Genetic structure of the western pygmy possum, Cercartetus concinnus Gould (Marsupialia: Burramyidae) based on mitochondrial DNA

2007 ◽  
Vol 29 (2) ◽  
pp. 191 ◽  
Author(s):  
A.J.L. Pestell ◽  
S.J.B. Cooper ◽  
K. Saint ◽  
S. Petit
Keyword(s):  
Western Australia ◽  
South Australia ◽  
Disjunct Distribution ◽  
Genetic Connectivity ◽  
Phylogeographic Structure ◽  
Isolated Populations ◽  
Evolutionarily Significant Unit ◽  
Eastern Australia ◽  
Wide Range ◽  
The Impact

Cercartetus concinnus Gould (Marsupialia: Burramyidae) has a spatially disjunct distribution, with a broad stretch of saltbush on the Nullarbor Plain forming an apparent barrier between the population: one in southern Western Australia, and another in south-eastern Australia, encompassing South Australia, Victoria, and New South Wales. This disjunct distribution and slight differences in morphology between western and eastern populations have led to conjecture about the taxonomy of this species. This study assessed the taxonomic status of C. concinnus across southern Australia. Analyses using the mitochondrial (mtDNA) ND4 gene showed little phylogeographic structure throughout the wide range of C. concinnus in southern Australia; closely related haplotypes (~0.1% sequence divergence) had a wide distribution from Western Australia to South Australia, suggesting recent genetic connectivity. These data indicate that C. concinnus populations represent a single taxonomic unit (Evolutionarily Significant Unit) throughout the geographic range. Further research is required to assess the impact of recent population fragmentation and whether an erosion of genetic variation in isolated populations has occurred.

Conservation units and phylogeographic structure of an arboreal marsupial, the yellow-bellied glider (Petaurus australis)

2006 ◽  
Vol 54 (5) ◽  
pp. 305 ◽  
Author(s):  
Meredeth Brown ◽  
Huw Cooksley ◽  
Susan M. Carthew ◽  
Steven J. B. Cooper
Keyword(s):  
South Australia ◽  
Type Specimen ◽  
Disjunct Distribution ◽  
Phylogeographic Structure ◽  
Restricted Gene Flow ◽  
Ecological Data ◽  
Isolated Populations ◽  
Conservation Units ◽  
Evolutionarily Significant Unit ◽  
Petaurus Australis

Subspecific status has often been used as a surrogate for conservation unit, but does not always reflect intraspecific lineages with different evolutionary histories. One contentious case of subspecific classification occurs in the yellow-bellied glider (Petaurus australis), a marsupial species showing considerable decline in population size and requiring conservation management. Our aim was to assess the current subspecific status of populations and define units of conservation using a combination of phylogeographical analyses of mitochondrial DNA and morphological analyses. Analyses of the mitochondrial ND4 gene provided evidence for significant phylogeographic structure within P. australis. Isolated populations in north Queensland (NQ) and Victoria/South Australia were genetically distinct from populations in New South Wales and southern Queensland. Morphological analyses provided little evidence for discrimination of populations, although NQ specimens were generally smaller in size than southern forms. Our analyses do not support the classification of subspecies P. a. reginae for the original type specimen from southern Queensland. Taking into account other behavioural and ecological data, and the disjunct distribution of NQ populations from southern populations, we propose that the NQ population represents a distinct Evolutionarily Significant Unit, a lineage showing highly restricted gene flow from the rest of the species.

Potential adaptation zones for temperate pasture species as constrained by climate: a knowledge-based logical modelling approach

1996 ◽  
Vol 47 (7) ◽  
pp. 1095 ◽  
Author(s):  
MJ Hill
Keyword(s):  
Soil Ph ◽  
Western Australia ◽  
Perennial Ryegrass ◽  
South Australia ◽  
Subterranean Clover ◽  
Climate Data ◽  
Validation Data ◽  
Knowledge Based ◽  
Eastern Australia ◽  
Potential Adaptation

