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Peter Dann - One of the best experts on this subject based on the ideXlab platform.
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Seasonal variation and annual trends of metals and metalloids in the blood of the Little Penguin (Eudyptula Minor)
Marine pollution bulletin, 2016Co-Authors: Annett Finger, Peter Dann, Jennifer L. Lavers, Dayanthi Nugegoda, John D. Orbell, Carol ScarpaciAbstract:Little Penguins (Eudyptula Minor) are high-trophic coastal feeders and are effective indicators of bioavailable pollutants in their foraging zones. Here, we present concentrations of metals and metalloids in blood of 157 Little Penguins, collected over three years and during three distinct seasons (breeding, moulting and non-breeding) at two locations: the urban St Kilda colony and the semi-rural colony at Phillip Island, Victoria, Australia. Penguin metal concentrations were foremostly influenced by location (St Kilda > Phillip Island for non-essential elements) and differed among years and seasons at both locations, reflecting differences in seasonal metal bioaccumulation or seasonal exposure through prey. Mean blood mercury concentrations showed an increasing annual trend and a negative correlation with flipper length at St Kilda. Notably, this study is the first to report on blood metal concentrations during the different stages of moult, showing the mechanism of non-essential metal mobilisation and detoxification.
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The Little Penguin (Eudyptula Minor) as an indicator of coastal trace metal pollution
Environmental pollution (Barking Essex : 1987), 2015Co-Authors: Annett Finger, Peter Dann, Jennifer L. Lavers, Dayanthi Nugegoda, John D. Orbell, Bruce Robertson, Carol ScarpaciAbstract:Monitoring trace metal and metalloid concentrations in marine animals is important for their conservation and could also reliably reflect pollution levels in their marine ecosystems. Concentrations vary across tissue types, with implications for reliable monitoring. We sampled blood and moulted feathers of the Little Penguin (Eudyptula Minor) from three distinct colonies, which are subject to varying levels of anthropogenic impact. Non-essential trace metal and metalloid concentrations in Little Penguins were clearly linked to the level of industrialisation adjacent to the respective foraging zones. This trend was more distinct in blood than in moulted feathers, although we found a clear correlation between blood and feathers for mercury, lead and iron. This study represents the first reported examination of trace metals and metalloids in the blood of any penguin species and demonstrates that this high trophic feeder is an effective bioindicator of coastal pollution.
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Epidemiology and molecular phylogeny of Babesia sp. in Little Penguins Eudyptula Minor in Australia
International journal for parasitology. Parasites and wildlife, 2015Co-Authors: Ralph Eric Thijl Vanstreels, Eric J. Woehler, Peter Dann, Annett Finger, Valeria Ruoppolo, Peter Vertigan, Nicholas Carlile, David Priddel, Kimberly Vinette Herrin, Paul P. ThompsonAbstract:Blood parasites are potential threats to the health of penguins and to their conservation and management. Little penguins Eudyptula Minor are native to Australia and New Zealand, and are susceptible to piroplasmids (Babesia), hemosporidians (Haemoproteus, Leucocytozoon, Plasmodium) and kinetoplastids (Trypanosoma). We studied a total of 263 wild little penguins at 20 sites along the Australian southeastern coast, in addition to 16 captive-bred little penguins. Babesia sp. was identified in seven wild little penguins, with positive individuals recorded in New South Wales, Victoria and Tasmania. True prevalence was estimated between 3.4% and 4.5%. Only round forms of the parasite were observed, and gene sequencing confirmed the identity of the parasite and demonstrated it is closely related to Babesia poelea from boobies (Sula spp.) and B. uriae from murres (Uria aalge). None of the Babesia-positive penguins presented signs of disease, confirming earlier suggestions that chronic infections by these parasites are not substantially problematic to otherwise healthy little penguins. We searched also for kinetoplastids, and despite targeted sampling of little penguins near the location where Trypanosoma Eudyptulae was originally reported, this parasite was not detected.
