RESUMEN
We developed a set of hypervariable microsatellite markers for the Pacific red snapper (Lutjanus peru), an economically important marine fish for small-scale fisheries in the west coast of Mexico. We performed shotgun genome sequencing with the 454 XL titanium chemistry and used bioinformatic tools to search for perfect microsatellite loci. We selected 66 primer pairs that were synthesized and genotyped in an ABI PRISM 3730XL DNA sequencer in 32 individuals from the Gulf of California. We estimated levels of genetic diversity, deviations from linkage and Hardy-Weinberg equilibrium, estimated the frequency of null alleles and the probability of individual identity for the new markers. We reanalyzed 16 loci in 16 individuals to estimate genotyping error rates. Eighteen loci failed to amplify, 16 loci were discarded due to unspecific amplifications and 32 loci (14 tetranucleotide and 18 dinucleotide) were successfully scored. The average number of alleles per locus was 21 (±6.87, SD) and ranged from 8 to 34. The average observed and expected heterozygosities were 0.787 (±0.144 SD, range 0.250-0.935) and 0.909 (±0.122 SD, range 0.381-0.965), respectively. No significant linkage was detected. Eight loci showed deviations from Hardy-Weinberg equilibrium, and from these, four loci showed moderate null allele frequencies (0.104-0.220). The probability of individual identity for the new loci was 1.46-62. Genotyping error rates averaged 9.58%. The new markers will be useful to investigate patterns of larval dispersal, metapopulation dynamics, fine-scale genetic structure and diversity aimed to inform the implementation of spatially explicit fisheries management strategies in the Gulf of California.
Asunto(s)
Perciformes/genética , Análisis de Secuencia de ADN/métodos , Alelos , Animales , Cartilla de ADN/genética , Explotaciones Pesqueras , Peces/genética , Frecuencia de los Genes/genética , Ligamiento Genético/genética , Sitios Genéticos/genética , Variación Genética/genética , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Desequilibrio de Ligamiento/genética , México , Repeticiones de Microsatélite/genéticaRESUMEN
We examined recruitment and ontogenetic habitat shifts of the yellow snapper Lutjanus argentiventris in the Gulf of California, by conducting surveys and collections in multiple mangrove sites and major marine coastal habitats from 1998 to 2007. Over 1,167 juvenile individuals were collected and 516 otoliths were aged to describe the temporal pattern of the settlement. L. argentiventris recruits in mangroves, where juveniles remain until they are approximately 100 mm in length or 300-days-old. Back-calculated settlement dates and underwater surveys indicated a major recruitment peak during September and October, around 8 days before and after the full moon. The majority of mangrove sites in the Gulf of California had a similar L. argentiventris average size at the beginning of the settlement season for the cohort of 2003; although there were significant differences in individual sizes at the end of the nursery stage. When sub-adults leave mangroves, they live in shallow rocky reefs and later become abundant in deeper rocky reefs. The density of migratory individuals (10-20 cm SL) decreased exponentially as the distance between a reef and a nearby mangrove site increased. This finding has important implications for local fishery regulations and coastal management plans.