. These results show intensive rabbit restocking did not increase the native rabbit populations numbers. The impact of the release of rabbits on the population dynamics of the species in Doñana is discussed. Keywords: Oryctolagus cuniculus, Restocking, Iberian peninsula, Carnivores, Doñana

Rates of hybridization and introgression are increasing dramatically worldwide because of translocations, restocking of organisms and habitat modifications; thus, determining whether hybridization is occuring after reintroducing extirpated congeneric species is commensurately important for conservation. Restocking programs are sometimes criticized because of the genetic consequences of hatchery-bred fish breeding with wild populations. These concerns are important to conservation restocking programs, including those from the Australian freshwater fish family, Percichthyidae. Two of the better known Australian Percichthyidae are the Murray Cod,Maccullochella peeliiand Trout Cod,Maccullochella macquariensiswhich were formerly widespread over the Murray Darling Basin. In much of the Murrumbidgee River, Trout Cod and Murray Cod were sympatric until the late 1970s when Trout Cod were extirpated. Here we use genetic single nucleotide polymorphism (SNP) data together with mitochondrial sequences to examine hybridization and introgression between Murray Cod and Trout Cod in the upper Murrumbidgee River and consider implications for restocking programs. We have confirmed restocked riverine Trout Cod reproducing, but only as inter-specific matings, in the wild. We detected hybrid Trout Cod–Murray Cod in the Upper Murrumbidgee, recording the first hybrid larvae in the wild. Although hybrid larvae, juveniles and adults have been recorded in hatcheries and impoundments, and hybrid adults have been recorded in rivers previously, this is the first time fertile F1 have been recorded in a wild riverine population. The F1 backcrosses with Murray cod have also been found to be fertile. All backcrosses noted were with pure Murray Cod. Such introgression has not been recorded previously in these two species, and the imbalance in hybridization direction may have important implications for restocking programs.

Introduction of non-indigenous taxa by anthropogenic activities may lead to the generation of hybrid forms and cause genetic pollution of native species. Populations of different Salmo species are threatened in Italy by hybridization and introgression caused by allochthonous lineages introduced since historical times. In particular, Salmo marmoratus is currently sympatric with domestic lineages of Salmo trutta in most of its native geographical range and reproductive interfecundity between the two taxa is seriously threatening the genetic purity of the endemic species. To fulfill conservation purposes and fisheries management, an investigation based on single and multilocus DNA fingerprinting was carried out both to assess marble trout genetic diversity and the method’s amenability to restocking practices. RFLPs (Restriction Fragments Length Polymorphisms) and SNPs (Single Nucleotide Polymorphisms) in mitochondrial 16 S rDNA, D-loop, and nuclear LDH-C1* sequences were genotyped in more than 350 samples collected from different hatcheries in Northern Italy. The combination of the three markers allowed the selection of putative pure individuals of S. marmoratus to be submitted to additional highly polymorphic AFLPs (Amplified Fragment Length Polymorphisms) analyses. Additional benefits of AFLPs over other techniques emerged in connection with their potential power for fish stock identification. In fact, 52% of all analyzed samples were potentially pure marble trout, 4% were pure Atlantic trout and 44% were hybrids showing different combinations of haplotypes/genotypes. The combined approach demonstrated improved resolution to reveal hybridization not detected by classical diagnostic markers, and to select breeders for reintroduction programs.

Captive breeding and reintroduction programs remain a powerful but divisive tool for management of threatened species, with a proven potential to avoid extinction, but low long-term success rates and high resource requirements. Monitoring the results of reintroductions is critical to be able to assess short- and long-term success, adjusting management decisions as new information becomes available. In this study, we assessed the first 15 years of the captive breeding and restocking program for the European pond turtle Emys orbicularis in Liguria, northern Italy. We estimated survival of released turtles by modelling mark-recapture monitoring data. We then used those estimates to update our prior expectations about long-term outcomes, and to adjust management decisions about the age of individuals to release. Modelling results suggest released turtles had sufficiently high survival, matching prior expectations, such that local extinction has been averted in the short-term. Survival was similar among candidate age classes for releases, suggesting the release of younger individuals can provide positive outcomes while reducing management costs. On the other hand, survival varied among sites, indicating the need for ongoing in-situ habitat management to ensure long-term persistence. Moreover, the late onset of sexual maturity in the species means reproduction of released animals cannot yet be determined with certainty. Captive breeding and reintroduction programs normally require long-term efforts; therefore, focused monitoring that is clearly linked to decision-making is necessary to continually refine and adjust management strategies.