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Variation in innate immune function during incubation, chick-rearing and moult in Little Penguins (Eudyptula Minor)
Emu - Austral Ornithology, 2015Co-Authors: Jessica K. Evans, Peter Dann, T. L. FrankelAbstract:Physiologically demanding and energetically expensive life-events, such as incubation, chick-rearing and moult, may cause a trade-off with costly immune defences and, in turn, decrease immune function. We examined innate immunity in Little Penguins (Eudyptula Minor) during the physiologically demanding periods of incubation, chick-guarding, chick-rearing and moult using a bacterial-killing assay and white blood-cell counts. The capacity of individuals to kill Escherichia coli varied significantly in relation to life-stage, with bacterial killing significantly higher during incubation compared with late chick-rearing, the most energetically expensive period in the annual cycle of Little Penguins. The elevated bacterial-killing capacity during nesting stages could be particularly beneficial for protection from the presumed high pathogen (bacterial) loads in nests. However, this relationship remains to be tested. Counts of white blood cells varied during breeding but were significantly higher in chicks compared to adults during guarding and post-guarding stages, and significantly higher at the end of moult compared to all other stages, which could indicate inflammation from infection, or dehydration. These results suggest that immune function may be adversely affected during energetically demanding life-stages but may also offer protection from bacteria encountered in the nesting environment.
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semivarying coefficient models for capture recapture data colony size estimation for the little penguin Eudyptula Minor
Bellman Prize in Mathematical Biosciences, 2014Co-Authors: Jakub Stoklosa, Peter Dann, Richard HugginsAbstract:Abstract To accommodate seasonal effects that change from year to year into models for the size of an open population we consider a time-varying coefficient model. We fit this model to a capture–recapture data set collected on the little penguin Eudyptula Minor in south-eastern Australia over a 25 year period using Jolly–Seber type estimators and nonparametric P-spline techniques. The time-varying coefficient model identified strong changes in the seasonal pattern across the years which we further examined using functional data analysis techniques. To evaluate the methodology we also conducted several simulation studies that incorporate seasonal variation.
Christopher P. Burridge - One of the best experts on this subject based on the ideXlab platform.
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Range-wide phylogeography of the little penguin (Eudyptula Minor): evidence of long-distance dispersal
The Auk, 2009Co-Authors: Amanda J. Peucker, Peter Dann, Christopher P. BurridgeAbstract:ABSTRACT. The Little Penguin (Eudyptula Minor), a colonial-nesting seabird that is widespread in New Zealand and southern Australia, has high dispersal potential but exhibits regional variation in morphology, coloration, and breeding phenology. We present a distribution-wide survey of mitochondrial DNA variation in the Little Penguin to document phylogeographic relationships and genetic structuring and to test for concordance with intraspecific taxonomy. Phylogeographic structuring was absent among Australian colonies (27 localities, 94 individuals), but the distribution of haplotypes among colonies was significantly nonrandom (φST = 0.110, P < 0.01). The Australian individuals exhibited close phylogenetic relationships with a subset of New Zealand birds (4 localities, 22 individuals), whereas the remaining New Zealand birds (20 localities, 106 individuals) were phylogenetically distinct, with ≥7% sequence divergence, and exhibited greater levels of genetic variation and geographic structuring (φST = 0.77...
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contrasting genetic structuring between colonies of the world s smallest penguin Eudyptula Minor aves spheniscidae
Conservation Genetics, 2008Co-Authors: Rebecca L. Overeem, Peter Dann, Amanda J. Peucker, Christopher P. Burridge, Christopher M. AustinAbstract:The Little Penguin, Eudyptula Minor, is a seabird that nests in colonies throughout New Zealand and southern Australia. Individuals from different colonies in southeast Australia differ significantly in morphology and ecology, suggesting that some genetic structuring may exist among colonies. In contrast, the marking of individuals with flipper bands has revealed some, albeit infrequent, movement between colonies. To determine the extent of genetic structuring, we tested the null hypothesis of substantial gene flow within southeast Australia by examining patterns of genetic variation across seven colonies separated by up to 1,500 km. Phylogeographic structuring was absent for mitochondrial control region sequences (2–3 individuals per colony). Microsatellite allele frequencies at five loci and mitochondrial haplotype frequencies (50 individuals per colony) were also homogenous among the majority of colonies sampled, although two colonies at the western periphery of the sampling range were distinct from those to the east. The genetic homogeneity among the majority of colonies can be explained by low but consistent contemporary gene flow among them, or a recent founder event in Bass Strait following the last marine transgression. The genetic break towards the western end of the sampling distribution appears best explained by differences in sea surface temperature and, consequentially breeding phenology, the latter hindering genetically effective migration.
