Hatchery Stocks Research Articles

Rainbow trout adaptation to a warmer Patagonia and its potential to increase temperature tolerance in cultured stocks

The viability of rainbow trout Oncorhynchus mykiss (Walbaum, 1792) culture is being challenged progressively by global warming. Previous trials with Australian and Japanese rainbow trout lines suggested that improvements in thermal performance may be possible. Here, we hypothesized that strain-related differences in physiological response to temperature exist between a north Patagonian hatchery stock (CENSALBA), a Neotropical one (Criadero Boca de Río), and a thermal stream (Valcheta) population of wild introduced rainbow trout. This was tested by comparing, at 20°C, the thermal preference, specific metabolic rate, thermal tolerance, growth, and condition on juveniles of the three strains, and on a Valcheta stream male x CENSALBA female F1 cross. Preferred temperature (PT) and loss of equilibrium temperature (LET, a measure of thermal tolerance) of Valcheta stream and F1 were significantly higher than those of CENSALBA, and the average PTs of Valcheta stream and F1 were higher than the 95% confidence interval of available reference data for rainbow trout. These results suggest that the F1, reared under standard hatchery conditions and selected by growth and thermal preference, presents higher thermal preference and higher thermal tolerance than the current CENSALBA hatchery stock. Introduction of this naturally adapted strain to hatchery stocks would likely result in the improvement of their temperature resistance to warmer waters. Current studies on adults of this F1 generation are underway.

Landmark-based Morphometric and Meristic Variations of Endangered Mrigal Carp, Cirrhinus cirrhosus (Bloch 1795), from Wild and Hatchery Stocks

Wild stocks of endangered mrigal carp, Cirrhinus cirrhosus (Bloch 1795), continues to decline rapidly in the Indo-Ganges river basin. With an objective to evaluate its population status, landmark-based morphometric and meristic variations among three different stocks viz., hatchery (Jessore), baor (Gopalganj) and river (Faridpur) in Bangladesh were studied. Significant differences were observed in 10 of the 15 morphometric measurements viz., head length, standard length, fork length, length of base of spinous, pre-orbital length, eye length, post-orbital length, length of upper jaw, height of pelvic fin and barbel length, two of the 8 meristic counts viz., scales above the lateral line and pectoral fin rays and 10 of the 22 truss network measurements viz., 1 to 10, 2 to 3, 2 to 8, 2 to 9, 2 to 10, 3 to 4, 3 to 8, 4 to 5, 4 to 7 and 9 to 10 among the stocks. For morphometric and landmark measurements, the 1st discriminant function (DF) accounted for 58.1% and the 2nd DF accounted for 41.9% of the among-group variability. In discriminant space, the river stock was isolated from the other two stocks. On the other hand, baor and hatchery stocks formed a very compact cluster. A dendrogram based on the hierarchical cluster analysis using morphometric and truss distance data placed the hatchery and baor in one cluster and the river in another cluster and the distance between the river and hatchery populations was the highest. Morphological differences among stocks are expected, because of their geographical isolation and their origin from different ancestors. The baseline information derived from the present study would be useful for genetic studies and in the assessment of environmental impacts on C. cirrhosus populations in Bangladesh.

Spatial and Temporal Segregation of Wild and Hatchery Winter Steelhead Populations in Eagle Creek, Oregon

AbstractA segregated hatchery program promotes conservation by limiting the amount of overlap in return timing and spawning locations of hatchery‐ and natural‐origin fish. The objective of the present study was to use radiotelemetry data collected from 2005 to 2007 to better understand the level of spatial and temporal segregation between hatchery and natural‐origin steelhead Oncorhynchus mykiss in the Eagle Creek basin, Oregon. The analysis resulted in three key findings. First, hatchery‐origin winter steelhead were unlikely to migrate into the North Fork Eagle Creek, a tributary that has historically lacked any hatchery releases or influence, suggesting a high level of segregation from the natural‐origin population returning to that stream. Second, hatchery fish arrived at the lower fish ladder on Eagle Creek and at Eagle Creek National Fish Hatchery (NFH) earlier than natural‐origin fish, suggesting that broodstock management practices to maintain an early returning hatchery stock (i.e., temporal segregation) have been somewhat successful. Finally, regardless of the differential arrival timing to Eagle Creek NFH, there is evidence of an increased probability of spatial and temporal overlap of the populations as the return progresses, and this may be explained by successful reproduction of hatchery‐origin fish in main‐stem Eagle Creek. Integrated and segregated hatchery programs should be monitored periodically to ensure that they are meeting their stated goals.Received October 12, 2016; accepted March 14, 2017 Published online May 4, 2017