Postcopulatory sexual selection plays an important role in the reproductive success of males in many species. Differences in fertilization success could affect rates of admixture and genetic introgression between divergent lineages. We investigated sperm precedence in matings in captivity involving Common quails (Coturnix coturnix) and farm quails of hybrid origin (C. coturnix × domestic Japanese quail, C. japonica), the last used in restocking practices to increase hunting bags. These inter-specific matings in natural conditions are claimed to represent an important threat to the conservation of native Common quail populations. Results showed that fertilization success of each male depended on (1) the time it spent with the female, (2) the presence of sperm from a previous male in the female oviduct, (3) the time that the previous partner had been copulating with the female, and, most importantly, (4) the genetic origin of the male (wild or farm). Farm hybrid males showed higher fertilization success than wild Common males, and they required less time with the female to fertilize the same proportion of eggs. The presence of sperm from another male in the female oviduct reduced the percentage of fertilized eggs by a male. However, this reduction was higher for wild males when the precedent mate was a farm male. In summary, the sperm of farm hybrid males may outcompete the sperm of native males and this could be favoring the introgression of domestic Japanese alleles into the Common quail population, thus constituting a severe conservation threat to wild Common quail populations., [GER]In vielen Arten spielt die postkopulative sexuelle Selektion für den Fortpflanzungserfolg von Männchen eine große Rolle. Unterschiede im Befruchtungserfolg können Einfluss haben auf die Rate der genetische Introgression und Vermischung zwischen verschiedenen Abstammungslinien. Um Unterschiede in der Spermienwettbewerbsstärke zwischen wilden Wachteln (Coturnix coturnix) und Japanischen Wirtschaftswachtelaus stammenden Hybridwachteln (C. coturnix × C. japonica), die für die Aufstockung von Beständen zur Jagd genutzt wurden, zu untersuchen, haben wir Verpaarungen in der Gefangenschaft durchgeführt. Es wird vermutet, dass solche zwischenartlichen Verpaarungen unter natürlichen Bedingungen ein Risiko für den Erhalt des Artbestandes von Wachteln darstellen. Unsere Ergebnisse zeigten, dass der Fortpflanzungserfolg eines Männchen davon beeinflusst wurde (1) wie viel Zeit es mit dem Weibchen verbrachte, (2) ob bereits Spermien eines anderen Männchen im Ovidukt waren, (3) wie lange ein vorheriger Partner mit dem Weibchen kopuliert hatte, und vor allem (4) welchen genetischen Hintergrund das Männchen (Wildtier oder Wirtschaftswachtel) hatte. Hybride Wirtschaftswachteln hatten den höchsten Fortpflanzungserfolg und befruchteten die gleiche Anzahl Eier eines Weibchens schneller. Wenn bereits Spermien eines anderen Männchens im Ovidukt waren, verringerte dies den prozentualen Anteil erfolgreicher Befruchtungen des nächsten Männchen. Dieser Effekt war am stärksten für wilde Männchen, wenn der vorherige Partner eine Wirtschaftswachtel war. Zusammenfassend lässt sich sagen, dass Spermien von Hybridmännchen wettbewerbsstärker zu sein scheinen als Spermien frei lebender Wachteln. Dies mag die Introgression der Allele von Japanischen Wirtschaftswachteln in die Wildpopulation unterstützen und eine ernste Bedrohung für den Erhalt wilder Wachtelpopulationen darstellen.