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Contrasting genetic structuring between colonies of the World’s smallest penguin, Eudyptula Minor (Aves: Spheniscidae)
Conservation Genetics, 2007Co-Authors: Rebecca L. Overeem, Peter Dann, Amanda J. Peucker, Christopher M. Austin, Christopher P. BurridgeAbstract:The Little Penguin, Eudyptula Minor, is a seabird that nests in colonies throughout New Zealand and southern Australia. Individuals from different colonies in southeast Australia differ significantly in morphology and ecology, suggesting that some genetic structuring may exist among colonies. In contrast, the marking of individuals with flipper bands has revealed some, albeit infrequent, movement between colonies. To determine the extent of genetic structuring, we tested the null hypothesis of substantial gene flow within southeast Australia by examining patterns of genetic variation across seven colonies separated by up to 1,500 km. Phylogeographic structuring was absent for mitochondrial control region sequences (2–3 individuals per colony). Microsatellite allele frequencies at five loci and mitochondrial haplotype frequencies (50 individuals per colony) were also homogenous among the majority of colonies sampled, although two colonies at the western periphery of the sampling range were distinct from those to the east. The genetic homogeneity among the majority of colonies can be explained by low but consistent contemporary gene flow among them, or a recent founder event in Bass Strait following the last marine transgression. The genetic break towards the western end of the sampling distribution appears best explained by differences in sea surface temperature and, consequentially breeding phenology, the latter hindering genetically effective migration.
Christopher M. Austin - One of the best experts on this subject based on the ideXlab platform.
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contrasting genetic structuring between colonies of the world s smallest penguin Eudyptula Minor aves spheniscidae
Conservation Genetics, 2008Co-Authors: Rebecca L. Overeem, Peter Dann, Amanda J. Peucker, Christopher P. Burridge, Christopher M. AustinAbstract:The Little Penguin, Eudyptula Minor, is a seabird that nests in colonies throughout New Zealand and southern Australia. Individuals from different colonies in southeast Australia differ significantly in morphology and ecology, suggesting that some genetic structuring may exist among colonies. In contrast, the marking of individuals with flipper bands has revealed some, albeit infrequent, movement between colonies. To determine the extent of genetic structuring, we tested the null hypothesis of substantial gene flow within southeast Australia by examining patterns of genetic variation across seven colonies separated by up to 1,500 km. Phylogeographic structuring was absent for mitochondrial control region sequences (2–3 individuals per colony). Microsatellite allele frequencies at five loci and mitochondrial haplotype frequencies (50 individuals per colony) were also homogenous among the majority of colonies sampled, although two colonies at the western periphery of the sampling range were distinct from those to the east. The genetic homogeneity among the majority of colonies can be explained by low but consistent contemporary gene flow among them, or a recent founder event in Bass Strait following the last marine transgression. The genetic break towards the western end of the sampling distribution appears best explained by differences in sea surface temperature and, consequentially breeding phenology, the latter hindering genetically effective migration.
