Pre-release Articles

Download	1. History of the East Point monsoon forest.
Authors	onald C. Franklin, Roger Matthews and Michael J. Lawes
Abstract	The 135-hectare East Point Reserve, much of which forms a peninsula projecting into the Beagle Gulf from the city of Darwin, contains a significant remnant of coastal monsoon forest and is abutted in part by mangroves. Historical evidence suggests that monsoon forest once occupied almost all the peninsula, whereas the remnant now occupies 20% of it. Almost half the forest loss occurred prior to 1945 associated with use of the peninsula by the Australian military. The other half was cleared for a golf course and other purposes that we could not identify between 1945 and 1963, mostly between 1955 and 1963. Cyclone Tracy inflicted severe damage to the forest in 1974 but most tree species resprouted. The mangrove stand on the north side of the base of the peninsula has retreated coastward, thickened and extended westward, whilst a smaller stand on the southern side was cleared and has almost disappeared. Since taking over management of the area in 1984, Darwin City Council has revegetated about 20% of the peninsula. Agile Wallabies Macropus agilis present in the Reserve proliferated during the 1980s, damaging remnant forest and replantings, but the population returned to much lower densities during the 1990s following closure of most watering points. Significant on-going management issues for the forest include the cost of further revegetation, and weed control. Invasion of remnant forest by Poinciana Delonix regia, an attractive non-native tree, may prove to be a controversial management issue in the future.
Tags

---

Download	2. Distribution and conservation status of the Giant Sweet Potato, a rare Aboriginal food plant from Central Australia
Authors	Beth Crase, Angus Duguid, Raymond Nelson Pengart, Paddy Willis Jakamarra, Laurie Price Angal, Margaret Scobie Pengart and Aggie Woods Kemarr
Abstract	The Giant Sweet Potato, Ipomoea polpha subsp. latzii R.W.Johnson (Convolvulaceae), or “Antjulkinah”, is a rare plant endemic to central Australia, and features prominently in the mythology of the Traditional Owners of the area, the Anmatjerre people. The taxon is known from three sub-populations and has a highly restricted geographic distribution. Our study of the distribution, density and population size of Ipomoea polpha subsp. latzii incorporated traditional ecological knowledge, and led to the identification of an additional extensive sub-population. The distance-transect method was used to calculate estimates of population size and density for the Giant Sweet Potato, and is one of the only published examples of the application of this method to a plant species. We estimate the area of occupancy of the taxon to be at least 26.7 km2, significantly greater than the population estimate reported by a survey in 1987. Our data support listing the species as Vulnerable under IUCN (2008) criterion D2.
Tags

---

Download	3. Fine-scale patchiness of burns in a mesic eucalypt savanna differs with fire season and Sorghum abundance
Authors	Patricia A. Werner
Abstract	Canopy tree populations in the eucalypt savannas of northern Australia consistently show bottlenecks in the transition of young trees to the canopy layer. This is most likely due to frequent fires, where young trees are caught in a ―fire trap‖, suffer topkill and regenerate from underground tissues year after year. Little is known of fire behaviour at the spatial scale of individual juvenile trees. This paper presents field measurements of small-scale, 10 cm (microsite), burn patterns and patch sizes following set fires in the early dry season, late dry season, and wet season. Fire treatments were repeated in plots dominated by a native annual grass (Sorghum) and in others with little or none of this grass. Both late dry season and wet season fires left few or no microsites unburnt, regardless of understorey type. With early dry season fire, however, understorey type made a difference: 47% of the microsites were left unburnt in plots with little or no Sorghum compared to only 5% in Sorghum-dominated plots. Further, the early dry season fire pattern was very patchy, resulting in both large and small areas of burnt vegetation. In Sorghum-dominated plots, more than half the patches were ≥ 10 m in size and only a third were < 3 m in size, whereas in plots with little or no Sorghum, 99% of burnt patches were < 10 m in size, and 41% were < 0.5 m in size. Thus, only a regime of early dry season fire with little or no Sorghum in the understorey creates potential ―windows of escape‖ for juvenile trees. The study has implications for management of savanna trees by fire.
Tags

---

Download	4. Birdlife of Mickett Creek: factors influencing frequency of occurrence and detection
Authors	Stephen J. Reynolds
Abstract	Over a five-year period 82 bird species were recorded during diurnal visits to the Mickett Creek area near Darwin. Frequently recorded species were generally those that were resident (hence present all year round), were moderately to highly abundant, and vocalised regularly. Species with loud or highly penetrating calls and vocally active species may have been recorded more often than other birds of similar abundance. Infrequently recorded species included seasonal visitors, particularly dry season migrants and birds associated with seasonal wetlands, and discreet species that are presumably resident but are rarely detected because of secretive habits and vocalisation characteristics. Nocturnal species were infrequently flushed during the day, but are known from the area from nocturnal surveys. Habitat types, seasonal distribution of water, food resources, and movement patterns of birds affect species composition at a local scale. It is concluded that numerous surveys over many years are required to obtain a comprehensive avifaunal species inventory for bushland sites in monsoonal northern Australia.
Tags

