Resource Status and Effect of Long-Term Stock Enhancement of Large Yellow Croaker in China

The large yellow croaker, Larimichthys crocea, was once the most abundant and economically important marine fish in China. Thus far, it has also been the most successful mariculture fish species in China. However, its wild stock severely declined in the 1970s because of overexploitation, and therefore hatchery release has been carried out for stock enhancement since 2000. As a migratory fish, large yellow croaker was divided into three geographical stocks according to ambiguous morphological and biological characteristics in early documents. To investigate the identity of wild large yellow croaker populations and assess the influence of hatchery supplementation on wild populations, a total of 2,785 cultured individuals and 591 wild individuals were collected from 91 hatcheries and six wild populations along the coast of mainland China and analyzed using two mitochondrial genes [cytochrome oxidase I (COI) and cytochrome b (Cyt b)] and one nuclear gene (RyR3). The higher haplotype diversity and moderate nucleotide diversity of wild large yellow croaker indicated that overexploitation, which caused a sharp decrease in biomass, did not lead to a loss of genetic diversity. According to phylogenetic construction and network analysis, the absence of a significant population structure pattern revealed a single panmictic population of wild large yellow croaker with exception of a population collected from the Sansha Bay, which showed high genetic relatedness to the cultured population, suggesting significant genetic effects resulting from stock enhancement. Overall, our study suggests no genetic differentiation in the entire wild population of large yellow croaker, which means that we have great flexibility in mixing and matching farmed and wild populations. However, since the result showed that domestication, the relaxation of purifying selection, increased genetic loads, and maladapted farmed fish will be at a selective disadvantage when cultured juveniles are released in the wild, the effectiveness of stock enhancement and the negative impact of hatchery-wild fish hybridization on the wild population must be carefully evaluated in future.

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A horizontally transferred nuclear gene is associated with microhabitat variation in a natural plant population

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2015.2453 ◽

2015 ◽

Vol 282 (1821) ◽

pp. 20152453 ◽

Cited By ~ 8

Author(s):

Honor C. Prentice ◽

Yuan Li ◽

Mikael Lönn ◽

Anders Tunlid ◽

Lena Ghatnekar

Keyword(s):

Horizontal Gene Transfer ◽

Wild Population ◽

Genetic Material ◽

Nuclear Gene ◽

Adaptive Significance ◽

Fine Scale ◽

Spatial Effects ◽

Wild Populations ◽

Natural Plant ◽

Habitat Variation

Horizontal gene transfer involves the non-sexual interspecific transmission of genetic material. Even if they are initially functional, horizontally transferred genes are expected to deteriorate into non-expressed pseudogenes, unless they become adaptively relevant in the recipient organism. However, little is known about the distributions of natural transgenes within wild species or the adaptive significance of natural transgenes within wild populations. Here, we examine the distribution of a natural plant-to-plant nuclear transgene in relation to environmental variation within a wild population. Festuca ovina is polymorphic for an extra (second) expressed copy of the nuclear gene ( PgiC ) encoding cytosolic phosphoglucose isomerase, with the extra PgiC locus having been acquired horizontally from the distantly related grass genus Poa. We investigated variation at PgiC in samples of F. ovina from a fine-scale, repeating patchwork of grassland microhabitats, replicated within spatially separated sites. Even after accounting for spatial effects, the distributions of F. ovina individuals carrying the additional PgiC locus, and one of the enzyme products encoded by the locus, are significantly associated with fine-scale habitat variation. Our results suggest that the PgiC transgene contributes, together with the unlinked ‘native’ PgiC locus, to local adaptation to a fine-scale mosaic of edaphic and biotic grassland microhabitats.

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Low genetic diversity in captive populations of the critically endangered Blue-crowned Laughingthrush (Garrulax courtoisi) revealed by a panel of novel microsatellites

PeerJ ◽

10.7717/peerj.6643 ◽

2019 ◽

Vol 7 ◽

pp. e6643

Author(s):

Guoling Chen ◽

Chenqing Zheng ◽

Nelson Wan ◽

Daoqiang Liu ◽

Vivian Wing Kan Fu ◽

...

