scholarly journals The effects of long-term translocation on population genetic structure of Ayu in Japan: Management implications for a recreationally fished iconic species

2021 ◽  
Author(s):  
Shuichi Kitada
Keyword(s):  
Genetic Diversity ◽  
Population Structure ◽  
Genetic Structure ◽  
Population Genetic Structure ◽  
Population Genetic ◽  
Recreational Fishing ◽  
Plecoglossus Altivelis ◽  
In The Wild ◽  
One Year

Ayu (Plecoglossus altivelis altivelis), an important freshwater fisheries resource and popular recreational fishing species, lives for only one year and has a single breeding season. To supplement increased recreational fishing demand, huge numbers of wild–born landlocked juvenile Ayu have been translocated from Lake Biwa into most Japanese rivers for more than 50 generations. Hatchery-born amphidromous fish (including amphidromous and landlocked form hybrids) have also been released for many generations. Hatchery–born fish have low survival and maladapted behaviour in the wild. Landlocked and amphidromous forms of Ayu easily hybridise, but survival of progeny of landlocked forms is very low in seawater. Repeat backcrossing may cause introgression of landlocked forms into amphidromous populations, but this has not been previously identified. Study objectives using genetic data from Ayu from 118 locations throughout the distribution of this species in Japan are to describe contemporary population structure, genetic diversity, and admixture proportions of Ayu forms in populations, and to evaluate how human-induced translocation has affected population genetic structure. The analyses of published genotypes of 12 microsatellite markers provide strong evidence for very high gene flow between populations, but population structure has been retained in several regions, and several populations are nested. Genetic diversity is surprisingly homogeneous. Hybridisation between landlocked and amphidromous forms has occurred in all populations, with a mean hybrid proportion (± standard deviation) of 37 ± 10%, ranging 15%–60%. Results are discussed in relation to the conservation and management of this species. Recommendations are made to reduce translocation and hatchery releases, by establishing rivers and/or areas in every prefecture where translocation does not occur. Release of juveniles is of value for short–term management objectives, but management of spawning escapements, and improving the spawning and nursery habitat are important for this species long–term sustainability.

scholarly journals Genomic epidemiology ofMycobacterium bovisinfection in sympatric badger and cattle populations in Northern Ireland

2021 ◽  
Author(s):  
Assel Akhmetova ◽  
Jimena Guerrero ◽  
Paul McAdam ◽  
Liliana C.M. Salvador ◽  
Joseph Crispell ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Spatial Distribution ◽  
Genetic Structure ◽  
Northern Ireland ◽  
Population Genetic Structure ◽  
Population Genetic ◽  
Transmission Dynamics ◽  
Data Set ◽  
Hair Samples ◽  
Disease Persistence

AbstractBackgroundBovine tuberculosis (bTB) is a costly epidemiologically complex, multi-host, endemic disease. Lack of understanding of transmission dynamics may undermine eradication efforts. Pathogen whole genome sequencing improves epidemiological inferences, providing a means to determine the relative importance of inter- and intra- species host transmission for disease persistence. We sequenced an exceptional data set of 619Mycobacterium bovisisolates from badgers and cattle in a 100km2bTB ‘hotspot’ in Northern Ireland. Historical molecular subtyping data permitted the targeting of an endemic pathogen lineage, whose long-term persistence provided a unique opportunity to study disease transmission dynamics in unparalleled detail. Additionally, to assess whether badger population genetic structure was associated with the spatial distribution of pathogen genetic diversity, we microsatellite genotyped hair samples from 769 badgers trapped in this area.ResultsGraph transmission tree methods and structured coalescent analyses indicated the majority of bacterial diversity was found in the local cattle population. Results pointed to transmission from cattle to badger being more common than badger to cattle. Furthermore, the presence of significant badger population genetic structure in the landscape was not associated with the spatial distribution ofM. bovisgenetic diversity, suggesting that badger-to-badger transmission may not be a key determinant of disease persistence.SignificanceOur data were consistent with badgers playing a smaller role in the maintenance ofM. bovisinfection in this study site, compared to cattle. Comparison to other areas suggests thatM. bovistransmission dynamics are likely to be context dependent, and the role of wildlife difficult to generalise.

scholarly journals Diverging Genetic Structure of Coexisting Populations of the Black Storm-Petrel and the Least Storm-Petrel in the Gulf of California

2020 ◽  
Vol 13 ◽  
pp. 194008292094917
Author(s):  
Misael D. Mancilla-Morales ◽  
Santiago Romero-Fernández ◽  
Araceli Contreras-Rodríguez ◽  
José J. Flores-Martínez ◽  
Víctor Sánchez-Cordero ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Genetic Structure ◽  
Population Genetic Structure ◽  
Mate Selection ◽  
Gulf Of California ◽  
Population Genetic ◽  
Life Histories ◽  
Gene Diversity ◽  
Isolation By Distance ◽  
Storm Petrel