Behavioural studies comparing hatchery and wild-caught fish are useful to improve selection for aquaculture and restocking programmes. We examined swimming behaviour characteristics in wild captured and domesticated sea bass juveniles before and after eliciting a startle response at 8 different ages and always on naive individuals. We specifically investigated whether domestication impacts juvenile sea bass behaviour and whether the first months of captivity induce behavioural modifications in wild juveniles. An apparatus was designed to mimic a predator attack by presenting a sudden visual and mechanical stimuli simultaneously in 8 arenas where single individuals were placed and video recorded. The reactivity response was evaluated and different swimming variables including angular velocity, total distance travelled, mean velocity, immobility and distance from stimulus point were analysed from videos taken 5 min before stimulus actuation, 5 and 15 min after. Otolith readings showed that wild and domesticated juveniles were of similar age (similar to 55 days at the start of the experiment and similar to 125 at the end of experiment). There were consistent behavioural differences (e.g. higher angular velocity and distance from stimulus point in wild fish) demonstrating that domestication reduces flight response behaviour. There were also similarities between both fish origins (similar response to stimulus actuation: decrease of total distance travelled and mean velocity, increase of angular velocity and immobility). A decrease over time in reactivity and variability in swimming responses among fish of both origins showed that captivity only does not fully explain wild fish behaviour changes and ontogenic modifications are likely interplaying. (C) 2012 Elsevier B.V. All rights reserved.

WOS: 000409636200014 Turkey has, with geographic location including Istanbul and Canakkale straits the system, 178,000 km in length streams, 906,000 ha of natural lakes, and 411,800 ha of dam lakes, and 28,000 ha of ponds due to richness inland waters which include freshwater fish. The fingerling fish (fry) were restocked approximately 250,000,000 in natural lakes, dam lakes and ponds for fisheries between years of 1979 and 2005. Canakkale has rich freshwater potential with 7 major rivers (Buyukdere, Karamenderes stream, Kavak brook, Kocacay stream, Saricay stream, Tuzla brook, Umurbey brook), 7 Dam Lakes (Atikhisar, Zeytinlikoy, Bayramic, Bakacak, Tayfur, Umurbey and Yenice-Gonen Dam lakes). In the studies, it has been determined that 15 fish species belonging to 6 families (Anguillidae, Atherinidae, Salmonidae, Cobitidae, Cyprinidae and Poecilidae) can be found in reservoirs. Fish restocking of the activities of the reservoir until today approximately 1,120,000 (Cyprinus carpio L., 1758) is introduced. In this study, the activity of Canakkale province in the fish restocking and reservoir exploiting possibilities were discussed in view of reservoir fisheries potential which is used insufficiently today.

In this study, the effect of shelter acclimation on the post-release movement and putative predation mortality of hatchery-reared black-spot tuskfish Choerodon schoenleinii was examined using acoustic telemetry. We acclimated four 1-year-old fish to shelters in cages before release and compared their movements with six nonacclimated fish. Since it was not possible to compare the behavioral pattern between the former and the latter fish due to the short periods the latter fish were available to be monitored, we also compared their movements with those of large nonacclimated fish that were less likely to be preyed upon. Sixty-seven percent of the nonacclimated fish showed atypical movements before the signals ceased to be detected, a pattern that suggested a predation event had occurred, whereas none of the acclimated and large nonacclimated fish showed the atypical movements. In addition, the probability of detection cessation was about 13 times lower in the acclimated than nonacclimated fish. The signal detection patterns suggest that the acclimated fish utilized night-time shelters from the first night after release, while the large nonacclimated fish started to utilize shelters several days after release. Therefore, it is likely that the shelter acclimation enhanced the shelter utilization by tuskfish, possibly decreasing post-release predation mortality., Fisheries Science, 77(3), pp.345-355; 2011