Potential adaptation zones were modelled for major temperate pasture species using climate data and knowledge-based logical rules. A GIs database was constructed using a 0.025 degree digital elevation model and the Australian Climate Surfaces to create layers of monthly mean climate data for Australia. Soil pH maps for New South Wales, Victoria, and south-eastern South Australia were digitised and added to the database. Simple models using logical operators were constructed using estimates of temperature and aridity thresholds for the main temperate pasture species. The logical models were executed using primary and derived climate layers to create raster maps of potential adaptation zones for pasture species in eastern and south-western Australia. Areas of adaptation on freehold/leasehold land were expressed relative to a potential temperate pasture adaptation zone described by the lower (arid) limit of annual legume adaptation in temperate Australia and the northern limit of lucerne adaptation. Potential adaptation within this area ranged from 66% for lucerne down to <20% for perennial ryegrass in eastern Australia, and 93% for subterranean clover down to zero for perennial ryegrass in south-western Australia. Utility of the species adaptation zones could be enhanced using soil pH maps: a zone for serradella in NSW was refined by restricting adaptation to areas of climatic suitability with low soil pH. Maps for lucerne and Mount Barker subterranean clover showed good agreement with validation data for NSW. The zones may be readily adjusted by simple changes to parameter values in the algorithms. This knowledge-based approach has potential as an aid to targeting resources for plant improvement or to provide advice for more efficient utilisation of existing commercial pasture plants.

Corrigendum to: The impact of rabbit haemorrhagic disease on wild rabbit (Oryctolagus cuniculus) populations in Queensland

2004 ◽  
Vol 31 (6) ◽  
pp. 651
Author(s):  
G. Story ◽  
J. Scanlan ◽  
R. Palmer ◽  
D. Berman
Keyword(s):  
Biological Control Agent ◽  
South Australia ◽  
Control Agent ◽  
Wild Rabbit ◽  
Isolated Populations ◽  
Rabbit Haemorrhagic Disease ◽  
Northern Edge ◽  
The Mean ◽  
Haemorrhagic Disease ◽  
The Impact

Rabbit haemorrhagic disease virus (RHDV) escaped from quarantine facilities on Wardang Island in September 1995 and spread through South Australia to Queensland by December 1995. To determine the impact of this biological control agent on wild rabbit populations in Queensland, shot sample and spotlight count data were collected at six sites. RHDV spread across Queensland from the south-west to the east at a rate of at least 91 km month–1 between October 1995 and October 1996. The initial impact on rabbit density appeared highly variable, with an increase of 81% (255 ± 79 (s.e.) to 385 ± 73 rabbits km–2) at one site and a decrease of 83% (129 ± 27 to 22 ± 18 rabbits km–2) at another during the first outbreak. However, after 30 months of RHDV activity, counts were at least 90% below counts conducted before RHDV arrived. Using a population model to account for environmental conditions, the mean suppression of rabbit density caused by rabbit haemorrhagic disease (RHD) was estimated to be 74% (ranging from 43% to 94% between sites). No outbreaks were observed when the density of susceptible rabbits was lower than 12 km–2. Where rabbit density remains low for long periods RHDV may not persist. This is perhaps most likely to occur in the isolated populations towards the northern edge of the range of rabbits in Australia. RHDV may have to be reintroduced into these populations. Further south in areas more suitable for rabbits, RHDV is more likely to persist, resulting in a high density of immune rabbits. In such areas conventional control techniques may be more important to enhance the influence of RHD.

Systematics of the Australian species of Dictyopteris (Dictyotales, Phaeophyceae)

2000 ◽  
Vol 13 (2) ◽  
pp. 283 ◽  
Author(s):  
J. A. Phillips
Keyword(s):  
Cell Layer ◽  
South Australia ◽  
Reproductive Organs ◽  
Cortical Layer ◽  
Tropical Species ◽  
Species Discrimination ◽  
Isolated Populations ◽  
Australian Species ◽  
Eastern Australia ◽  
Reproductive Characters