Keyword(s):

Genetic Diversity ◽

Haplotype Analysis ◽

Genetic Relatedness ◽

Wild Population ◽

Critically Endangered ◽

Assignment Test ◽

Microsatellite Data ◽

Wild Populations ◽

Captive Populations ◽

Mitochondrial Data

Background Captive populations permit research and conservation of endangered species in which these efforts are hardly implemented in wild populations. Thus, analysing genetic diversity and structure of captive populations offers unique opportunities. One example is the critically endangered Blue-crowned Laughingthrush, Garrulax courtoisi, which has only two known wild populations in Wuyuan, Jiangxi and Simao, Yunnan, China. We carried out the first conservation genetic study, in order to provide useful implications that allow for successful ex situ conservation and management of the Blue-crowned Laughingthrush. Methods Using the novel microsatellite markers developed by whole-genome sequencing, we genotyped two captive populations, from the Ocean Park Hong Kong, which are of unknown origin, and the Nanchang Zoo, which were introduced from the Wuyuan wild population since the year 2010–2011, respectively. The genetic diversity of captive Blue-crowned Laughingthrush populations was estimated based on genetic polymorphisms revealed by a new microsatellite data set and mitochondrial sequences. Then, we characterised the population structure using STRUCTURE, principal coordinates analysis, population assignment test using the microsatellite data, and haplotype analysis of mitochondrial data. Additionally, we quantified genetic relatedness based on the microsatellite data with ML-Relate. Results Our results showed equally low levels of genetic diversity of the two captive Blue-crowned Laughingthrush populations. The population structure analysis, population assignment test using the microsatellite data, and haplotype analysis of the mitochondrial data showed weak population structuring between these two populations. The average pairwise relatedness coefficient was not significant, and their genetic relatedness was quantified. Discussion This study offers a genetic tool and consequently reveals a low level of genetic diversity within populations of a critically endangered bird species. Furthermore, our results indicate that we cannot exclude the probability that the origin of the Hong Kong captive population was the wild population from Wuyuan. These results provide valuable knowledge that can help improve conservation management and planning for both captive and wild Blue-crowned Laughingthrush populations.

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STOCK ENHANCEMENT IN INDONESIAN LAKE AND RESERVOIRS FISHERIES

Indonesian Fisheries Research Journal ◽

10.15578/ifrj.18.2.2012.91-100 ◽

2012 ◽

Vol 18 (2) ◽

pp. 91

Author(s):

Endi Setiadi Kartamihardja

Keyword(s):

Negative Impact ◽

Basic Research ◽

Stock Enhancement ◽

Fish Stock ◽

Aquatic Weed ◽

Fish Production ◽

Program Success ◽

Water Surface Area ◽

Fish Catch ◽

Lakes And Reservoirs

A total water surface area of lakes and reservoirs of Indonesia is 2.3 million hectares. To increase fish production in Indonesian lakes and reservoirs, fish stock enhancement were practiced. A review on fish stock enhancement in Indonesian lakes and reservoirs was conducted. Some species used in stock enhancement were reviewed, and the causes of program success or failure were analyzed in an attempt to determine the best approach for future stocking. Since 2000 the success of the project on fish stock enhancement were supported by basic research on diet, ecological niche, life cycle and behavior of the species stocked. Recent successes in fish stock enhancement are mainly determined by species which can be reproduced naturally in the water bodies. Nile tilapia (Oreochromis niloticus), Siamese cat fish (Pangasionodon hypophthalmus) and small carp (bilih, Mystacoleucus padangensis), an endemic species are the species have best performances in the increasing fish production significantly. Milk fish (Chanos chanos) stock enhancement can be used to mitigate the negative impact of cage culture in the reservoir. While grass carp (Ctenopharyngodon idellus) has been successful in controlling aquatic weed, Eichhornia crassipes in some lakes. Management of fish stock enhancement including providing quality and quantity of seeds, regulating of fish catch, developin g of market system, institution and fisheries co-management have supported a steady yearly increase in yield. The governments should take the initiative in protection of genetic diversity, especially in stock enhancement of lakes inhabited by endemic and or threatened species, such as lakes in Sulawesi and Papua Island.