Multiple geographical regions have been proposed for the domestication of Equus caballus. It has been suggested, based on zooarchaeological and genetic analyses that wild horses from the Iberian Peninsula were involved in the process, and the overrepresentation of mitochondrial D1 cluster in modern Iberian horses supports this suggestion. To test this hypothesis, we analysed mitochondrial DNA from 22 ancient Iberian horse remains belonging to the Neolithic, the Bronze Age and the Middle Ages, against previously published sequences. Only the medieval Iberian sequence appeared in the D1 group. Neolithic and Bronze Age sequences grouped in other clusters, one of which (Lusitano group C) is exclusively represented by modern horses of Iberian origin. Moreover, Bronze Age Iberian sequences displayed the lowest nucleotide diversity values when compared with modern horses, ancient wild horses and other ancient domesticates using nonparametric bootstrapping analyses. We conclude that the excessive clustering of Bronze Age horses in the Lusitano group C, the observed nucleotide diversity and the local continuity from wild Neolithic Iberian to modern Iberian horses, could be explained by the use of local wild mares during an early Iberian domestication or restocking event, whereas the D1 group probably was introduced into Iberia in later historical times.

The goal of the present study was to determine the most appropriate time to release the immatures of Ucides cordatus (Linnaeus) produced in the laboratory into the natural environments. Specifically, the time when the megalopae sought the mangrove sediment to excavate the burrows was determined, as well as the time necessary for their metamorphosis into the first juvenile stage. Results indicated that the megalopae of U. cordatus reared in the laboratory took three to ten days (median = 6) after their molt to excavated burrows in the sediment. The average time for the megalopae to molt into juveniles was 12.6 days (SD = 2.3).O estágio de desenvolvimento em que se encontram as formas jovens de caranguejo produzidas em laboratório, no momento da sua liberação para o ambiente, é um fator chave para o sucesso dos trabalhos de repovoamento. O presente trabalho teve como objetivo determinar a idade mais adequada das formas jovens de U. cordatus, produzidas em laboratório, para sua liberação no ambiente natural. Especificamente, o momento em que as megalopas procuram o sedimento de mangue para escavar tocas foi determinado, assim como o tempo que demoram até realizarem a metamorfose para o primeiro estágio juvenil. O experimento indicou que as megalopas de U. cordatus produzidas em laboratório levam de 3 a 10 dias (mediana = 6) após a metamorfose até escavarem tocas no sedimento. O tempo médio que as megalopas levaram até realizar a metamorfose para o primeiro estágio juvenil foi de 12,6 dias (desvio padrão = 2,33).

This study compared the reproductive and growth performances of pigs before and after depopulation and restocking after a foot-and-mouth disease outbreak in Japan. Data for the time period before and after depopulation and restocking were obtained from three farrow-to-finish farms. As a result of depopulation and restocking, hygiene levels were improved, and common infectious diseases, such as porcine reproductive and respiratory syndrome and Aujeszky's disease, remained undetected on the farms. Compared with before depopulation, reproductive and growth performances improved after depopulation; the number of total pigs born was higher, the postweaning mortality rate was lower, and the age at slaughter was lower (P

© 2015, Springer-Verlag Berlin Heidelberg. The use of restocking of animals is common practice in the management of populations subject to hunting or recreational fishing. This practice encompasses the release of large numbers of individuals in an area where the species already exists, and thus it can have detrimental genetic impacts on the target populations, especially when captive-reared animals are involved. To better understand this practice and its conservation implications, we chose as a model the wild rabbit (Oryctolagus cuniculus), a species of high economic and ecological importance, and often under intense management for hunting or conservation purposes, particularly after the large decline caused by rabbit hemorrhagic disease in the 90′s. We studied the genetics of rabbit populations in an area where restocking with captive, wild–domestic hybrids was common. We collected a total of 503 samples from 15 hunting estates that had experienced differing restocking levels, as well as from five locations with no historical restocking and five game farms. All samples were analyzed to determine the mitochondrial DNA (mtDNA) lineage typical of the two European wild rabbit subspecies and domestic rabbit. Game farms and never restocked populations were very different in their haplotypic composition. In restocked areas, the proportion of the domestic lineage was higher when releases were recent and repeated, but this declined rapidly over time, in part due to selective removal by hunting. The extended use of this practice, considering the pronounced genetic and genotypic differences between domestic and wild rabbits, represents a potential danger to natural populations, especially given the marked decrease in wild rabbit numbers experienced in recent years in its original distribution range.