Eleven species of Dictyopteris are recognised for Australia. The tropical species D. australis (Sonder) Askenasy, D. deliculata Lamouroux, D. plagiogramma (Montagne) Vickers, D. repens (Okamura) B&oslash;rgesen, D. serrata (Areschoug) Hoyt and D. woodwardia (R.Brown ex Turner) C.Agardh are recorded for warmer coasts, although isolated populations of D. australis occur in the Gulfs region of South Australia. Dictyopteris acrostichoides (J.Agardh) Bornet and D. crassinervia (Zanardini) Schmidt are endemic to eastern Australia, with D. acrostichoides also extending to the eastern end of the southern coast. Dictyopteris gracilis Womersley and D. muelleri (Sonder) Reinbold occur on temperate southwestern and southern coasts. The west coast species Dictyopteris secundispiralis J.A.Phillips sp. nov. is described, and D. nigricans Womersley is reduced to a taxonomic synonym ofD. muelleri. Detailed comparative studies undertaken on these species have identified several new taxonomically-informative characters useful for generic circumscription and species discrimination. Thallus branches which have a cortical layer composed of large cuboidal cells and reproductive organs scattered in fertile zones are additional characters which characterise the genus. Australian species of Dictyopteris are now well defined by differences in several distinctive vegetative and reproductive characters such as thallus morphology, blade cell layer number, structure of the thallus apex, presence of marginal teeth and lateral veins, distribution and structure of hair bundles, sporangia, oogonia and antheridial sori.

Marine and estuarine phylogeography of the coasts of south-eastern Australia

2016 ◽  
Vol 67 (11) ◽  
pp. 1597 ◽  
Author(s):  
D. J. Colgan
Keyword(s):  
South Australia ◽  
Rocky Intertidal ◽  
Phylogeographic Structure ◽  
Subtidal Zone ◽  
South Eastern ◽  
South Wales ◽  
Eastern Australia ◽  
North Eastern ◽  
Genetic Techniques ◽  
South Eastern Australia

Understanding a region’s phylogeography is essential for an evolutionary perspective on its biological conservation. This review examines the phylogeographic structures in south-eastern Australia that have been revealed by mitochondrial DNA sequencing and other genetic techniques and examines whether they can be explained by known factors. The review covers species that occur in the intertidal zone or, even infrequently, in the shallow subtidal zone. The coasts most frequently associated with phylogeographic structure are the boundaries between the Peronian and Maugean biogeographical provinces in southern New South Wales and the Maugean and Flindersian provinces in South Australia, the areas in Victoria and north-eastern Tasmania separated by the Bassian Isthmus at glacial maxima, long sandy stretches without rocky intertidal habitat on the Ninety Mile Beach in Victoria and the Younghusband Peninsula–Coorong in South Australia, southern Tasmania and Bass Strait, which acts as a barrier for littoral species.

Colony relocation of Greater Crested Terns Thalasseus bergii in Bass Strait, south-eastern Australia

2020 ◽  
Vol 37 ◽  
pp. 166-171
Author(s):  
Aymeric Fromant ◽  
◽  
Yonina Eizenberg ◽  
Rosalind Jessop ◽  
Arnaud Lec’hvien ◽  
...  
Keyword(s):  
Prey Availability ◽  
South Australia ◽  
Barrier Islands ◽  
Breeding Population ◽  
Storm Events ◽  
Jack Mackerel ◽  
Seabird Species ◽  
Eastern Australia ◽  
Environmental Variations ◽  
The Impact

A newly established Greater Crested Tern Thalasseus bergii colony was observed on Kanowna Island, northern Bass Strait, in December 2019 and was monitored through January 2020. A maximum of 532 ± 28 nests was counted,representing ~15–20% of the known northern Bass Strait breeding population. Resightings of 69 leg-banded individuals (from 3 to 24 years of age) demonstrated that founding individuals originated from colonies in Victoria [The Nobbies on Phillip Island (54%), Corner Inlet Barrier Islands (39%), Mud Islands in Port Phillip Bay (6%)] and one individual from South Australia. Breeding began 2 months later than usual for northern Bass Strait, perhaps because the birds only moved to Kanowna Island after failed nesting attempts elsewhere (Corner Inlet and Phillip Island). Individuals were observed to mainly feed their chicks with Barracouta Thyrsites atun and Jack Mackerel Trachurus declivis, contrasting with the usual predominance of Australian Anchovy Engraulis australis in the diet of this species in the Bass Strait region. This relocation may result from local changes in prey availability and/or a combination of potential human disturbance, predation and storm events. The recent 50% decrease in the number of breeding Greater Crested Terns in Victoria suggests substantial changes in the regional environmental conditions, highlighting the importance of understanding the impact of environmental variations on seabird species.

