Population connectivity plays significant roles on both evolutionary and ecological time-scales; however, quantifying the magnitude and pattern of ex- change between populations of marine organisms is hindered by the difficulty of tracking the trajectory and fate of propagules. We explored biophysical correlates of population substructure to determine how well pelagic larval duration (PLD) correlates with population genetic estimates of connectivity in a sample of 300 published studies drawn pseudo-randomly from about 1600 hits on electronic searches. In direct contrast to the general expectation of a strong correlation, we find that average PLD is poorly correlated (r 2 < 0.1) with genetic structure (FST). Furthermore, even this weak correlation is anchored by non-pelagic dispersal, because removal of the zero PLD class (direct developers) from the analy- sis resulted in a non-significant relationship between FST and PLD. For species in which minimum, maximum, and mean PLDs were available, it is noteworthy that both minimum and maximum PLDs are better corre- lated with FST than the mean larval duration, which has been used in all such previous studies. A 3-way AN- COVA reveals that genetic marker class (allozymes, microsatellites, and mitochondrial DNA sequences), as opposed to habitat or swimming ability, explain most of the variation in FST (F = 7.113, df = 2, p = 0.001), with higher values of FST obtained from mtDNA than with either microsatellites or allozymes (which were not sig- nificantly different). Our meta-analysis refutes recent reviews and conventional wisdom that PLD is a good predictor of the magnitude of gene flow and geo- graphic scale of population structure in marine systems.

/pdf/population-genetics-larval-dispersal-and-connectivity-in-148msamk1s.pdf

Population genetics, larval dispersal, and connectivity in marine systems

Is hatchery stocking a help or harm? Evidence, limitations and future directions in ecological and genetic surveys

Molecular genetic data have found widespread application in the identification of population and conservation units for aquatic species. However, integration of genetic information into actual management has been slow, and explicit and quantitative inclusion of genetic data into fisheries models is rare. In part, this reflects the inherent difficulty in using genetic markers to draw inferences about demographic independence, which is generally the information of the greatest short-term interest to fishery managers. However, practical management constraints, institutional structures and communication issues have also contributed to the lack of integration. This paper identifies some of the organizational, conceptual and technical barriers that have hampered full use of genetics data in stock assessment and hence fishery management and outlines how such use could be enhanced.

/pdf/integrating-genetic-data-into-management-of-marine-resources-51hjz8nn85.pdf

Integrating genetic data into management of marine resources: how can we do it better?

Preface. Editorial Note on Terminology. Acknowledgments. I. Artemia Morphology and Structure. II. Reproductive Biology of Artemia. III. Physiological and Biochemical Aspects of Artemia Ecology. IV. Zoogeography. V. Evolution and Speciation. VI. Applications of Artemia. Index.

Artemia: Basic and Applied Biology

http://faculty.jsd.claremont.edu/emorhardt/159/pdfs/2006/Teletchea2.pdf

Food and forensic molecular identification: update and challenges.

Loss of genetic variation at microsatellite loci in hatchery produced abalone in Australia (Haliotis rubra) and South Africa (Haliotis midae)

Genetic diversity in Haliotis midae, a highly valued and heavily exploited marine gastropod, was assessed using 3 marker types across samples from the species' range in South Africa. Variation was compared at 7 allozyme loci, 2 regions of mitochondrial DNA and 3 microsatellite loci. We conclude that populations of H. midae on either side of Cape Agulhas represent 2 independent reproductive stocks. The area of transition between the stocks coincides with oceanographic features of the region. Evidence from all 3 types of genetic marker indicates an isolated introduction event to the east of Cape Agulhas, and subsequent range expansion in an easterly direction. The disparity between allozyme data and the other 2 forms is seen as further evidence for the presence of balanc- ing selection at allozyme loci.

/pdf/population-genetic-structure-of-the-perlemoen-haliotis-midae-wkza91939k.pdf

Population genetic structure of the perlemoen Haliotis midae in South Africa: evidence of range expansion and founder events

Athough the incidence of abalone poaching is increasing in South Africa, several alleged poachers have been acquitted in cases where the state has been unable to prove that the confiscated meat is of the local abalone. Halimis midae. This species is illegally exported to the Far East by poaching syndicates, a practice that is undermining the legitimate industry. To solve this, a polymerase chain reaction (PCR) technique that targets a portion of the lysin gene of several abalone species and unequivocally distinguishes between H. midae and H. spadicea (a sympatric congeneric) has been developed. The PCR primers specifically amplify approximately 1 ,300 bp of genomic DNA from dried, cooked, and fresh abalone tissue. A smaller fragment of 1 46 bp is used for canned abalone. Restriction fragment length polymorphism (RFLP) exploit interspecific polymorphisms that discriminate between these two species. The method can also be used to identify H. rubra and can easily be adapted to other abalone species under the same threat of overexploitation.

A PCR technique for forensic, species-level identification of abalone tissue

Biochemical and molecular species identification techniques have a broad range of applications in the management and conservation of marine organisms. While species boundaries are not always clearly defined, phylogeneticists utilise autapomorphic characters to distinguish phylogenetic species. Genetic markers discriminate between marine taxa when traditional morphological distinctions are unclear. The applications of these techniques can be divided into four general categories. Firstly, compliance enforcement, which often depends on genetic identification techniques to enable officials to identify the species to which regulations pertain. Secondly, quality control applications, to allow for the testing of marine products to guard against fraudulent substitution with less valuable species, which is particularly pertinent since processing often obliterates identifiable features. Thirdly, a variety of applications to ecological and life-history studies and conservation management are reported. Here, the genetic identification techniques of species from cryptic life-cycle stages or of morphologically indistinct species are an indispensable tool for marine scientists, conservators and managers. Lastly, the application of genetic techniques for sourcing population origin is briefly discussed. The biochemical and molecular techniques applied to species identification all exploit phenotypic or genotypic polymorphisms that are sampled using either tertiary level protein based methods or primary level DNA based methods. In this review, examples of the applications along with the total protein, allozyme, serological, PCR and other DNA based methodologies are briefly described and some generalities with regard to their use are presented.

Molecular genetics and the management and conservation of marine organisms

Species identification based on biochemical and molecular techniques has a broad range of applications. These include compliance enforcement, the management and conservation of marine organisms, and commercial quality control. Abalone poaching worldwide and illegal trade in abalone products have increased mainly because of the attractive prices obtained and caused a sharp decline in stocks. Alleged poachers have been acquitted because of lack of evidence to correctly identify species. Therefore, a robust method is required that would identify tissue of abalone origin to species level. The aim of this study was to develop immunologic techniques, using monoclonal and polyclonal antibodies, to identify 10 different abalone species and subspecies from South Africa, the United States, Australia, and Japan. The combination of 3 developed monoclonal antibodies to South African abalone (Haliotis midae) enabled differentiation between most of the 10 species including the subspecies H. diversicolor supertexta and H. diversicolor diversicolor. In a novel approach, using antibodies of patients with allergy to abalone, the differentiation of additional subspecies, H. discus discus and H. discus hannai, was possible. A field-based immunoassay was developed to identify confiscated tissue of abalone origin.

Neville A. Sweijd

Papers

Loss of genetic variation at microsatellite loci in hatchery produced abalone in Australia (Haliotis rubra) and South Africa (Haliotis midae)

Population genetic structure of the perlemoen Haliotis midae in South Africa: evidence of range expansion and founder events

A PCR technique for forensic, species-level identification of abalone tissue

Molecular genetics and the management and conservation of marine organisms

Development of a monoclonal antibody detection assay for species-specific identification of abalone.