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Genealogical relationship inference to identify areas of intensive poaching of the Orange-fronted Parakeet (Eupsittula canicularis)

BMC Zoology ◽

10.1186/s40850-021-00080-y ◽

2021 ◽

Vol 6 (1) ◽

Author(s):

Gabriela Padilla-Jacobo ◽

Tiberio C. Monterrubio-Rico ◽

Horacio Cano-Camacho ◽

María Guadalupe Zavala-Páramo

Keyword(s):

Genetic Diversity ◽

Dna Sequences ◽

Haplotype Diversity ◽

Coastal Region ◽

Central American ◽

Illegal Trade ◽

Wild Populations ◽

High Genetic Diversity ◽

Genealogical Relationship ◽

Genetic Pool

Abstract Background The Orange-fronted Parakeet (Eupsittula canicularis) is the Mexican psittacine that is most captured for the illegal pet trade. However, as for most wildlife exploited by illegal trade, the genetic diversity that is extracted from species and areas of intensive poaching is unknown. In this study, we analyzed the genetic diversity of 80 E. canicularis parakeets confiscated from the illegal trade and estimated the level of extraction of genetic diversity by poaching using the mitochondrial DNA sequences of cytochrome b (Cytb). In addition, we analyzed the genealogical and haplotypic relationships of the poached parakeets and sampled wild populations in Mexico, as a strategy for identifying the places of origin of poached parakeets. Results Poached parakeets showed high haplotype diversity (Hd = 0.842) and low nucleotide diversity (Pi = 0.00182). Among 22 haplotypes identified, 18 were found exclusively in 37 individuals, while four were detected in the remaining 43 individuals and shared with the wild populations. A rarefaction and extrapolation curve revealed that 240 poached individuals can include up to 47 haplotypes and suggested that the actual haplotype richness of poached parakeets is higher than our analyses indicate. The geographic locations of the four haplotypes shared between poached and wild parakeets ranged from Michoacan to Sinaloa, Mexico. However, the rare haplotypes detected in poached parakeets were derived from a recent genetic expansion of the species that has occurred between the northwest of Michoacan and the coastal region of Colima, Jalisco and southern Nayarit, Mexico. Conclusions Poached parakeets showed high genetic diversity, suggesting high extraction of the genetic pool of the species in central Mexico. Rarefaction and extrapolation analyses suggest that the actual haplotype richness in poached parakeets is higher than reflected by our analyses. The poached parakeets belong mainly to a very diverse genetic group of the species, and their most likely origin is between northern Michoacan and southern Nayarit, Mexico. We found no evidence that poachers included individuals from Central American international trafficking with individuals from Mexico in the sample.

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Disinfection effect of povidone-iodine in aquaculture water of swamp eel (Monopterus albus)

PeerJ ◽

10.7717/peerj.5523 ◽

2018 ◽

Vol 6 ◽

pp. e5523

Author(s):

Xuan Chen ◽

Chongde Lai ◽

Yulan Wang ◽

Lili Wei ◽

Qiwang Zhong

Keyword(s):

Povidone Iodine ◽

Negative Impact ◽

Iodine Content ◽

Economic Loss ◽

Luria Bertani ◽

Toxicity Tests ◽

Farmed Fish ◽

Monopterus Albus ◽

Aquaculture Water ◽

Swamp Eel

The swamp eel (Monopterus albus) is an important commercial farmed fish species in China. However, it is susceptible toAeromonas hydrophilainfections, resulting in high mortality and considerable economic loss. Povidone-iodine (PVP-I) is a widely used chemical disinfectant in aquaculture, which can decrease the occurrence of diseases and improve the survival. However, environmental organic matter could affect the bactericidal effectiveness of PVP-I, and the efficacy of PVP-I in aquaculture water is still unknown. In this paper, disinfection assays were conducted to evaluate the effectiveness of PVP-I against theA. hydrophilain different types of water. We found that the effective germicidal concentration of PVP-I in outdoor aquaculture water was 25 ppm for 12 h. In indoor aquaculture water with 105CFU/mL bacteria, 10 ppm and 20 ppm of PVP-I could kill 99% and 100% of the bacteria, respectively. The minimal germicidal concentration of PVP-I in Luria-Bertani broth was 4,000 ppm. Available iodine content assay in LB solutions confirmed that the organic substance had negative impact on the effectiveness of PVP-I, which was consistent with the different efficacy of PVP-I in different water samples. Acute toxicity tests showed that the 24 h-LC50of PVP-I to swamp eel was 173.82 ppm, which was much higher than the germicidal concentrations in outdoor and indoor aquaculture water, indicating its safety and effectivity to control theA. hydrophila. The results indicated PVP-I can be helpful for preventing the transmission ofA. hydrophilain swamp eel aquaculture.

