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Emu - Austral Ornithology Volume 115, Issue 1, 2015 Summaries Editorial: A quantum leap in avian biology Leo Joseph and Katherine L. Buchanan Emu – Austral Ornithology 115(1), 1–5 http://www.publish.csiro.au/paper/MUv115n1_ED.htm The frequency of ingested plastic debris and its effects on body condition of Short-tailed Shearwater (Puffinus tenuirostris) pre-fledging chicks in Tasmania, Australia Hannah R. Cousin , Heidi J. Auman , Rachael Alderman and Patti Virtue Emu – Austral Ornithology 115(1), 6–11 http://www.publish.csiro.au/paper/MU13086.htm Observations of wildlife deaths and injuries from entanglement in or ingestion of plastic debris are increasing around the world. Seabirds in particular are facing greater exposure to this threat as levels of marine plastic pollution increases. Short-tailed Shearwaters (Puffinus tenuirostris) are one seabird species that could be exposed to this increasing threat, owing to their foraging range spanning both hemispheres and several oceans. With their abundance and circum-Pacific migratory range, birds that feed by surface-seizing, such as Short-tailed Shearwaters, can be considered potential indicators of plastic accumulation in the ocean, an issue of increasing international concern. We recorded a total of 1032 pieces of plastic (weighing 25.3 g) from 171 dead Short-tailed Shearwater chicks from Clifton Beach, Tasmania; there was an average 148.1 mg and 6.03 pieces of plastic per bird. From this study we were able to conclude that the presence and amount of plastic, transferred from parents during feeding, had no significant effect on growth and body morphology of chicks. However, it is a significant concern, particularly in the greater context of marine pollution on a global scale, that 96% of these fledgling chicks from a relatively remote area are experiencing plastic marine debris ingestion. Avian responses to varying intensity of cattle production in Spartina densiflora saltmarshes of south-eastern South America Daniel Augusto Cardoni , Juan Pablo Isacch and Oscar Iribarne Emu – Austral Ornithology 115(1), 12–19 http://www.publish.csiro.au/paper/MU13028.htm Saltmarshes occur along the coasts of all major continents except Antarctica. These ecosystems are dominated by a few dominant species of salt-tolerant grasses, such as species of Spartina. Saltmarshes in South America, as elsewhere, have been significantly modified by anthropogenic activities, particularly production of livestock. We examined the effect of the intensity of cattle production on the structure of Spartina densiflora saltmarsh vegetation, and how these changes affected the richness and composition of their bird populations and the abundance of nests. The study assessed three levels of intensity of cattle production and burning: high, low and none. Cattle production changed the structure of saltmarsh vegetation, and modified the richness, abundance and composition of the avian community and the abundance of nests. Saltmarshes with low intensity or no cattle production were inhabited by specialised and threatened birds of tall grasslands. Conversely, saltmarshes with a high intensity of cattle production were dominated by short grasses bird species. That avian species diversity does not differ in areas of saltmarsh subject to either low levels of, or no, production intensity has important implications for management of saltmarsh–grassland communities for conservation of avian diversity. Variation in productivity of Grey-faced Petrels (Pterodroma gouldi) with local burrow density and breeding island Christopher J. Jones , Philip O’B. Lyver , Catriona J. Macleod , Amy L. Whitehead and Guy J. Forrester Emu – Austral Ornithology 115(1), 20–28 http://www.publish.csiro.au/paper/MU14018.htm For long-lived birds, estimates of how successfully they breed can be effective indicators of environmental change or responses to management. We used fibre-optic cameras to survey Greyfaced Petrel nesting burrows on four islands off the north-eastern coast of New Zealand for up to four breeding seasons and followed the fates of 1371 eggs. Daily nest-survival rates declined with increasing local burrow density across all islands. We found variable overall breeding success rates of 11 28% across the four sites. This variation in productivity between our study colonies may be linked to differences in the restoration histories of the islands or the presence of other breeding seabirds at some sites. These differences suggest that data from one location should be used cautiously when guiding management of the same species elsewhere. Study of seed dispersal by Emu (Dromaius novaehollandiae) in the Jarrah (Eucalyptus marginata) forests of south-western Australia through satellite telemetry Andrew P. Nield , Neal J. Enright and Philip G. Ladd Emu – Austral Ornithology 115(1), 29–34 http://www.publish.csiro.au/paper/MU13113.htm The use of advanced technology, such as the global positioning system (GPS), allows scientists to better-understand the movement and behaviours of organisms in different environments. We used GPS devices