Genetic differentiation and limited gene flow among fragmented populations of New Zealand endemic Hector’s and Maui’s dolphins

  title={Genetic differentiation and limited gene flow among fragmented populations of New Zealand endemic Hector’s and Maui’s dolphins},
  author={Rebecca M. Hamner and Franz B. Pichler and Dorothea Heimeier and Rochelle Constantine and C. Scott Baker},
  journal={Conservation Genetics},
Gene flow among small fragmented populations is critical for maintaining genetic diversity, and therefore the evolutionary potential of a species. [] Key Method Our work examined genetic differentiation and migration between the subspecies and among regional and local Hector’s dolphin populations using mitochondrial (mt) DNA and microsatellite genotypes from 438 samples. Results confirmed earlier reports of a single unique mtDNA control region haplotype fixed in the Maui’s dolphin, and provided new evidence…
The Influence of Selection on MHC DQA and DQB Haplotypes in the Endemic New Zealand Hector’s and Māui Dolphins
A complex interplay of balancing selection, directional selection, local fidelity, and genetic drift is suggested in the endangered Hector's dolphin and critically endangered Māui dolphin populations.
Long-range movement by Hector's dolphins provides potential genetic enhancement for critically endangered Maui's dolphin
The genetic monitoring of Maui's dolphins revealed the first contemporary dispersal of their sister subspecies, Hector's dolphin, from New Zealand's South Island into the Maui’s dolphin distribution along ~300 km of the North Island's northwest coast, demonstrating long-distance dispersal by Hector's dolphins and the possibility of an unsampled Hector's Dolphin population along the southwest coast of theNorth Island.
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Microsatellite Markers Reveal Strong Genetic Structure in the Endemic Chilean Dolphin
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Geographic Isolation of Hector’s Dolphin Populations Described by Mitochondrial DNA Sequences
The low rate of female dispersal, as indicated by this mitochondrial DNA structure, could increase the vulnerability of local populations to extinction due to fisheries‐related mortality.
Hierarchical structure of mitochondrial DNA gene flow among humpback whales Megaptera novaeangliae, world‐wide
The humpback whale is a suitable demographic and genetic model for the management of less tractable species of baleen whales and for the general study of gene flow among long‐lived, mobile vertebrates in the marine ecosystem.
Low genetic variation among killer whales (Orcinus orca) in the eastern north Pacific and genetic differentiation between foraging specialists.
Low levels of genetic dispersal between foraging specialists and a pattern of genetic differentiation consistent with matrifocal population structure and small effective population size are suggested.
Isolation and interchange among insular spinner dolphin communities in the South Pacific revealed by individual identification and genetic diversity
A combined demographic and genetic approach is reported to describing the isolation and interchange of insular spinner dolphins among island communities of the Society Archipelago, French Polynesia, suggesting this genetic pattern is the result of metapopulation structure, based on numerous insular commu- nities evolutionarily connected through male and female gene flow.
Geographical variation in Hector's dolphin: Recognition of new subspecies of Cephalorhynchus hectori
Univariate and principal component analyses demonstrate that the North Island population of Hector's dolphin can be differentiated from the southern populations on the basis of several skeletal characters, plus genetic evidence of haplotype differences and absence of gene‐flow between populations are formally described.
Conservation of polymorphic simple sequence loci in cetacean species
The high conservation of non-coding sequences in whales simplifies the application of SSLP DNA fingerprinting in cetacean species, as primers designed for one species will often uncover variability in other species.
Detecting immigration by using multilocus genotypes.
  • B. Rannala, J. Mountain
  • Biology
    Proceedings of the National Academy of Sciences of the United States of America
  • 1997
The test has power to detect immigrant ancestors, for these data, up to two generations in the past even though the overall differentiation of allele frequencies among populations is low.
Fire and slice : palaeogeography for biogeography at New Zealand ’ s North Island / South Island juncture
A prominent feature of New Zealand biogeography is that species endemicity and diversity is not evenly distributed but shows an alternating pattern of latitudinal variation. Endemicity is generally
Bayesian inference of recent migration rates using multilocus genotypes.
A new Bayesian method that uses individual multilocus genotypes to estimate rates of recent immigration (over the last several generations) among populations is presented and allows genotype frequencies to deviate from Hardy-Weinberg equilibrium proportions within populations.
Conservation management in the face of uncertainty: effectiveness of four options for managing Hectors dolphin bycatch
New Zealand's endemic Hector's dolphins Cephalorhynchus hectori overlap with gillnet and trawl fisheries throughout their geographic range. The catch rate in commercial gillnets has been estimated