Topic
Anas castanea
About: Anas castanea is a research topic. Over the lifetime, 17 publications have been published within this topic receiving 188 citations.
Papers
TL;DR: The abundance and richness of seeds carried internally and externally did not differ among sympatric bird species and Sedentary waterfowl are likely to have an important role in replenishing propagules and connecting aquatic metacommunities over small distances.
Abstract: Summary
1. Dispersal of propagules by waterbirds is thought to be important for wetland plants because of the abundance of birds and their frequent movements among aquatic habitats. Differences in bird characteristics (size, movement, feeding ecology) were expected to lead to different outcomes for plant dispersal.
2. We investigated heterogeneity in plant dispersal by ducks (Anas superciliosa, Anas gracilis, Anas castanea). We calculated the probability of transport of viable seeds by germinating propagules retrieved from feathers and feet (epizoochory) and the contents of the oesophagus, gizzard and lower gut (endozoochory).
3. The abundance and richness of seeds carried internally and externally did not differ among sympatric bird species. We used estimates from the literature of movements of Anas species to approximate dispersal kernels for the transport of plant propagules.
4. Heterogeneity in the abundance and movement ecology of disperser species will result in differing patterns and degrees of connectivity for wetland plant metacommunities. Sedentary waterfowl are likely to have an important role in replenishing propagules and connecting aquatic metacommunities over small distances. Nomadic waterfowl may facilitate long-distance dispersal. We discuss the implications of differences between duck species in movement patterns for connectivity of aquatic plant metacommunities across landscapes.
38 citations
TL;DR: To estimate phylogenetic relationships of teals, three mitochondrial DNA genes were sequenced and unequivocally groups the Chestnut Teal with the Grey Teal, rather than with the New Zealand teals as has traditionally been held (Fleming 1953).
Abstract: The taxonomy of the Australasian teals has been particularly unstable. Australasian Grey Teal (Anas gracilis) and Chestnut Teal (A. castanea) are widely viewed as specifically distinct, but the taxonomy of the New Zealand teals remains unsettled. Because conservation status is affected by taxonomic rank, it is important to resolve the status of the rare subantarctic teals. To estimate phylogenetic relationships of teals, we sequenced three mitochondrial DNA genes (12S, and ATPase 6 and 8). The resultant phylogeny unequivocally groups the Chestnut Teal with the Grey Teal, rather than with the New Zealand teals as has traditionally been held (Fleming 1953). A greater level of sequence divergence occurred within the New Zealand teals than between the Grey and Chestnut teals. This diversity, together with morphological and behavioral differences, implies that the New Zealand teals should be accorded specific status as A. aucklandica, A. nesiotis, and A. chlorotis. Although it is most likely that the ...
35 citations
TL;DR: The type material of the nine species of fossil ducks described from Australia by C. W. De Vis was restudied and lectotypes designated for all species based on series, finding no valid extinct species were represented.
Abstract: The type material of the nine species of fossil ducks described from Australia by C. W. De Vis was restudied and lectotypes designated for all species based on series. No valid extinct species were represented. Nyroca robusta is a synonym of Anas superciliosa. Nyroca reclusa and Anas elapsa are synonyms of Aythya australis. Nyroca effodiata is a synonym of 'Leucosarcia proevisa' De Vis and is not a duck at all. Anus strenua, Anas gracilipes and Nettapus eyrensis are synonyms of Anas castanea, which species evidently had a wider range in the late Pleistocene than at present. Dendrocygna validipinnis and Biziura exhumata are synonyms of Biziura lobata, although the Plio-Pleistocene form may have been slightly smaller, in which case it would be known as Biziura lobata validipinnis.
18 citations
TL;DR: This is the first report of a H9N2 avian influenza virus in resident wild birds in Australia, and is a clear indication of spillover and likely reassortment of influenza viruses between migratory and resident birds, and an indication that any lineage could potentially be introduced in this way.
Abstract: The present study reports the genetic characterization of a low-pathogenicity H9N2 avian influenza virus, initially from a pool and subsequently from individual faecal samples collected from Chestnut teals (Anas castanea) in southeastern Australia. Phylogenetic analyses of six full gene segments and two partial gene segments obtained from next-generation sequencing showed that this avian influenza virus, A/Chestnut teal/Australia/CT08.18/12952/2018 (H9N2), was a typical, low-pathogenicity, Eurasian aquatic bird lineage H9N2 virus, albeit containing the North American lineage nucleoprotein (NP) gene segment detected previously in Australian wild birds. This is the first report of a H9N2 avian influenza virus in resident wild birds in Australia, and although not in itself a cause of concern, is a clear indication of spillover and likely reassortment of influenza viruses between migratory and resident birds, and an indication that any lineage could potentially be introduced in this way.
14 citations
1 Jan 1987
TL;DR: It is concluded that males are not accompanying broods primarily to maintain a pair-bond, but rather they are protecting the smaller ducklings especially prone to predation.
Abstract: Details of clutch sizes and subsequent productivity are presented for Chestnut Teal Anas castanea using artificial nest boxes. Survival of ducklings marked in the nests and subsequently trapped is discussed in relation to contemporary counts of broods. The role of both parents in brood care was investigated. Clutch sizes were affected by the disappearance of marked eggs and by the presence of eggs from previous clutches and other females. There was little evidence to show between season variations in clutch sizes but separation into early, mid, or late season clutches did show some differences. Relatively few tagged ducklings were found dead in boxes but mortality, particularly in the period immediately after leaving the boxes, was high. In general, broods of all ages were smaller when no parent was in attendance, and broods attended by both parents were larger than those accompanied by a single parent of either sex. Male Chestnut Teal attendance declined with increasing brood age. Males were observed to take active roles in brood protection and defense. It is concluded that males are not accompanying broods primarily to maintain a pair-bond, but rather they are protecting the smaller ducklings especially prone to predation.
13 citations
Related Topics (5)
Performance Metrics
| Year | Papers |
|---|---|
| 2020 | 1 |
| 2016 | 2 |
| 2011 | 1 |
| 2010 | 2 |
| 2009 | 1 |
| 2007 | 1 |