scholarly journals Genetic Management of Wild and Translocated Black Rhinoceros in South Africa’s KwaZulu-Natal Region

2021 ◽  
Author(s):  
◽  
Rosalynn Marie Anderson-Lederer
Keyword(s):  
Genetic Variation ◽  
Control Region ◽  
Allelic Diversity ◽  
Mtdna Control Region ◽  
Source Population ◽  
Management Scenarios ◽  
Genetic Management ◽  
Black Rhinoceros ◽  
Kwazulu Natal

<p>The African black rhinoceros (Diceros bicornis) is critically endangered. Like other megafauna, the species is managed in parks and is often translocated to expand their range into reserves where they have been extirpated. Management of genetic variation has been identified as an important consideration in long-term management plans for many wild and captive endangered species including black rhino. In this thesis I examined the contemporary levels of genetic variation within the black rhinoceros (D. b. minor) in KwaZulu-Natal (KZN), South Africa, and specifically the relict source population at Hluhluwe-iMfolozi Game Reserve (HiP), and how this information can be incorporated into management decisions to improve the long-term viability and persistence of the population. Previous studies have examined levels of genetic variation and differentiation among the three black rhino subspecies (D. b. minor, D. b. michaeli and D. b. bicornis) in an attempt to resolve their taxonomy and to establish baseline genetic assessments for managing populations. However, there has been a lack of genetic information based on the variable mitochondrial DNA (mtDNA) control region of the KZN metapopulation and a direct comparison of microsatellite variability between the D. b. minor populations of KZN and Zimbabwe.  The specific objectives of this study were to: (1) determine the DNA sequence of the mtDNA control region of three subspecies and estimate the level of variation within the HiP source and KZN metapopulation and compare the results with D. b. minor outside KZN and the other two subspecies; (2) use ten microsatellite DNA markers to estimate the levels of heterozygosity and allelic diversity in the HiP source and KZN metapopulation and compare results to previously published microsatellite data (specifically native Zimbabwe D. b. minor; and (3) use VORTEX Population Viability Analysis (PVA) and HiP vital rates to model the effects of increasing population size and supplementation, and investigate what management scenarios would be most effective for minimizing the loss of genetic variation caused by genetic drift with HiP...</p>

scholarly journals Genetic Management of Wild and Translocated Black Rhinoceros in South Africa’s KwaZulu-Natal Region

2021 ◽  
Author(s):  
◽  
Rosalynn Marie Anderson-Lederer
Keyword(s):  
Genetic Variation ◽  
Control Region ◽  
Allelic Diversity ◽  
Mtdna Control Region ◽  
Source Population ◽  
Management Scenarios ◽  
Genetic Management ◽  
Black Rhinoceros ◽  
Kwazulu Natal

<p>The African black rhinoceros (Diceros bicornis) is critically endangered. Like other megafauna, the species is managed in parks and is often translocated to expand their range into reserves where they have been extirpated. Management of genetic variation has been identified as an important consideration in long-term management plans for many wild and captive endangered species including black rhino. In this thesis I examined the contemporary levels of genetic variation within the black rhinoceros (D. b. minor) in KwaZulu-Natal (KZN), South Africa, and specifically the relict source population at Hluhluwe-iMfolozi Game Reserve (HiP), and how this information can be incorporated into management decisions to improve the long-term viability and persistence of the population. Previous studies have examined levels of genetic variation and differentiation among the three black rhino subspecies (D. b. minor, D. b. michaeli and D. b. bicornis) in an attempt to resolve their taxonomy and to establish baseline genetic assessments for managing populations. However, there has been a lack of genetic information based on the variable mitochondrial DNA (mtDNA) control region of the KZN metapopulation and a direct comparison of microsatellite variability between the D. b. minor populations of KZN and Zimbabwe.  The specific objectives of this study were to: (1) determine the DNA sequence of the mtDNA control region of three subspecies and estimate the level of variation within the HiP source and KZN metapopulation and compare the results with D. b. minor outside KZN and the other two subspecies; (2) use ten microsatellite DNA markers to estimate the levels of heterozygosity and allelic diversity in the HiP source and KZN metapopulation and compare results to previously published microsatellite data (specifically native Zimbabwe D. b. minor; and (3) use VORTEX Population Viability Analysis (PVA) and HiP vital rates to model the effects of increasing population size and supplementation, and investigate what management scenarios would be most effective for minimizing the loss of genetic variation caused by genetic drift with HiP...</p>

scholarly journals What can genomics tell us about the success of enhancement programs in anadromous Chinook salmon? A comparative analysis across four generations

2016 ◽  
Author(s):  
Charles D. Waters ◽  
Jeffrey J. Hard ◽  
Marine S.O. Brieuc ◽  
David E. Fast ◽  
Kenneth I. Warheit ◽  
...  
Keyword(s):  
Empirical Support ◽  
Source Population ◽  
Management Scenarios ◽  
Genetic Changes ◽  
Hatchery Fish ◽  
Genome Wide ◽  
Domestication Selection ◽  
Genetic Risks ◽  
Two Generations