An attempt was made to extend the area of distribution of a native population of brown trout Salmo trutta belonging to a Mediterranean lineage (ML), which has maintained itself in the Dranse d’Abondance, a fast-flowing alpine stream (Haute-Savoie, France), despite several decades of intensive restocking with brown trout derived from the Atlantic lineage (AL). This was done by releasing an ML component into the predominantly AL population still present on the Ugine, the main tributary of the Dranse d’Abondance. This strategy of rehabilitation restocking was tested using fluoro-marked juveniles produced from a captive breeding stock derived from the wild Dranse d’Abondance ML stock. Samples of 0þ year fish were collected over the period 1995–2003 in order to assess the impact of the restocking. Percentages of fluoromarked otoliths revealed significant contributions of ML restocking in the 0þ year autumnal standing population, with levels ranging from 34� 3t o 61� 4%. The change in the genetic characteristics of the 0þ year population produced by natural recruitment was monitored by analysing the unmarked subjects. Frequencies observed at two microsatellite loci revealed a considerable rise (from 0 to 60%) in the level of Mediterranean alleles in the natural 0þ year population since the introduction of restocking using ML individuals. # 2006 The Authors Journal compilation # 2006 The Fisheries Society of the British Isles

Habitat use by stocked and native brown trout (Salmo trutta L.) was assessed in two headwater streams of North-eastern Portugal. Underwater observations were made during the summer season in three successive years to evaluate the effect of supplemental trout stocking. Multivariate analysis techniques applied to data sets on microhabitat use were exploited to identify the focal elevation (distance of fish from the bottom), total depth and cover as the variables that contribute most to the discrimination between stocked and native trout. Preference curves computed for native and stocked trout of the same age (1+), showed a distinct pattern in their ability to explore the available microhabitat resources. Stocked trout tended to occupy deeper pools (total depth > 100 cm vs. 60-100 cm for native trout), holding higher focal elevations (140-160 cm vs. < 20 cm for native) with lower water column velocities (< 10 cm.s-1 vs. 10-20 cm.s-1 for native) and no specific preference for cover. In contrast, native trout displayed a clear preference for microhabitats with coarse substrate (particle size > 22.5 cm) and cover (combination of boulders and overhanging vegetation or undercut banks). Furthermore, a high poststocking movement of 80% hatchery-reared fish was verified just one month after their release, suggesting that stocking did not contribute to the sustainable populations in either stream, and is far from being an adequate management technique.

After the first spread of crayfish plague (aphanomycosis) at the end of the nineteenth century, the formerly abundant populations of native crayfish in Poland declined drastically. Analysis of historical data on the occurrence and distribution of crayfish in Poland led to the conclusion that without human intervention the native crayfish species would be at high risk of being made extinct. The largest programme concerning crayfish monitoring and restocking in Poland was “Active protection of native crayfish in Poland” conducted by the Inland Fisheries Institute, the Department of Ecology, University of Szczecin, the Department of Zoology, Warsaw Agricultural University and the University of Warmia and Mazury that was funded by the EkoFundusz Foundation and Inland Fisheries Institute in 1999-2001. One of the main objectives and results of this programme was the determination of indigenous crayfish distribution in Poland (mainly Astacus astacus and Astacus leptodactylus) and the restocking of suitable habitats with indigenous crayfish. The densest populations (> 2 500 adult individuals per hectare) were used as a source of restocking material. Restocking was performed in 54 water bodies using a total of 45 200 individuals of A. astacus and 9 800 of A. leptodactylus. Between 2001-2002, the success of the restocking programme was monitored. According to the results obtained so far, the restocking exercise has been successful in at least 60.8% of the cases.

Irish white-clawed crayfish stocks show high genetic uniformity between systems, although individual populations usually show good heterozygosity. The inference is that they were derived from a single immigrating stock, related to those in Western France. Irish crayfish stocks occur widely and often in good numbers in lakes and streams; they are protected and rarely fished, and there are no alien species. Their use for reintroduction into depleted areas within Ireland, including Special Areas of Conservation, is examined. Irish crayfish also have potential value for restocking depleted continental locations, under stringent conditions of environmental suitability and genetic conformity.