Mitochondrial DNA variation and population genetic structure in the small yellow croaker at the coast of Yellow Sea and East China Sea

Small yellow croaker is one of the most important fishery species in China. The mass–scale artificial propagation of this fish species was initially developed in 2015 with the aim of facilitating the fish production stock enhancement and aquaculture programs in the future. In the present study, the wild broodfish and its corresponding progeny along with three other wild populations were sampled and subjected to sequence analysis of the mitochondrial cytochrome c oxidase subunit I gene. The genetic diversity and population genetic structure were evaluated with a total sample size of 141 individuals representing the populations of the Yellow Sea (Qingdao and Lvsi populations) and the East China Sea (Xiangshan and Ningde populations). The wild populations were characterized by high haplotype diversity (0.925–0.976) and low nucleotide diversity (0.376%–0.560%). The hierarchical analysis of molecular variance (AMOVA) analysis and the values of pairwise Ф-statistics (ФST) indicated non-significant genetic differentiation among the four wild populations. The hatchery stock XSH exhibited lower indices of genetic diversity compared with the wild populations that could be attributed to the small effective population size. The findings of the present study have valuable insight to the sustainable management and utilization of this resource.

Microsatellite assessment of the genetic diversity in indigenous populations of curimba (Prochilodus argenteus) in the São Francisco river (Brazil)

The freshwater fish curimba (Prochilodus argenteus) is an endemic species of the Sao Francisco River basin, with great aquaculture potential. The construction of several hydroelectric power dams along the river, and the pulsed releases of water from these dams altered and degraded the native fish habitats, which led to the development of a hatchery-reared fingerling restocking program. A comprehensive genetic baseline evaluation of the indigenous populations of curimba and of a hatchery stock was done using microsatellite markers. Pairwise F ST values, Bayesian analysis and the number of migrants per generation were used to illustrate the genetic structure of the curimba populations along almost 3000 km of the river, suggesting the existence of three units of conservation: one in the Upper, a second in the Middle and a third including part of the Middle, Submiddle and Lower stretches. We have analyzed the genetic contribution of hatchery stock releases in two stretches of the river using individual admixture coefficients; and the results showed that admixture makes a negligible contribution to indigenous recruitment. We discussed about supplementation programs for this river from the perspective of three units of conservation and the risks associated with using domesticated fish.

Population genetic structure in European lobsters: implications for connectivity, diversity and hatchery stocking

Population genetic structure in European lobsters: implications for connectivity, diversity and hatchery stocking

Genetic variation in wild and hatchery population of Catla catla (Hamilton, 1822) analyzed through mtDNA cytochrome b region

Catla (Catla catla) is a one of the most harvested Indian major carps and is widely cultured fish species in Indian subcontinent. In the present study, genetic variability between hatchery and wild stocks of Catla was surveyed using sequence data of mitochondrial DNA of partial 307 bp of cytochrome b region. A total of 174 Catla individuals were examined from three different river basins and hatcheries. Significant genetic heterogeneity was observed for the sequence data (FST = 0.308, p ≤ 0.001). However, analysis of molecular variance (AMOVA) resulted in insignificant genetic differentiation among the samples of three rivers and culture zones (FCT = −0.10, p = 0.44). The result suggested a significant genetic variation within different riverine system, low genetic differentiation among samples from river basins and a lack of genetic variation in hatchery populations.

Genetic Structure of Different Cultured Populations of the Pacific AbaloneHaliotis discus hannaiIno Inferred from Microsatellite Markers

ABSTRACT Pacific abalone Haliotis discus hannai is one of the most important species of shellfish aquaculture. The annual production of cultured abalone exceeded 100,000 t in 2013, and the Pacific abalone was the main farmed species. The genetic diversity of hatchery stocks of H. discus hannai in most areas of China, however, remains unknown. The exchange of Pacific abalone in China was not only among hatcheries but also between southern and northern areas, and the Japanese population was widely used for the production of seed. Both practices may have led to the production of mixed seeds, and the difference between populations may be not significant, which could result in inbreeding and loss of potentially valuable alleles. Therefore, it is necessary to assess the current genetic characterization of hatchery populations. For the analysis, a total of 10 populations were obtained from different hatcheries: Dalian, Qingdao, and Changdao in the northern coastal areas; and Xiapu, Lianjiang, Putian, Zhangpu, Ji...