to track the movement of Emus in the Jarrah forests of south-western Australia. As a large bird that consumes the seeds of many forest species, the Emu plays an important role in seed dispersal and plant regeneration. We found that the GPS-tagged Emus were capable of travelling many kilometres during relatively short periods (weeks), avoiding steep slopes and preferring to remain within the forested areas. These extensive distances covered indicate that the Emu moves many seeds over long distances throughout the Jarrah forests. From a methodological perspective, half of our GPS devices detached before 30 days of tracking data could be recorded. Further studies of Emu movement within forested areas needs to consider device refinement to enable the collection of additional data. Evolutionary history of birds across southern Australia: structure, history and taxonomic implications of mitochondrial DNA diversity in an ecologically diverse suite of species Gaynor Dolman and Leo Joseph Emu – Austral Ornithology 115(1), 35–48 http://www.publish.csiro.au/paper/MU14047.htm The use of DNA sequences to read the footprint of evolution has grown explosively in the last 25 years. In this paper, DNA sequences are used to understand how the present-day genetic diversity of bird species in southern Australia has been shaped by both environmental forces and the ecology of the birds themselves. While affirming expectations that species of wetter habitats were isolated between eastern and western Australia much earlier than species of drier habitats, we also see how species that move widely in search of food have less genetic structure than more sedentary species. In addition, this paper also argues the need for changes to how we classify some birds. We are suggesting that some birds considered as one species until now need to be recognised as two species. In other cases, we can pinpoint where more work is needed before such a decision can be made. The importance of winter-flowering Aloe ferox for specialist and generalist nectar-feeding birds Timothy R. Kuiper , Diane L. Smith , Milena H. L. Wolmarans , Sara S. Jones , Ross W. Forbes , Patrick E. Hulley and Adrian J. F. K. Craig Emu – Austral Ornithology 115(1), 49–57 http://www.publish.csiro.au/paper/MU14054.htm In southern Africa, many Aloe species flower in the austral winter, when nectar sources are scarce. We have followed the changes in the bird population at a stand of Aloe ferox in the Eastern Cape, South Africa, for five seasons. When the aloes are in flower from June to August, there is a marked influx of both specialist nectar feeders (sunbirds) and a range of other bird species that feed opportunistically on nectar. At other times of year these birds are seldom seen at the site. Using standard point-counts to record both the diversity and numbers of birds, we have found that Malachite Sunbirds and three different weavers (Ploceus spp.) are the most numerous flower visitors, although 17 other species of bird have also been seen feeding on nectar at this site. For Aloe ferox, the shortbilled weavers and other opportunistic nectar feeders are the important pollinators, whereas the longbilled sunbirds carry very little pollen on their feathers. Molecular analysis suggests the occurrence of Shy Albatross in the south-western Atlantic Ocean and its by-catch in longline fishing Sebastián Jiménez , Alejandro Marquez , Martin Abreu , Rodrigo Forselledo , Alfredo Pereira and Andrés Domingo Emu – Austral Ornithology 115(1), 58–62 http://www.publish.csiro.au/paper/MU13105.htm Albatrosses are killed or injured through by-catch in longline fisheries and by collisions with warp cables in trawl fisheries. Here we document the species of a sample of 29 shy-type albatrosses killed as fisheries by-catch to confirm the observation that White-capped Albatrosses (Thalassarche steadi) are the dominant shy-type albatross in the south-western Atlantic Ocean and exposed to the pelagic longline fishery there. Using genetic analyses, we found that 28 specimens were White-capped Albatrosses. There is no doubt that the White-capped Albatross, which is a regular visitor to Uruguayan waters, is the predominant shy-type albatross in the south-western Atlantic. However, these analyses also suggested that the remaining bird was a Shy Albatross (T. cauta). This result indicates the possibility that a small proportion of shy-type albatrosses in this region could be Shy Albatross but further analysis is required to confirm this. Variation in innate immune function during incubation, chick-rearing and moult in Little Penguins (Eudyptula minor) Jessica K. Evans , Peter Dann and Theresa Frankel Emu – Austral Ornithology 115(1), 63–71 http://www.publish.csiro.au/paper/MU13077.htm A functional and robust immune system is essential for maintaining the ability to combat diseases. Stresses caused by changed environmental conditions or food availability, as well as those originating in birds through their natural annual cycles and habitats, can seriously reduce immune function. We assessed the functionality of the immune system of Little Penguins during their