The present paper summarizes the outcome of a roundtable discussion on reintroductions or restocking as a management strategy for native European crayfish, which took place during the European Crayfish conference in Poitiers, France in September 2001. Aspects related to the suitability of the target habitat, the stocking material and the stocking procedure itself are important to consider during any reintroduction measure: Apart from general water quality and structural parameters, a suitable habitat is ideally geographically isolated from other surface waters and human activities such as intensive fishing pressure. However, it is of striking importance to make sure that the target habitat is free of crayfish plague, e.g. by experimental in situ exposure of native specimens. Overexploitation should be avoided if the stocking material originates from other surface waters and genetic aspects should be considered in stocking material originating from both natural surface waters and crayfish farms. Information for the stocking procedure itself are summarized from experiences gathered in various European countries. As an overall result of the discussion, the following three key questions related to reintroductions of native crayfish arised: 1. Why are the native crayfish not present (anymore) in the target habitat? 2. Do native crayfish survive in situ exposure as a test for crayfish plague? 3. Is the reintroduction or restocking measure successful in establishing a self-sustaining stock of native crayfish?

Interbreeding of two species in the wild implies introgression of alleles from one species into the other only when admixed individuals survive and successfully backcross with the parental species. Consequently, estimating the proportion of first generation hybrids in a population may not inform about the evolutionary impact of hybridization. Samples obtained over a long time span may offer a more accurate view of the spreading of introgressed alleles in a species' gene pool. Common quail (Coturnix coturnix) populations in Europe have been restocked extensively with farm quails of hybrid origin (crosses with Japanese quails, C. japonica). We genetically monitored a common quail population over 15 years to investigate whether genetic introgression is occurring and used simulations to investigate our power to detect it. Our results revealed that some introgression has occurred, but we did not observe a significant increase over time in the proportion of admixed individuals. However, simulations showed that the degree of admixture may be larger than anticipated due to the limited power of analyses over a short time span, and that observed data was compatible with a low rate of introgression, probably resulting from reduced fitness of admixed individuals. Simulations predicted this could result in extensive admixture in the near future

The release of farm-reared game is considered a conflictive management tool because of its potential harmful ecological effects on wildlife and associated habitats. Estimates of the number of animals released and the area where this game management takes place could give an idea of the magnitude of their potential impacts. We aimed to quantitatively assess the release of farm-reared red-legged partridges (Alectoris rufa) in the province of Ciudad Real, central Spain, one of the main hunting areas in this country. We analysed the official permits that the regional government granted to the hunting estates to release farm-reared partridges between 2006 and 2012. Our results show that an average of 800,000 partridges were released annually in the study area. A decrease in the number of hunting estates that used this game management practice, as well as in the number of red-legged partridges officially released, was observed during the last years within the study period. This might be a consequence of the current economic crisis, rather than a change in management styles. Release intensity was spatially heterogeneous, being higher in the southeast of the study area, where historically red-legged partridge was more abundant. Most of the red-legged partridges released came from only four farms placed in northern Spain. Our results suggest that this management activity should be better monitored and that spatial regulations should also be considered., Work was supported by the European Commission (7th Framework Programme for R&D through project HUNT, 212160, FP7-ENV-2007-1) and by CSIC (PIE 201330E105).

International audience; The genetic impact of restocking Mediterranean brown trout populations with hatchery stocks was investigated in the Orb River drainage (France), using genetic data from three microsatellite loci. We sampled two wild populations, the main river which is restocked each year and one of its tributaries which has not been restocked for 6 years. Each sample was divided into two age groups (juveniles/ adults). Introgression of each native population by hatchery stocks was previously estimated using allele frequencies from two diagnostic protein-coding loci and one mtDNA haplotype. The genetic structure and allelic frequency at three microsatellite loci in native populations were compared with two hatchery samples belonging to stocks usually used for restocking this drainage. High levels of polymorphism (23±27 alleles per locus) were detected for two loci, whereas the third was less polymorphic. Polymorphism was signi®cantly higher in the restocked population than in the now undisturbed population. Signi®cant dierences between age groups were observed in the main river, but not in its tributary. The introgression estimates using microsatellites were compared to those obtained from proteins and mtDNA. The dierent possible origins of alleles common to hatcheries and wild populations (homoplasy, ancestral polymorphism or introgression) are discussed.