Inter-annual variation in the surplus prey production for stocking of Japanese flounder Paralichthys olivaceus

Stocking hatchery fish into the wild should only be implemented at a level that can be sustained within the available food-based carrying capacity to avoid food resource competition with wild conspecifics. We constructed a simulation model to assess the growth of wild conspecifics under different magnitudes of hatchery fish releases, including no releases and actual release levels, and under different wild fish abundancies. Stocking of juvenile Japanese flounder Paralichthys olivaceus (approximately 70–110mm TL) in Fukushima from 2003 to 2005 was analyzed. We monitored post-release changes in abundance of both cultured and wild juveniles and their prey (mysids). Our survey and modelled simulations revealed that the surplus prey production was sufficient to support the consumption of stocked and wild Japanese flounder (up to 150,000 individuals per site in 2003 and 2004), during which wild juveniles achieved nearly maximum growth rates. However, in 2005, during which a dominant year class of wild Japanese flounder occurred, the body size of wild juveniles was 49% smaller than the predicted size based on the maximum growth rates. This suggests that the food-based carrying capacity was reached in that year. Thus, it is important to evaluate the existing prey and wild juveniles levels and adjust the release accordingly every year.

Growth, survival and interspecific social learning in the first hatchery generation of Eurasian perch (Perca fluviatilis)

New insights into present-day cultivation practices are needed when new species are taken into aquaculture. Understanding different features of survival selection operating on wild fish in artificial hatchery environment is topical also in the contexts of fish conservation and reintroduction programs. We used wild Eurasian perch (Perca fluviatilis) to produce the first generation hatchery stock, and studied survival and growth of the offspring at the age of two years through the transition from a seminatural pond to the hatchery, and the first growth season in the tank environment. First, we tested whether hatchery-raised brown trout (Salmo trutta) could be used as tutors for tank-naïve perch in training to accept commercial dry feeds, and thereby increase survival and growth of the perch in tank culture. Second, we tested whether supplementing the dry feed with minced prey fish would increase perch survival and enable faster growth compared to dry feed diet only. The brown trout tutors did not increase survival or growth of tank-naïve perch, but both improved markedly if the perch were habituated to tank culture conditions already during cold-water seasons. Survival and consequent biomass gain were the highest when the pre-habituated perch were on the fish-supplemented dry feed diet. Survival on the fish-supplemented diet was significantly higher (73.1%) compared with the survival on the dry feed diet (44.4%). The perch exhibited bimodality in final size distribution in both experiments. Although the mean body size of the fast-growing perch did not depend on the diet, the total biomass gain during the first growth season was substantially higher on the fish-supplemented diet (+104%) than on the dry feed diet (+41%). The difference was mainly due to higher survival of the large perch on the fish-supplemented diet but also because the fish supplement supported significant growth among the small fish. To conclude, commercial feeds may exert a strong survival selection on wild fish in hatcheries, which can be mitigated by adding natural elements to the diet. Although perch ability to copy the feeding behaviour from interspecific tutors was negligible for large-scale aquaculture purposes, our experiment encourages further studies on the potential of inter- and intraspecific social learning in the context of feed training in aquaculture. Statement of relevanceAccording to this study, high mortality in perch aquaculture can be reduced by supplementing commercial dry feed diet with minced, less valuable prey fish.

