Low mtDNA diversity in a highly differentiated population of spinner dolphins (Stenella longirostris) from the Fernando de Noronha Archipelago, Brazil

Made available in DSpace on 2020-12-12T02:01:37Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-01-01 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Spinner dolphins (Stenella longirostris, Gray 1828) are widely distributed in tropical waters around the world. Although they occur in large, pelagic groups in the Eastern Tropical Pacific, elsewhere in the Pacific they are found in small and genetically isolated populations associated with islands. This species is considered to be “Least Concern” (LC) by the World Conservation Union (IUCN). To assess genetic diversity and population structure of an island-associated population in the South Atlantic Ocean we surveyed 162 spinner dolphins throughout the Fernando de Noronha Archipelago of the northeast coast of Brazil using ten microsatellite loci and sequencing a 413-bp section of the mitochondrial DNA (mtDNA) control region. Eleven mtDNA haplotypes were identified and haplotype diversity (h) and nucleotide diversity (π) were 0.3747 and 0.0060, respectively. Median-Joining Network revealed the presence of two very divergent haplotypes and F-statistics indicated some heterogeneity between two sampling years. All microsatellite loci were polymorphic (Ho: 0.767; He: 0,764) but, revealed no detectable substructure. We also compared the mtDNA haplotypes from Noronha to 159 haplotypes representing 893 individuals from 14 locations worldwide. We found that the two common haplotypes from the Fernando de Noronha Archipelago were absent in all other populations. These comparisons showed that Noronha spinner dolphins are likely more differentiated than other island populations, suggesting that they form societies with strong site fidelity mediated by females. Departamento de Ciências Biológicas Universidade Federal do Espírito Santo (UFES) Instituto Chico Mendes de Conservação da Biodiversidade (ICMBio) Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA) Embrapa Recursos Genéticos e Biotecnologia Instituto de Biociências Departamento de Genética Universidade Estadual Paulista Júlio de Mesquita Filho (UNESP) Instituto de Biociências Campus do Litoral Paulista Universidade Estadual Paulista Júlio de Mesquita Filho (UNESP) Marine Mammal Institute Hatfield Marine Science Center Oregon State University Departamento de Ciências Agrárias e Biológicas Universidade Federal do Espírito Santo (UFES) Instituto de Biociências Departamento de Genética Universidade Estadual Paulista Júlio de Mesquita Filho (UNESP) Instituto de Biociências Campus do Litoral Paulista Universidade Estadual Paulista Júlio de Mesquita Filho (UNESP)