Population genetic structure of Vimba vimba persa was investigated using microsatellite markers from 4 regions along the Iranian coastline of Southern the Caspian Sea (Anzali lagoon & havigh River in Gilan province, BabolRoud River in Maz&eran province & GorganRoud River in Golestan province). Genomic DNA from 121 specimens was extracted from fin tissue by phenol-Chlorophorm method & PCR reaction was accomplished with 17 microsatellite primers, out of 17 microsatellite primers 14 loci were amplified, in which 10 of them were amplified with reasonable polymorphism & 4 were monomorphism. Totally 302 alleles were identified on average 7.5 Observed & expected heterozygosity averages were 0.80 & 0.77 respectively. Most cases significantly deviated from Hardy-Weinberg equilibrium (p 0.01). The estimation of Fst (p 0.01) revealed significant population structuring & estimate four population of Vimba vimba persa is identified in the Caspian Sea. These studies were to apply & develop population genetic approaches to assist conservation, sustainable harvest & restocking of these populations.

A round table discussion involving 25 researchers from 11 European countries was organized during the congress “European Crayfish: food, flagships and ecosystem services” (held in Poitiers, France, 26–29th October 2010) to consider current activities dealing with management of indigenous crayfish species (ICS) with special regards to their culture, restocking and conservation strategy. In the following opinion paper, we attempt to summarize best practice of current conservation strategy as well as advantages and disadvantages of applied tools and approaches for listed species or species complexes. The development of conceptual models for the protection of ICS in Europe seems to be necessary; however, currently recommended approaches of conservation strategy of ICS differ according to countries and species. The different approaches to conservation of Astacus astacus and species in the genus Austropotamobius, such as genetic diversity, captive breeding, origin and characteristics of stocking material and establishment, as well as long-term objectives of sanctuary or “ark” sites, were highlighted during the round table discussion.

Rabbit restocking is widely used in Spain for conservation and/or hunting purposes; however, the success of rabbit restocking is generally low. Thus, many studies have assessed ways to reduce this problem, one of which is the use of a ¿soft-release¿ procedure whereby rabbits are acclimated to their release site for a variable time period prior to release. This study assessed the short-term effects of two soft-release confinement periods on the survival of rabbits during an experimental restocking program carried out in southwest Spain. The post-release survival rate of rabbits confined at the release site for six nights was significantly higher than that of rabbits confined for three nights. The longer acclimation period after rabbit translocation minimized mortality while rabbits adapted to their new environment., C. Rouco was supported by a postdoctoral grant from the regional government of Castilla-La Mancha (JCCM), and the European Social Fund. Funding was provided by the projects by Confederación Hidrográfica del Guadalquivir, by the Projects CGL2005-02340/BOS, FAU2006-0014-C-02-02, PAI06-170, and PREG-05-022.

International audience; The genetic variability of 11 French pike Esox lucius populations from rivers or extensive aquaculture ponds was analysed using seven microsatellite markers. The fish stocking of eastern European pike in French rivers is widespread, so five supplementary populations from this region were also analysed. Genetic variability within the French population was small, and similar to that previously found in Europe for this species. French populations from stocked rivers and extensive farms formed a genetically homogeneous group, and did not diverge from most eastern European samples, which may reflect either ancestral polymorphism or a complete introgression of French populations by introduced stocks. Bayesian analysis of the admixture between populations enabled identification of the French populations that were likely to be affected by introduced stocks (of local or foreign origin). Three genetically distinct evolutionary branches were identified: continental Europe, Danube basin, and south-western France. The last is a new finding in the species which needs to be further explored by comparisons with wild populations at other sites.