Association of clonal diversity and population growth in the small-type rotifer Brachionus koreanus during hatchery mass production

In this study, we identify clones of S-type rotifers Brachionus koreanus based on haplotypes of mitochondrial gene cytochrome c oxidase subunit I (mtCOI) and microsatellite DNA genotypes. We then study how clonal diversity affects the population growth of rotifers in a mass culture at a hatchery using a lot of B. koreanus rotifers for analysis. Microsatellite DNA markers were also developed to identify clones of B. koreanus. Clones of B. koreanus were identified based on haplotypes of mtCOI, microsatellite genotypes, as well as a combination of these haplotypes and genotypes. Three haplotypes of mtCOI, three clones based on microsatellites, and six clones based on a combination of mtCOI haplotypes and microsatellite genotypes were identified. The population growth rate of mass-cultured rotifers was monitored for a month, and the correlation between population growth rate and these clonal diversities was analyzed. Observed was a significant positive correlation between the population growth rate and haplotype diversity (r=0.695, P=0.004), however no correlations were found between the population growth rate and clonal diversity based on either microsatellite genotypes (r=0.320, P=0.245) or a combination of mtCOI haplotype and microsatellite genotypes (r=0.435, P=0.105). Some clones shared mtCOI haplotypes and microsatellite genotypes suggesting sexual reproduction occurred in the hatchery stock of B. koreanus. Statement of relevanceThis study showed the correlation between population growth rate and clonal diversities based on mtCOI haplotypes and microsatellite DNA genotypes in Brachionus koreanus. There was a significant correlation between the population growth rate and haplotype diversity and suggested genetic factor is one of the possible causes affecting population growth rate. Our results will be useful in mass-production and maintenance of Brachionus koreanus at hatcheries.

Development of Gene‐derived SNP Markers and Their Application for the Assessment of Genetic Diversity in Wild and Cultured Populations in Sea Cucumber, Apostichopus japonicus

AbstractThe Apostichopus japonicus is a valuable aquaculture species in China. In this study, 51 single nucleotide polymorphisms (SNPs) were identified from expressed sequence tags of sea cucumber using high‐resolution melting. The average observed heterozygosity (Ho) and expected heterozygosity (He) were 0.2462 and 0.2897, respectively. Thirty‐two of these loci were used for estimating the genetic similarity and variation between the five hatchery stocks from China and two wild stocks from Japan. No significant differences in Ho or He were observed between the wild and hatchery populations. The pairwise Fst (which ranged from 0.0119 to 0.0236) and the genetic identity (which varied from 0.9802 to 0.9915) showed no significant differentiation between the wild and cultured stocks. The analysis of molecular variance indicated the source of variation was at the level of “within the populations.” The information on the genetic variation and differentiation in cultured and wild populations of A. japonicus obtained in this study is useful for setting up suitable guidelines for founding and maintaining of cultured stocks and for future genetic improvement by selective breeding.

Using Radiotelemetry to Compare the Initial Behavior and Mortality of Hatchery‐Reared and Wild Juvenile Florida Bass

AbstractStocking evaluations for pellet‐reared, advanced‐fingerling Largemouth Bass Micropterus salmoides often result in low contribution and survival, but little information exists on their survival and behavior soon after release. This study investigated the behavior and mortality of pellet‐reared, advanced‐fingerling (90–120 mm TL) Florida Bass M. floridanus immediately after they were stocked in Lake Carlton, Florida. A radiotelemetry experiment was conducted to compare initial movement, habitat use, growth, and mortality between stocked hatchery and wild fish. In year 1, we inserted radio transmitters into 50 hatchery fish; in year 2, we tagged 30 hatchery fish and 20 wild fish. All mortality we observed for hatchery fish (from both years) resulted from predation by fish and birds, and most occurred in the first 7 d after tagging. When compared directly with tagged wild fish (n = 20), tagged hatchery fish (n = 30) exhibited greater movement (75 and 124 m/d, respectively), greater proportion of locations offshore (8% and 23%, respectively), slower growth (1.73% and 0.41% of their body weight gained per day, respectively), and higher predation (47% and 0%, respectively). Results of this study suggest that pellet‐reared, hatchery Florida Bass suffer more predation than wild bass of similar size initially following their release into the lake. Causes of predation could include less‐developed antipredator skills and inefficiency in foraging observed through greater movement, as well as the use of offshore habitat and slower growth. We recommend research that investigates acclimating advanced‐fingerling Florida Bass to predators and live prey before release to determine whether initial predation can be reduced after stocking.Received May 29, 2015; accepted December 4, 2015

Genetic evaluation of hatchery stocks of Honmoroko Gnathopogon caerulescens by mitochondrial DNA sequence for stock enhancement