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Field selectivity of a spinosad-poisoned bait toward target tephritids and non-target insects

Bollettino della Società Entomologica Italiana ◽

10.4081/bollettinosei.2014.11 ◽

2014 ◽

pp. 11-15 ◽

Cited By ~ 1

Author(s):

Marco Infusino ◽

Nino Iannotta ◽

Stefano Scalercio

Keyword(s):

Pest Control ◽

Ceratitis Capitata ◽

Negative Impact ◽

Control Strategies ◽

Field Trials ◽

Pest Species ◽

Wild Populations ◽

Target Species ◽

Key Points ◽

Insect Monitoring

One of the key-points in sustainable agriculture is to minimize the amount of pesticides inputs in agro-ecosystems increasing selectivity of active agents on target pests mainly. According to this perspective, control strategies utilising baits receive a growing interest. a spinosad-poisoned sugar-based bait, the so called GF-120 bait, utilised against diptera Tephritidae, recently appeared on the market. The toxicity of spinosad for non-target insects is demonstrated by several authors. However, the amount of pesticide applied is strongly reduced by using it with an attractive food-bait, even if field evidences on the selective attraction of this bait are missing. The aim of this paper is to evaluate the selectivity of GF-120 bait toward target and non-target insects under field conditions, focussing our attention on pollinators. Field trials were performed in a 20 years old olive orchard, where 12 baited and 12 unbaited traps were positioned for insect monitoring. The abundance of the most common orders of insects and target pest species Bactrocera oleae and Ceratitis capitata has been assessed. The main finding of this research is that many pollinators are not attracted by the bait, while target and non-target diptera are significantly attracted by the bait with the exception of Muscidae. The attraction toward a part of non-target diptera should be better explored in order to avoid negative impact on beneficial and non-target species. The need of pest control strategies safer for the environment and the wild populations of non-target organisms seems to be satisfied by the use of this bait.

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Stable producer–scrounger dynamics in wild birds: sociability and learning speed covary with scrounging behaviour

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2016.2872 ◽

2017 ◽

Vol 284 (1852) ◽

pp. 20162872 ◽

Cited By ~ 10

Author(s):

L. M. Aplin ◽

J. Morand-Ferron

Keyword(s):

Multiple Scales ◽

Wild Population ◽

Bimodal Distribution ◽

Wild Populations ◽

Extensive Game ◽

Learning Speed ◽

The Social ◽

Game Theoretic ◽

Foraging Task ◽

Broad Scale

There has been extensive game-theoretic modelling of conditions leading to equilibria of producer–scrounger dichotomies in groups. However there is a surprising paucity of experimental evidence in wild populations. Here, we examine producer–scrounger games in five subpopulations of birds feeding at a socially learnt foraging task. Over four weeks, a bimodal distribution of producers and scroungers emerged in all areas, with pronounced and consistent individual tactic specialization persisting over 3 years. Tactics were unrelated to exploratory personality, but correlated with latency to contact and learn the foraging task, with the late arrivers and slower learners more likely to adopt the scrounging role. Additionally, the social environment was also important: at the broad scale, larger subpopulations with a higher social density contained proportionally more scroungers, while within subpopulations scroungers tended to be central in the social network and be observed in larger foraging flocks. This study thus provides a rare example of a stable, dimorphic distribution of producer–scrounger tactics in a wild population. It further gives support across multiple scales for a major prediction of social foraging theory; that the frequency of scroungers increases with group size.