The release of hatchery-reared fishes for restoring threatened and endangered populations is one of the most controversial issues in applied ecology. A central issue has been to determine whether releases cause extinction of local wild populations. This may arise either through domesticated or non-local fishes hybridizing with wild fishes, or through inappropriate behavioural interactions; for example, many hatchery fishes show exaggerated aggressive and competitive behaviour and out-compete wild counterparts. The impact of the impoverished hatchery environment in shaping behaviour is only now receiving attention. Attempts to counteract hatchery-related behavioural deficiencies have utilized intensive training programmes shortly before the fishes are released. However, we show here that simple exposure to variable spatial and foraging cues in the standard hatchery environment generates fishes with enhanced behavioural traits that are probably associated with improved survival in the wild. It appears that fishes need to experience a varying and changeable environment to learn and develop flexible behaviour. Using variable hatchery rearing environments to generate suitable phenotypes in combination with a knowledge of appropriate local genotypes, rehabilitation of wild fishes is likely to succeed, where to date it has largely failed.

Une méthode de production de populations de truites fario présentant une forte variabilité génétique est proposée pour les repeuplements de restauration. Du sperme de géniteurs sauvage est conservé à des températures voisines de 0° C et à l'obscurité, pendant la durée du transport entre le cours d'eau d'origine et la pisciculture, où l'on procède à l'insémination d'ovules de truites fario d'élevage en utilisant le dilueur de sperme 532. La descendance est destinée de préférence aux déversements au stade oeuf dans le milieu préalablement restauré.

The effects of temperature and salinity on the survival and development of larval Metapenaeus dalli were investigated in two experiments. First, the effects of four temperatures of 22.6, 25.8, 29.4 and 32.6 °C on survival and development time were examined from the Nauplius VI to the Mysis I sub-stage. Survival was significantly lower at 32.6 °C than at 22.6 and 25.8 °C. Development times differed significantly across all temperatures, decreasing linearly with temperature from 161.5 h at 22.6 °C to 74.8 h at 29.4 °C then decreased slightly to 71.4 h at 32.6 °C. Second, the combined effects of three temperatures (21.4, 26.5 and 29.7 °C) and three salinities (30, 35 and 40‰) on survival and development were quantified over a 48 h period from the Nauplius VI sub-stage. Only salinity was found to influence survival, with peak survival (77.7%) found to occur at the control salinity (~35‰). Any increase or decrease in salinity from this value resulted in a decrease in survival, with the lowest salinity tested (30‰) having a significantly negative effect on survival (58.4%) when compared to the control. Only temperature was found to influence the rate of development, with significant increases in development index values being recorded as temperature increased. The recommended conditions for optimal survival and development of M. dalli larvae as determined by this study are, therefore, 25.8 °C and 35‰.

A series of experiments was conducted to test if keeping hatchery-produced European lobster juveniles ( Homarus gammarus ) in an enriched environment with substrate and shelter would improve anti-predator behaviour and survival in a competition setting. Newly hatched postlarvae (stage IV) were divided into two treatments. Naive postlarvae were raised in single compartments, while trained postlarvae were released communally into tanks with substrate and shelter, allowing for developing burrowing and shelter-seeking behaviour and interactions with conspecifics. The duration of the treatment lasted 181 days in 2007/2008 and 226 days in 2008/2009. In the second experiment, 4-mo old juveniles were purchased from a commercial hatchery and divided into the same two treatment groups. The treatments were considerably shorter, lasting 47 days. At the end of the treatment period an equal number of juveniles from each treatment was released into experimental units with substrate and shelter i.e. semi-natural system for a period of 91–145 days. Number of shelters was half the total number of juveniles to induce competition for shelters. In both experiments, trained juveniles occupied more shelters and had higher survival than naive juveniles. Combining all experiments, average survival was 53% in trained lobsters compared with 18% in the naive lobsters. These results are the first to demonstrate that enriching the hatchery environment for a period of time (a minimum of 47 days here) while rearing European lobster juveniles increased their shelter occupancy and their survival compared to naive juveniles the same size and age. Survival rates were 3–4 times higher in trained compared to naive lobsters after 145 days.