Honmoroko Gnathopogon caerulescens is a critically endangered species and important for commercial fisheries; thus stock enhancement programs are being conducted to restore resources. We evaluated the genetic population structure of field collected samples including spawned eggs around spawning areas in Lake Biwa and the extent of genetic diversity in wild samples and hatchery stocks using sequences of mitochondrial cytochrome b gene. Pairwise Φst analysis and AMOVA clearly showed minimal population structure and haplotype network did not reveal any clear geographic pattern in Lake Biwa. It is probable that strays spawn in non-natal spawning areas, resulting in significant levels of gene flow among spawning areas. Genetic characteristics of hatchery stock F1, F2, and F3 were similar to those of wild samples in terms of haplotype diversity, nucleotide diversity and pairwise Φst values. These results indicate that the relatively high genetic diversity at its initiation was retained due to a lot of broodstock over two successive generations. Accordingly we propose that the current Honmoroko breeding method is appropriate for conserving the genetic diversity of Honmoroko and that the hatchery stock are genetically compatable for release and stock enhancement.

Some results of monitoring for the pink salmon hatchery stocks from the Aniva Bay (Sakhalin Island)

Several population parameters (length and dynamics of spawning run, size-sex composition, variability of morphological and physiological characteristics) are determined and indices of survival are calculated for the pink salmon hatchery stocks from the Aniva Bay of the 2008-2011 generations on the base of the cultured pink salmon differentiation by thermal marks on otoliths. The hatchery pink salmon begin their migration to the bay rivers in late July, together with the wild fish. Size-weight parameters of the fish and their variability are similar for the hatchery and wild stocks in this period, obviously because of low impact of hatcheries on natural reproduction and high portion of wild fish among the spawners used in the hatcheries (> 50 %). Mean portion of the hatchery-reared pink salmon on spawning grounds of the main rivers was 17.9 % in the 2010-2013, the coefficients of their return varied from 1.0 % to 6.4 % that was lower than for the wild fish.

Allozyme Based Genetic Variation between Hatchery and Natural Populations of Sahar (Tor putitora)

Sahar (Tor putitora) formed a substantial natural fishery in the major riverine and lacustrine ecosystem of Nepal. Biological diversity of this species is being threatened by various anthropogenic activities. In view of the conservational value and the aquaculture potential of T. putitora, significant development in artificial propagation of this species has been achieved. The successful hatchery production of T. putitora brought to the forefront problematic questions regarding genetic variation of the hatchery stocks. A study was, therefore, conducted to determine the genetic variability within and between hatchery stocks and their wild counterparts of T. putitora using allozyme markers.Analyses of seven enzyme systems resuled in 11 loci being resolved from lake population and two consecutive generations of hatchery populations of T. putitora. Based on five polymorphic loci, all populations had percentage polymorphic loci 45.45. Significant reduction (P<0.01) in number of alleles per locus was evident in hatchery populations (1.45 ±0.181) compared to lake population (1.72 ±0.90). Loss of rear alleles, EST-2*74, IDH*70 and GDH*33 occurred in both of the hatchery populations which were present in wild counterparts- the lake population. All populations under study conform to the Hardy-Weinberg equilibrium at the 1% level. Although not significant (P>0.05), observed heterozygosity increased in first generation of hatchery population (Ho= 0.181 ±0.233) compared to natural population (Ho=0.179±0.221). The Ho of second generation of hatchery population was lowest (0.119 ±0.143) among the populations studied. Loss of rare alleles from the two generations of hatchery population, while these alleles were present in corresponding natural populations suggested the founders (20-30 individuals) of the hatchery populations probably represented bottlenecks to very small effective population size (Ne).J. Nat. Hist. Mus. Vol. 26, 2012: 212-223

Long-term and seasonal genetic differentiation in wild and enhanced stocks of sea trout (Salmo trutta m. trutta L.) from the Vistula River, in the southern Baltic—Management implications