scholarly journals Jet-Setting Koalas SpreadCryptococcus gattiiVGII in Australia

mSphere ◽  
2019 ◽  
Vol 4 (3) ◽  
Author(s):  
Laura J. Schmertmann ◽  
Patrizia Danesi ◽  
Juan Monroy-Nieto ◽  
Jolene Bowers ◽  
David M. Engelthaler ◽  
...  
Keyword(s):  
Western Australia ◽  
Host Species ◽  
Cryptococcus Gattii ◽  
Genomic Diversity ◽  
Molecular Type ◽  
Phascolarctos Cinereus ◽  
Content Type ◽  
Eastern Australia ◽  
Wide Range ◽  
Sporadic Cases

ABSTRACTCryptococcus gattiimolecular type VGII is one of the etiologic agents of cryptococcosis, a systemic mycosis affecting a wide range of host species. Koalas (Phascolarctos cinereus) exhibit a comparatively high prevalence of cryptococcosis (clinical and subclinical) and nasal colonization, particularly in captivity. In Australia, disease associated withC. gattiiVGII is typically confined to Western Australia and the Northern Territory (with sporadic cases reported in eastern Australia), occupying an enigmatic ecologic niche. A cluster of cryptococcosis in captive koalas in eastern Australia (five confirmed cases, a further two suspected), caused predominantly byC. gattiiVGII, was investigated by surveying for subclinical disease, culturing koala nasal swabs and environmental samples, and genotyping cryptococcal isolates.URA5restriction fragment length polymorphism analysis, multilocus sequence typing (MLST), and whole-genome sequencing (WGS) provided supportive evidence that the transfer of koalas from Western Australia and subsequently between several facilities in Queensland spread VGII into uncontaminated environments and environments in whichC. gattiiVGI was endemic. MLST identified VGII isolates as predominantly sequence type 7, while WGS further confirmed a limited genomic diversity and revealed a basal relationship with isolates from Western Australia. We hypothesize that this represents a founder effect following the introduction of a koala from Western Australia. Our findings suggest a possible competitive advantage forC. gattiiVGII over VGI in the context of this captive koala environment. The ability of koalas to seedC. gattiiVGII into new environments has implications for the management of captive populations and movements of koalas between zoos.IMPORTANCECryptococcus gattiimolecular type VGII is one of the causes of cryptococcosis, a severe fungal disease that is acquired from the environment and affects many host species (including humans and koalas). In Australia, disease caused byC. gattiiVGII is largely confined to western and central northern parts of the country, with sporadic cases reported in eastern Australia. We investigated an unusual case cluster of cryptococcosis, caused predominantly byC. gattiiVGII, in a group of captive koalas in eastern Australia. This research identified that the movements of koalas between wildlife parks, including an initial transfer of a koala from Western Australia, introduced and subsequently spreadC. gattiiVGII in this captive environment. The spread of this pathogen by koalas could also impact other species, and these findings are significant in the implications they have for the management of koala transfers and captive environments.

Distribution of the tammar, Macropus eugenii, and the relationships of populations as determined by cranial morphometrics

1991 ◽  
Vol 18 (5) ◽  
pp. 625 ◽  
Author(s):  
WE Poole ◽  
JT Wood ◽  
NG Simms
Keyword(s):  
New Zealand ◽  
Western Australia ◽  
Spanning Trees ◽  
South Australia ◽  
Canonical Variate ◽  
Isolated Populations ◽  
Mahalanobis Distances ◽  
Island Populations ◽  
Morphometric Analyses ◽  
Subsequent Calculation

Apparently once widespread throughout dense thickets in south-western Australia, the tammar is now much restricted in its distribution. On mainland Australia, isolated populations still persist in Western Australia, but in South Australia, where there is little remaining evidence to confirm that it extended beyond Eyre Peninsula, the wallaby is probably close to extinction. All originally recorded populations on five islands in Western Australia remain, but in South Australia all natural island populations, other than those on Kangaroo I., appear to be extinct. Morphometric analyses of crania representative of most known populations provide a means of assessing their relationships. Canonical variate analysis, the derivation of Mahalanobis distances and subsequent calculation of minimum spanning trees supported the existence of affinities within three major regional groups-a group predominantly from Western Australia, a group from Kangaroo and Greenly Is, South Australia, and a group from New Zealand-all apparently related via a population from Eyre Peninsula, presumably representative of a former widespread mainland population. By cranial criteria, feral tammars established in New Zealand are South Australian in origin although probably not introduced from Kangaroo I.

