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

@article{Hamner2012GeneticDA,
  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},
  year={2012},
  volume={13},
  pages={987-1002}
}
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…
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48 Citations

Low genetic diversity, limited gene flow and widespread genetic bottleneck effects in a threatened dolphin species, the Australian humpback dolphin
The Influence of Selection on MHC DQA and DQB Haplotypes in the Endemic New Zealand Hector’s and Māui Dolphins
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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
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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.
Low mtDNA diversity in a highly differentiated population of spinner dolphins (Stenella longirostris) from the Fernando de Noronha Archipelago, Brazil
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Genetic diversity and population structure of an island-associated population in the South Atlantic Ocean 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.
Microsatellite Markers Reveal Strong Genetic Structure in the Endemic Chilean Dolphin
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It is proposed that genetic differentiation may reflect ecological adaptation to the different habitat conditions and resource uses and the two genetic populations of this endemic and Near Threatened species should be considered as different conservation units with independent management strategies.
From Settlers to Subspecies: Genetic Differentiation in Commerson’s Dolphins Between South America and the Kerguelen Islands
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C. c. kerguelenensis may represent the most recent diversification step of Cephalorhynchus, where isolation from their source population is driving a process of incipient speciation, and is consistent with the model of post-glacial colonization of KI by South American C. b. commersonii.
Demographic collapse and low genetic diversity of the Irrawaddy dolphin population inhabiting the Mekong River
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Investigation of population structure and demographic history and phylogenetic analysis indicated reciprocal monophyly of Mekong River Orcaella haplotypes with respect to haplotypes from other populations, suggesting long-standing isolation of the Mekong dolphin population from other Orcalla populations.
Low abundance and probable decline of the critically endangered Maui's dolphin estimated by genotype capture–recapture
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The results of both models suggested that the population was likely to be declining across the study period, although this trend could not be confirmed with 95% confidence.
Mitochondrial diversity and inter-specific phylogeny among dolphins of the genus Stenella in the Southwest Atlantic Ocean
TLDR
It is demonstrated that ongoing gene flow is occurring among species of the genus Stenella reinforcing that this process could be one of the reasons for the confusing taxonomy and difficulties in elucidating phylogenetic relationships within this group.
Population Structure of Riverine and Coastal Dolphins Sotalia fluviatilis and Sotalia guianensis: Patterns of Nuclear and Mitochondrial Diversity and Implications for Conservation
TLDR
The results indicate that the small home ranges of these species may act to restrict gene flow between populations separated by relatively short distances, increasing the risk of extirpation of some localized populations in the future if existing threats are not minimized.
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