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Contrasting genetic structuring between colonies of the World’s smallest penguin, Eudyptula Minor (Aves: Spheniscidae)
Conservation Genetics, 2007Co-Authors: Rebecca L. Overeem, Peter Dann, Amanda J. Peucker, Christopher M. Austin, Christopher P. BurridgeAbstract:The Little Penguin, Eudyptula Minor, is a seabird that nests in colonies throughout New Zealand and southern Australia. Individuals from different colonies in southeast Australia differ significantly in morphology and ecology, suggesting that some genetic structuring may exist among colonies. In contrast, the marking of individuals with flipper bands has revealed some, albeit infrequent, movement between colonies. To determine the extent of genetic structuring, we tested the null hypothesis of substantial gene flow within southeast Australia by examining patterns of genetic variation across seven colonies separated by up to 1,500 km. Phylogeographic structuring was absent for mitochondrial control region sequences (2–3 individuals per colony). Microsatellite allele frequencies at five loci and mitochondrial haplotype frequencies (50 individuals per colony) were also homogenous among the majority of colonies sampled, although two colonies at the western periphery of the sampling range were distinct from those to the east. The genetic homogeneity among the majority of colonies can be explained by low but consistent contemporary gene flow among them, or a recent founder event in Bass Strait following the last marine transgression. The genetic break towards the western end of the sampling distribution appears best explained by differences in sea surface temperature and, consequentially breeding phenology, the latter hindering genetically effective migration.
Rebecca L. Overeem - One of the best experts on this subject based on the ideXlab platform.
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contrasting genetic structuring between colonies of the world s smallest penguin Eudyptula Minor aves spheniscidae
Conservation Genetics, 2008Co-Authors: Rebecca L. Overeem, Peter Dann, Amanda J. Peucker, Christopher P. Burridge, Christopher M. AustinAbstract:The Little Penguin, Eudyptula Minor, is a seabird that nests in colonies throughout New Zealand and southern Australia. Individuals from different colonies in southeast Australia differ significantly in morphology and ecology, suggesting that some genetic structuring may exist among colonies. In contrast, the marking of individuals with flipper bands has revealed some, albeit infrequent, movement between colonies. To determine the extent of genetic structuring, we tested the null hypothesis of substantial gene flow within southeast Australia by examining patterns of genetic variation across seven colonies separated by up to 1,500 km. Phylogeographic structuring was absent for mitochondrial control region sequences (2–3 individuals per colony). Microsatellite allele frequencies at five loci and mitochondrial haplotype frequencies (50 individuals per colony) were also homogenous among the majority of colonies sampled, although two colonies at the western periphery of the sampling range were distinct from those to the east. The genetic homogeneity among the majority of colonies can be explained by low but consistent contemporary gene flow among them, or a recent founder event in Bass Strait following the last marine transgression. The genetic break towards the western end of the sampling distribution appears best explained by differences in sea surface temperature and, consequentially breeding phenology, the latter hindering genetically effective migration.
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Contrasting genetic structuring between colonies of the World’s smallest penguin, Eudyptula Minor (Aves: Spheniscidae)
Conservation Genetics, 2007Co-Authors: Rebecca L. Overeem, Peter Dann, Amanda J. Peucker, Christopher M. Austin, Christopher P. BurridgeAbstract:The Little Penguin, Eudyptula Minor, is a seabird that nests in colonies throughout New Zealand and southern Australia. Individuals from different colonies in southeast Australia differ significantly in morphology and ecology, suggesting that some genetic structuring may exist among colonies. In contrast, the marking of individuals with flipper bands has revealed some, albeit infrequent, movement between colonies. To determine the extent of genetic structuring, we tested the null hypothesis of substantial gene flow within southeast Australia by examining patterns of genetic variation across seven colonies separated by up to 1,500 km. Phylogeographic structuring was absent for mitochondrial control region sequences (2–3 individuals per colony). Microsatellite allele frequencies at five loci and mitochondrial haplotype frequencies (50 individuals per colony) were also homogenous among the majority of colonies sampled, although two colonies at the western periphery of the sampling range were distinct from those to the east. The genetic homogeneity among the majority of colonies can be explained by low but consistent contemporary gene flow among them, or a recent founder event in Bass Strait following the last marine transgression. The genetic break towards the western end of the sampling distribution appears best explained by differences in sea surface temperature and, consequentially breeding phenology, the latter hindering genetically effective migration.
Amanda J. Peucker - One of the best experts on this subject based on the ideXlab platform.