main periods of stress – moulting, egg laying and chick-rearing – using blood samples. The test showed that during late chick-rearing, when food requirements are at their highest, and during egg incubation, when Little penguins do not require as much food and are exposed to greater levels of environmental contamination, the bacteria E. coli were not destroyed by blood immune factors. Results such as these can show when susceptibility to diseases is likely to pose the greatest risk to penguins. Nest-spacing, not human presence, influences the breeding of Chimango Caracaras (Milvago chimango) in a peri-urban reserve Claudina Solaro and José Hernán Sarasola Emu – Austral Ornithology 115(1), 72–75 http://www.publish.csiro.au/paper/MU14038.htm Urban development has heavily transformed many natural environments around the world and some bird species seem to be tolerant to these changes. The chimango caracara (Milvago chimango) is one of the most common and abundant birds of prey in southern South America usually found in towns and cities. We studied the breeding biology of chimango caracaras in a peri-urban zone in central Argentina to evaluate the spatial arrangement of nests and the reproductive response of this species to human disturbances. We found that chimango caracara nested in a dense colony and that a relatively low reproductive output was exhibited by this species. However, such low reproductive success was not explained by human presence in our study area. Rather, the proximity of co-specific nests (i.e. the relatively small distance between neighbouring nests) had greater negative effects on individual breeding performance than human presence. Our results show that chimango caracaras are able to breed in highly human-modified environments. However, several aspects of chimango caracaras’ behaviour and ecology in urban landscapes may be determined by anthropogenic pressures that ultimately drive their fitness in these modified habitats. Biparental nest-attendance in Chilean Swallows (Tachycineta meyeni) breeding in Ushuaia, Argentina Emilie A. Ospina , Caren B. Cooper , Marcela Liljesthröm , Daniel R. Ardia and David W. Winkler Emu – Austral Ornithology 115(1), 76–79 http://www.publish.csiro.au/paper/MU14036.htm Avian embryos require consistent high temperatures to develop properly. Providing these high temperatures through incubation is an energetically demanding activity. Thus adult birds balance their energy needs with the thermal needs of the eggs. In a population of Chilean swallows nesting in a cold region, the southern tip of Tierra del Fuego, Ushuaia, Argentina, we video documented the incubation behaviour of male and female parents. We installed small cameras and temperature probes into the nests of three pairs of swallows and discovered that in each, the male bird assisted to some degree in the incubation of the eggs within the nest. Our interpretation of the video and temperature data is that one bird (the female) actively provides heat to the eggs, raising their temperature well above ambient, while a second bird (the male) attends the eggs to decrease the rate at which they cool during the minutes that the female is away from the nest to forage. This study is the first to document male incubation behaviour in the Chilean swallow. Relationship between pest birds and landscape elements in the Pampas of central Argentina Mariano Codesido , Emmanuel Zufiaurre and David Bilenca Emu – Austral Ornithology 115(1), 80–84 http://www.publish.csiro.au/paper/MU13110.htm In agroecosystems, some bird species may become abundant and cause problems as agricultural pests. But why is that so? What are the elements in the landscape that make such species abundant? It has been postulated that a mosaic landscape of crops and wooded patches are associated with an increase in the numbers of pest birds in agricultural landscapes. We chose to investigate this relationship in the Pampas of Argentina, an extensive and formerly treeless grassland region that has become one of the largest agricultural regions of the world. Recently, woodlands of exotic tree species have self-established along riparian zones and roadsides, and patches of trees have also been planted near rural buildings and cattlelots. We estimated the abundance of four species of birds that are considered pest species in this region: Eared Dove, Monk Parakeet, Picazuro Pigeon and Spotwinged Pigeon. We found that these pests species in the study area respond more to the presence of woodlots rather than to the presence of croplands in the landscape. These results have practical implications, suggesting that management of woodlots of exotic trees may providean effective method of control of pest-bird species in the Pampas of Argentina. Book Reviews AN EYE FOR NATURE: THE LIFE AND ART OF WILLIAM T. COOPER By Penny Olsen BIRDS OF NEW GUINEA: SECOND EDITION By Thane K. Pratt and Bruce M. Beehler http://www.publish.csiro.au/paper/MUv115n1_BR.htm Emu - Austral Ornithology is published quarterly by CSIRO Publishing, and is available to BirdLife Australia members at a discounted subscription rate. Click here to join.