Estimations on the influence of evolutionary and ecological forces as drivers of population gene diversity and genetic structure have been performed on a growing number of colonial seabirds, but many remain poorly studied. In particular, the population genetic structure of storm-petrels (Hydrobatidae) has been evaluated in only a few of the 24 recognized species. We assessed the genetic diversity and population structure of the Black Storm-Petrel ( Hydrobates melania) and the Least Storm-Petrel ( Hydrobates microsoma) in the Gulf of California. The two species were selected because they are pelagic seabirds with comparable ecological traits and breeding grounds. Recent threats such as introduced species of predators and human disturbance have resulted in a decline of many insular vertebrate populations in this region and affected many different aspects of their life histories (ranging from reproductive success to mate selection), with a concomitant loss of genetic diversity. To elucidate to what extent the population genetic structure occurs in H. melania and H. microsoma, we used 719 base pairs from the mitochondrial cytochrome oxidase c subunit I gene. The evaluation of their molecular diversity, genetic structure, and gene flow were performed through diversity indices, analyses of molecular and spatial variance, and isolation by distance (IBD) across sampling sites, respectively. The population genetic structure (via AMOVA and SAMOVA) and isolation by distance (pairwise p-distances and FST/1– FST (using ΦST) were inferred for H. microsoma. However, for H. melania evidence was inconclusive. We discuss explanations leading to divergent population genetic structure signatures in these species, and the consequences for their conservation.

scholarly journals Oceanographic features and limited dispersal shape the population genetic structure of the vase sponge Ircinia campana in the Greater Caribbean

Heredity ◽  
2020 ◽  
Vol 126 (1) ◽  
pp. 63-76
Author(s):  
Sarah M. Griffiths ◽  
Mark J. Butler ◽  
Donald C. Behringer ◽  
Thierry Pérez ◽  
Richard F. Preziosi
Keyword(s):  
Genetic Diversity ◽  
Genetic Structure ◽  
Population Genetic Structure ◽  
Larval Dispersal ◽  
Population Genetic ◽  
Spatial Genetic Structure ◽  
Florida Keys ◽  
The United States ◽  
Limited Dispersal ◽  
Mass Mortalities

AbstractUnderstanding population genetic structure can help us to infer dispersal patterns, predict population resilience and design effective management strategies. For sessile species with limited dispersal, this is especially pertinent because genetic diversity and connectivity are key aspects of their resilience to environmental stressors. Here, we describe the population structure of Ircinia campana, a common Caribbean sponge subject to mass mortalities and disease. Microsatellites were used to genotype 440 individuals from 19 sites throughout the Greater Caribbean. We found strong genetic structure across the region, and significant isolation by distance across the Lesser Antilles, highlighting the influence of limited larval dispersal. We also observed spatial genetic structure patterns congruent with oceanography. This includes evidence of connectivity between sponges in the Florida Keys and the southeast coast of the United States (>700 km away) where the oceanographic environment is dominated by the strong Florida Current. Conversely, the population in southern Belize was strongly differentiated from all other sites, consistent with the presence of dispersal-limiting oceanographic features, including the Gulf of Honduras gyre. At smaller spatial scales (<100 km), sites showed heterogeneous patterns of low-level but significant genetic differentiation (chaotic genetic patchiness), indicative of temporal variability in recruitment or local selective pressures. Genetic diversity was similar across sites, but there was evidence of a genetic bottleneck at one site in Florida where past mass mortalities have occurred. These findings underscore the relationship between regional oceanography and weak larval dispersal in explaining population genetic patterns, and could inform conservation management of the species.

Genetic diversity, Population Genetic Structure and Conservation Management of Spanish Verata Goat Breed

2020 ◽  
Vol 187 ◽  
pp. 106106
Author(s):  
M. Martínez-Trancón ◽  
J.C. Parejo ◽  
A. Rabasco ◽  
P. Padilla ◽  
J.A. Padilla
Keyword(s):  
Genetic Diversity ◽  
Genetic Structure ◽  
Population Genetic Structure ◽  
Population Genetic ◽  
Conservation Management ◽  
Goat Breed

scholarly journals Birds are islands for parasites

2014 ◽  
Vol 10 (8) ◽  
pp. 20140255 ◽  
Author(s):  
Jennifer A. H. Koop ◽  
Karen E. DeMatteo ◽  
Patricia G. Parker ◽  
Noah K. Whiteman
Keyword(s):  
Population Structure ◽  
Genetic Structure ◽  
Population Genetic Structure ◽  
Population Genetic ◽  
Evolutionary Biology ◽  
Isolation By Distance ◽  
Spatial Scales ◽  
Island Populations ◽  
Louse Species ◽  
Parasite Populations

Understanding the mechanisms driving the extraordinary diversification of parasites is a major challenge in evolutionary biology. Co-speciation, one proposed mechanism that could contribute to this diversity is hypothesized to result from allopatric co-divergence of host–parasite populations. We found that island populations of the Galápagos hawk ( Buteo galapagoensis ) and a parasitic feather louse species ( Degeeriella regalis ) exhibit patterns of co-divergence across variable temporal and spatial scales. Hawks and lice showed nearly identical population genetic structure across the Galápagos Islands. Hawk population genetic structure is explained by isolation by distance among islands. Louse population structure is best explained by hawk population structure, rather than isolation by distance per se , suggesting that lice tightly track the recent population histories of their hosts. Among hawk individuals, louse populations were also highly structured, suggesting that hosts serve as islands for parasites from an evolutionary perspective. Altogether, we found that host and parasite populations may have responded in the same manner to geographical isolation across spatial scales. Allopatric co-divergence is likely one important mechanism driving the diversification of parasites.

Multilocus genotypic data reveal high genetic diversity and low population genetic structure of Iranian indigenous sheep

2016 ◽  
Vol 47 (4) ◽  
pp. 463-470 ◽  
Author(s):  
S. M. F. Vahidi ◽  
M. O. Faruque ◽  
M. Falahati Anbaran ◽  
F. Afraz ◽  
S. M. Mousavi ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Genetic Structure ◽  
Population Genetic Structure ◽  
Population Genetic ◽  
High Genetic Diversity ◽  
Indigenous Sheep
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