Population enhancement through the release of cultured organisms can be an important tool for marine restoration. However, there has been considerable debate about whether releases effectively contribute to conservation and harvest objectives, and whether cultured organisms impact the fitness of wild populations. Pacific salmonid hatcheries on the West Coast of North America represent one of the largest enhancement programs in the world. Molecular-based pedigree studies on one or two generations have contributed to our understanding of the fitness of hatchery-reared individuals relative to wild individuals, and tend to show that hatchery fish have lower reproductive success. However, interpreting the significance of these results can be challenging because the long-term genetic and ecological effects of releases on supplemented populations are unknown. Further, pedigree studies have been opportunistic, rather than hypothesis driven, and have not provided information on “best case” management scenarios. Here, we present a comparative, experimental approach based on genome-wide surveys of changes in diversity in two hatchery lines founded from the same population. We demonstrate that gene flow with wild individuals can reduce divergence from the wild source population over four generations. We also report evidence for consistent genetic changes in a closed hatchery population that can be explained by both genetic drift and domestication selection. The results of this study suggest that genetic risks can be minimized over at least four generations with appropriate actions, and provide empirical support for a decision-making framework that is relevant to the management of hatchery populations.

High levels of mitochondrial DNA divergence within short-eared rock-wallaby (Petrogale brachyotis) populations in northern Australia

2010 ◽  
Vol 58 (2) ◽  
pp. 104 ◽  
Author(s):  
Wendy R. Telfer ◽  
Mark D. B. Eldridge
Keyword(s):  
Mitochondrial Dna ◽  
Gene Flow ◽  
Control Region ◽  
National Park ◽  
Sequence Divergence ◽  
Mtdna Control Region ◽  
Secondary Contact ◽  
Interspecific Hybridisation ◽  
Secondary Contact Zone

Most population genetics studies of rock-wallabies conducted to date have examined remnant colonies of threatened species inhabiting southern Australia. In this study we examined the natural pattern of contemporary and long-term gene flow among colonies of the widespread and abundant short-eared rock-wallaby, Petrogale brachyotis, in the relatively unmodified landscapes of Australia’s tropical north. We sampled 105 wallabies from seven colonies 1.2 km to 250 km apart. Mitochondrial DNA (mtDNA) control region sequence analysis was conducted on samples from all colonies and microsatellite analysis (10 loci) on samples from the three largest colonies. The microsatellite data revealed no evidence of inbreeding within colonies, but higher levels of genetic diversity were found in the Kakadu National Park population compared with the smaller, more isolated colonies at Litchfield National Park. Both the mtDNA and microsatellite results showed that populations of P. brachyotis are naturally highly structured even within this relatively intact landscape, with only limited contemporary and long-term gene flow between colonies more than 1.2 km apart. Nine mtDNA control region haplotypes were identified within the seven colonies. There were unusually high levels of sequence divergence (up to 6.9%) within colonies at Litchfield NP. This divergence suggests that multiple taxa may exist within what is currently recognised as P. brachyotis. Alternatively, if current taxonomy is correct, the high levels of divergence raise the possibility of ancestral isolation and divergence of populations in allopatry with subsequent admixture at a secondary contact zone. The possibility that these unusually divergent haplotypes result from introgressive interspecific hybridisation with the sympatric P. concinna appears unlikely.

scholarly journals Long-Term Experimental Evolution in Escherichia coli. VI. Environmental Constraints on Adaptation and Divergence

Genetics ◽  
1997 ◽  
Vol 146 (2) ◽  
pp. 471-479 ◽  
Author(s):  
Michael Travisano
Keyword(s):  
Escherichia Coli ◽  
Genetic Variation ◽  
Experimental Evolution ◽  
Population Genetic ◽  
Environmental Constraints ◽  
Asymmetric Pattern ◽  
Nutrient Environment ◽  
Mean Fitness ◽  
Population Genetic Variation

The effect of environment on adaptation and divergence was examined in two sets of populations of Escherichia coli selected for 1000 generations in either maltose- or glucose-limited media. Twelve replicate populations selected in maltose-limited medium improved in fitness in the selected environment, by an average of 22.5%. Statistically significant among-population genetic variation for fitness was observed during the course of the propagation, but this variation was small relative to the fitness improvement. Mean fitness in a novel nutrient environment, glucose-limited medium, improved to the same extent as in the selected environment, with no statistically significant among-population genetic variation. In contrast, 12 replicate populations previously selected for 1000 generations in glucose-limited medium showed no improvement, as a group, in fitness in maltose-limited medium and substantial genetic variation. This asymmetric pattern of correlated responses suggests that small changes in the environment can have profound effects on adaptation and divergence.

Sign in / Sign up

Export Citation Format

Share Document