The Vistula River, rich with sea trout (Salmo trutta m. trutta L.) is the longest river in Poland, flowing into the southern Baltic Sea, with its population sustained mainly by enhancement programmes. The population source was declined and the proportion of Vistula winter and summer sea trout stocks existing in the river was drastically changed over a few decades. This paper is the first detailed genetic study of stocks of the species in the river. Five samples representing wild winter (1971), enhanced winter (2010/11) and summer (2003), and hatchery winter (2003) sea trout stocks were analysed. Twelve microsatellite loci were employed to investigate long-term and seasonal genetic differentiation affected by strong anthropogenic activities and thence to assist fish stock management in the Vistula River. The genetic structure of past and current stocks was observed. The substructure of the sea trout stocks, showing different spawning behaviour, was also exhibited. The drop of private alleles and bottleneck effect were noted, pointing the decrease of Vistula sea trout genetic sources in last 40 years. The pronounced differentiation (pairwise Fst values from 0.024 to 0.057) and high full-siblings share (68%) recorded for the hatchery stock, being the only source for supplementary stocking of winter sea trout stock, imply that this source should be used with caution and action to improve, and subsequently maintain, conditions for natural spawning should be prioritized.

Genotype Reconstruction of Paternity in European Lobsters (Homarus gammarus).

Decapod crustaceans exhibit considerable variation in fertilisation strategies, ranging from pervasive single paternity to the near-ubiquitous presence of multiple paternity, and such knowledge of mating systems and behaviour are required for the informed management of commercially-exploited marine fisheries. We used genetic markers to assess the paternity of individual broods in the European lobster, Homarus gammarus, a species for which paternity structure is unknown. Using 13 multiplexed microsatellite loci, three of which are newly described in this study, we genotyped 10 eggs from each of 34 females collected from an Atlantic peninsula in the south-western United Kingdom. Single reconstructed paternal genotypes explained all observed progeny genotypes in each of the 34 egg clutches, and each clutch was fertilised by a different male. Simulations indicated that the probability of detecting multiple paternity was in excess of 95% if secondary sires account for at least a quarter of the brood, and in excess of 99% where additional sire success was approximately equal. Our results show that multiple paternal fertilisations are either absent, unusual, or highly skewed in favour of a single male among H. gammarus in this area. Potential mechanisms upholding single paternal fertilisation are discussed, along with the prospective utility of parentage assignments in evaluations of hatchery stocking and other fishery conservation approaches in light of this finding.

An evaluation of the contribution of hatchery stocking on population density and biomass: a lesson from masu salmon juveniles within a Japanese river system

AbstractStocking is an important management tool for enhancing fisheries resources, but its actual contribution to fisheries resources is controversial, taking into consideration both the positive and negative effects. This study compared density and biomass of hatchery (otolith thermal marked) and wild masu salmon parr between stocked and unstocked rivers to evaluate the contribution of stocking with hatchery‐reared fish. Density and biomass of all fish did not differ between stocked and unstocked rivers. Moreover, density and biomass of wild fish in the stocked rivers were lower than those of the unstocked rivers. Density and biomass of hatchery fish in a non‐natural reproducing river were similar with those of all fish in natural reproducing rivers. These results indicate that hatchery stocking does not have positive effects on population density or biomass but replaces wild fish with hatchery fish and that non‐natural reproducing areas are more suitable as stocking sites.

First-generation genetic drift and inbreeding risk in hatchery stocks of the wreckfish Polyprion americanus

The wreckfish Polyprion americanus is a component of directed and admixed species fisheries throughout its world range and has recently been identified for its aquaculture potential. Several wreckfish broodstocks were founded in Galician hatcheries in the last decade and are now approaching maturity. The combination of genetic markers with classic domestication strategies is a pertinent approach to preserve genetic variation and to slow down consanguineous-derived adverse effects. Genetic data from microsatellites used to characterize four Galician wreckfish stocks provide evidence of both, a significant interstock differentiation (7.60%) and a pronounced loss of allele diversity (26%) in 80% of the stocks. Such artificial sub-structuring linked to the erosion of gene diversity is most likely caused by sampling drift that stepped up from the North Atlantic population. Computer simulation of relatedness helps to appraise alternate breeding protocols to avoid uncontrolled inbreeding within stocks. We show that under a fixed number of breeders and a sex balanced contribution, two protocols consisting on random mating among broodstocks (ΔRxy=2.21%) or enhanced with a wild sample (ΔRxy=0.97%), are far more advantageous strategies to slow inbreeding in F1 and F2 than breeding protocols within stock (ΔRxy=6.6%). Statement of relevanceIn silico scenarios upon real data help slowing inbreeding