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Agronomic value and morphophysiological diversity of non-Ladino Italian white clover wild populations compared with variety germplasm

Crop and Pasture Science ◽

10.1071/cp11350 ◽

2012 ◽

Vol 63 (4) ◽

pp. 377 ◽

Cited By ~ 4

Author(s):

P. Annicchiarico

Keyword(s):

Seed Yield ◽

White Clover ◽

Competitive Ability ◽

Wild Population ◽

Total Yield ◽

Reproductive Traits ◽

Northern Italy ◽

Forage Yield ◽

High Yield ◽

Wild Populations

Non-Ladino Italian white clover wild populations are widespread in hill and mountain areas of the Alps and northern Apennines. The agronomic value of these populations is unknown. This study was based on results of four experiments and had the following objectives: (i) comparing 11 small-leaved or medium-leaved wild populations from these areas with eight medium-leaved or large-leaved varieties of different origin and one wild population from Sardinia, for forage yield in a mown association with cocksfoot, forage yield under sheep grazing, seed yield, forage quality, and 14 vegetative or reproductive traits; (ii) investigating the relationships among traits; (iii) assessing the association of individual trait expression with the environments of origin of the wild populations. Clover competitive ability was greater in large-leaved material, tended to imply higher total yield of the association, and was unrelated to clover yield under grazing. Most wild populations from northern Italy were acyanogenic, several exhibited high yield under grazing and high seed yield, and one medium-leaved wild population outperformed any medium-leaved variety for forage and seed yield traits. Higher altitude of collecting site of these populations was related to lower forage yield and smaller size of some traits. Pasture collecting habitat implied greater adaptation to grazing than woodland, greater competitive ability than wasteland, and several morphophysiological differences relative to populations collected from wasteland or meadow. The Sardinian wild population displayed low seed yield and high cyanogenic potential, whereas the Ladino variety Giga was top-performing for forage yield in association and seed yield. Several vegetative and reproductive traits showed covariation. The generated results can drive the exploitation of non-Ladino genetic resources from northern Italy.

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AN IMPLICIT COVER PROBLEM IN WILD POPULATION STUDY

Discrete Mathematics Algorithms and Applications ◽

10.1142/s1793830910000449 ◽

2010 ◽

Vol 02 (01) ◽

pp. 21-31 ◽

Cited By ~ 1

Author(s):

MARY V. ASHLEY ◽

TANYA Y. BERGER-WOLF ◽

WANPRACHA CHAOVALITWONGSE ◽

BHASKAR DASGUPTA ◽

ASHFAQ KHOKHAR ◽

...

Keyword(s):

Optimization Problem ◽

Wild Population ◽

Combinatorial Optimization Problem ◽

Set Cover ◽

Not Given ◽

Wild Populations ◽

Feedback Arc Set ◽

Hitting Set ◽

Cover Problem ◽

Hitting Set Problem

In an implicit combinatorial optimization problem, the constraints are not enumerated explicitly but rather stated implicitly through equations, other constraints or auxiliary algorithms. An important subclass of such problems is the implicit set cover (or, equivalently, hitting set) problem in which the sets are not given explicitly but rather defined implicitly. For example, the well-known minimum feedback arc set problem is such a problem. In this paper, we consider such a cover problem that arises in the study of wild populations in biology in which the sets are defined implicitly via the Mendelian constraints and prove approximability results for this problem.

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Genetic impact of gadoid culture on wild fish populations: predictions, lessons from salmonids, and possibilities for minimizing adverse effects

ICES Journal of Marine Science ◽

10.1016/j.icesjms.2005.11.003 ◽

2006 ◽

Vol 63 (2) ◽

pp. 198-208 ◽

Cited By ~ 57

Author(s):

Dorte Bekkevold ◽

Michael M. Hansen ◽

Einar E. Nielsen

Keyword(s):

Life History Traits ◽

Wild Population ◽

General Trend ◽

Fish Populations ◽

Gene Pools ◽

Wild Populations ◽

Genetic Studies ◽

Hatchery Fish ◽

Genetic Impact ◽

Up Scaling

Abstract Little is known about the effects of ranched gadoids escaping into wild populations, and plans for substantial up-scaling of gadoid mariculture raise concerns about detrimental effects on local gene pools. Genetic studies from salmonid populations subjected to intentional or unintentional releases of hatchery-produced fish suggest that wild gene pools are affected by introgression, but that the genetic impact can be minor relative to expectations from the often substantial numbers of released hatchery fish. However, even if resilience to introgression is a general trend, wild population fitness is still predicted to be jeopardized by releases. In this paper, we review theoretical genetic effects of escapes of cultivated individuals and the empirical evidence for introgression effects, which are based mainly on salmonid studies. Based on knowledge of gadoid population structure and life history traits, we make predictions for effects of gadoid mariculture on wild populations and discuss approaches for monitoring and minimizing introgression effects.

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