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Range-wide phylogeography of the little penguin (Eudyptula Minor): evidence of long-distance dispersal
The Auk, 2009Co-Authors: Amanda J. Peucker, Peter Dann, Christopher P. BurridgeAbstract:ABSTRACT. The Little Penguin (Eudyptula Minor), a colonial-nesting seabird that is widespread in New Zealand and southern Australia, has high dispersal potential but exhibits regional variation in morphology, coloration, and breeding phenology. We present a distribution-wide survey of mitochondrial DNA variation in the Little Penguin to document phylogeographic relationships and genetic structuring and to test for concordance with intraspecific taxonomy. Phylogeographic structuring was absent among Australian colonies (27 localities, 94 individuals), but the distribution of haplotypes among colonies was significantly nonrandom (φST = 0.110, P < 0.01). The Australian individuals exhibited close phylogenetic relationships with a subset of New Zealand birds (4 localities, 22 individuals), whereas the remaining New Zealand birds (20 localities, 106 individuals) were phylogenetically distinct, with ≥7% sequence divergence, and exhibited greater levels of genetic variation and geographic structuring (φST = 0.77...
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contrasting genetic structuring between colonies of the world s smallest penguin Eudyptula Minor aves spheniscidae
Conservation Genetics, 2008Co-Authors: Rebecca L. Overeem, Peter Dann, Amanda J. Peucker, Christopher P. Burridge, Christopher M. AustinAbstract:The Little Penguin, Eudyptula Minor, is a seabird that nests in colonies throughout New Zealand and southern Australia. Individuals from different colonies in southeast Australia differ significantly in morphology and ecology, suggesting that some genetic structuring may exist among colonies. In contrast, the marking of individuals with flipper bands has revealed some, albeit infrequent, movement between colonies. To determine the extent of genetic structuring, we tested the null hypothesis of substantial gene flow within southeast Australia by examining patterns of genetic variation across seven colonies separated by up to 1,500 km. Phylogeographic structuring was absent for mitochondrial control region sequences (2–3 individuals per colony). Microsatellite allele frequencies at five loci and mitochondrial haplotype frequencies (50 individuals per colony) were also homogenous among the majority of colonies sampled, although two colonies at the western periphery of the sampling range were distinct from those to the east. The genetic homogeneity among the majority of colonies can be explained by low but consistent contemporary gene flow among them, or a recent founder event in Bass Strait following the last marine transgression. The genetic break towards the western end of the sampling distribution appears best explained by differences in sea surface temperature and, consequentially breeding phenology, the latter hindering genetically effective migration.
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Contrasting genetic structuring between colonies of the World’s smallest penguin, Eudyptula Minor (Aves: Spheniscidae)
Conservation Genetics, 2007Co-Authors: Rebecca L. Overeem, Peter Dann, Amanda J. Peucker, Christopher M. Austin, Christopher P. BurridgeAbstract:The Little Penguin, Eudyptula Minor, is a seabird that nests in colonies throughout New Zealand and southern Australia. Individuals from different colonies in southeast Australia differ significantly in morphology and ecology, suggesting that some genetic structuring may exist among colonies. In contrast, the marking of individuals with flipper bands has revealed some, albeit infrequent, movement between colonies. To determine the extent of genetic structuring, we tested the null hypothesis of substantial gene flow within southeast Australia by examining patterns of genetic variation across seven colonies separated by up to 1,500 km. Phylogeographic structuring was absent for mitochondrial control region sequences (2–3 individuals per colony). Microsatellite allele frequencies at five loci and mitochondrial haplotype frequencies (50 individuals per colony) were also homogenous among the majority of colonies sampled, although two colonies at the western periphery of the sampling range were distinct from those to the east. The genetic homogeneity among the majority of colonies can be explained by low but consistent contemporary gene flow among them, or a recent founder event in Bass Strait following the last marine transgression. The genetic break towards the western end of the sampling distribution appears best explained by differences in sea surface temperature and, consequentially breeding phenology, the latter hindering genetically effective migration.