Impact of mortality, possibly due to herpesvirus, on pilchard Sardinops sagax stocks along the south coast of Western Australia in 1998-99

2000 ◽  
Vol 51 (6) ◽  
pp. 601 ◽  
Author(s):  
D. J. Gaughan ◽  
R. W. Mitchell ◽  
S. J. Blight
Keyword(s):  
Western Australia ◽  
Total Mortality ◽  
Simulation Models ◽  
Mortality Rates ◽  
Sea Surface ◽  
Sea Floor ◽  
Wide Range ◽  
The Mean ◽  
The Difference ◽  
The Impact

During progression of a mass mortality of Australian pilchards in late 1998 and early 1999, quantities of dead pilchards on the sea-surface, sea-floor and along beaches were estimated in three regions along southern Western Australia (WA) by use of transects. Total mortality was estimated at 17 590, 11193 and 144.4 t for Esperance, Bremer Bay and Albany respectively. Mortality rates at Esperance and Bremer Bay were similar at 74.5% and 64.7% respectively, with a mean of 69.6%. In contrast, estimated mortality at Albany was only 2.4%. Although the difference in total mortality between regions is probably related to differences in stock size, as determined by simulation models, the much lower estimate for Albany is probably an artefact of an over-estimated pilchard biomass and not due to large differences in actual mortality rates. Variability in estimates of both pilchard biomass and quantities killed resulted in a wide range of estimated mortality rates, with lower estimates for Esperance and Bremer Bay of 28.0% and 22.9% respectively. This represents a significant decline in the breeding stock of WA pilchards. If the impact was closer to the mean (69.6%), then pilchard stocks in WA are severely depressed.

scholarly journals Patterns of genetic structuring at the northern limits of the Australian smelt (Retropinna semoni) cryptic species complex

PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e4654 ◽  
Author(s):  
Md Rakeb-Ul Islam ◽  
Daniel J. Schmidt ◽  
David A. Crook ◽  
Jane M. Hughes
Keyword(s):  
Population Structure ◽  
Genetic Structure ◽  
Cryptic Species ◽  
Species Complex ◽  
Gene Tree ◽  
Genetic Connectivity ◽  
Phylogeographic Structure ◽  
Genetic Structuring ◽  
Eastern Australia ◽  
Cryptic Species Complex

Freshwater fishes often exhibit high genetic population structure due to the prevalence of dispersal barriers (e.g., waterfalls) whereas population structure in diadromous fishes tends to be weaker and driven by natal homing behaviour and/or isolation by distance. The Australian smelt (Retropinnidae:Retropinna semoni) is a native fish with a broad distribution spanning inland and coastal drainages of south-eastern Australia. Previous studies have demonstrated variability in population genetic structure and movement behaviour (potamodromy, facultative diadromy, estuarine residence) across the southern part of its geographic range. Some of this variability may be explained by the existence of multiple cryptic species. Here, we examined genetic structure of populations towards the northern extent of the species’ distribution, using ten microsatellite loci and sequences of the mitochondrial cytbgene. We tested the hypothesis that genetic connectivity among rivers should be low due to a lack of dispersal via the marine environment, but high within rivers due to dispersal. We investigated populations corresponding with two putative cryptic species, SEQ-North (SEQ-N), and SEQ-South (SEQ-S) lineages occurring in south east Queensland drainages. These two groups formed monophyletic clades in the mtDNA gene tree and among river phylogeographic structure was also evident within each clade. In agreement with our hypothesis, highly significant overallFSTvalues suggested that both groups exhibit very low dispersal among rivers (SEQ-SFST= 0.13; SEQ-NFST= 0.27). Microsatellite data indicated that connectivity among sites within rivers was also limited, suggesting dispersal may not homogenise populations at the within-river scale. Northern groups in the Australian smelt cryptic species complex exhibit comparatively higher among-river population structure and smaller geographic ranges than southern groups. These properties make northern Australian smelt populations potentially susceptible to future conservation threats, and we define eight genetically distinct management units along south east Queensland to guide future conservation management. The present findings at least can assist managers to plan for effective conservation and management of different fish species along coastal drainages of south east Queensland, Australia.

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