---

Download	5. Home range and movement patterns of an Estuarine Crocodile Crocodylus porosus: a satellite tracking pilot study
Authors	Bindi Thomas, John D. Holland and Edward O. Minot
Abstract	The number of Estuarine Crocodiles Crocodylus porosus in the Northern Territory, Australia is increasing. This has led to an increase in interaction with humans and livestock. Whilst there have been a number of studies on the distribution and movement of crocodiles in Australia, little has been recorded detailing movement patterns, and less evaluating the technical effectiveness of employing satellite tracking technology on this species. We attached an Argos satellite transmitter to a 4.2 m male Estuarine Crocodile captured in the Adelaide River, approximately 100 km east of Darwin, Northern Territory, Australia. During the six month study period (July to December 2005), the crocodile showed definite signs of home range fidelity, staying within a Minimum Convex Polygon of 63 km² and a 95% kernel area of 8 km². The average daily movement was 5.9 km day-1 with increased movement during the month of December. A high percentage of useable locations (65%) were received from the Platform Terminal Transmitter, with an increased number of location readings occurring between 2000 and 0700 hours. Given the aggressiveness of this species and the hostile environments in which they live, the Argos system is a useful method for tracking their movement. The results of this study have provided preliminary information improving our understanding of the home range and behaviour of a large male crocodile.
Tags

---

Download	6. An extralimital record of Grey-headed Honeyeater Lichenostomus keartlandi from Darwin, Northern Territory
Authors	Peter M. Kyne and Micha V. Jackson
Abstract	The Grey-headed Honeyeater Lichenostomus keartlandi is considered a bird of inland vegetation communities of arid and semi-arid Australia (Higgins et al. 2001). It is a resident or locally nomadic honeyeater endemic to northern inland Australia. Within the Northern Territory, its normal range is south of near Top Springs (16°32′37″S, 131°47′52″E) in the west and Mount Roper (14°48′59″S, 135°03′02″E) in the east (Storr 1977; Higgins et al. 2001). The species occurs in a variety of habitats, but primarily in low open eucalypt (including mallee) and mulga woodlands in sandstone ranges, rocky gorges, tablelands and plains; its habitat is dominated by low, stunted vegetation, often with spinifex ground cover (Higgins et al. 2001). It also occurs in inland riparian vegetation and less commonly in Mitchell grass dominated grasslands (Higgins et al. 2001). Between approximately 1100 and 1130 hours on 21 February 2010, an adult Grey-headed Honeyeater was observed and photographed at East Point, Darwin, Northern Territory (12°24′23″S, 130°49′00″E) (Figure 1). This is c. 270 km (2°25′) north of its previously documented range in northern Australia.
Tags

---

Download	7.
Authors	Alan N. Andersen
Abstract	A previous report in the Northern Territory Naturalist (Andersen et al. 2008) described a noteworthy interaction between fallen trees, fire and Annual Sorghum (Sarga sp.) following a freak tornado in March 2007 that deforested approximately 3 km2 of savanna woodland in Kakadu National Park. During the following wet season there were numerous gaps in Annual Sorghum cover associated with the burning of fallen trees during the 2007 dry season. Some of these gaps were linear and associated with burnt tree trunks, whereas others were far more extensive and associated with the burning of canopy branches. The sorghum gaps were attributed to local mortality of the seed bank due to lethal subsurface soil temperatures caused by long fire residence times, possibly associated with smouldering combustion. Many of the sorghum gaps were almost completely bare, indicating that other herbaceous species were similarly affected by high fire residence times.
Tags

---

Download	8. Breaking free: Gould’s Bronze-Cuckoo nestlings can forge a second exit to fledge from domed host nests
Authors	Emma J. Rosenfeld, Golo Maurer and Naomi E. Langmore
Abstract	Gould’s Bronze-Cuckoos Chalcites minutillus russatus frequently parasitize the domed nests of Large-billed Gerygones Gerygone magnirostris. Here we report three instances of cuckoo chicks creating a characteristic second exit in the narrow hooded entrance of the nest upon fledging. This behaviour may help cuckoo chicks to fledge securely from domed nests.
Tags

---

Download	9. Exploring the adequacy of representation of butterfly species’ distributions in a more accessible portion of northern Australia
Authors	Kelvyn L Dunn and Donald C. Franklin
Abstract	Results of a 13-day field survey of butterflies in the Darwin – Katherine – Kakadu area in 2008 are compared with existing synoptic maps and a private national database of butterfly records. Ten records of four species are beyond distributions previously mapped for them. The most substantial extensions (> 200 km) are for a species (Cephrenes augiades) that may be expanding its range and another (Nacaduba biocellata) that may be subject to large-scale seasonal irruptions. The Darwin – Katherine – Kakadu area has been moderately surveyed by Australian standards but has only one record of each species per 3,700 km2. Whilst it is likely that national synoptic maps of species’ distributions represent the ranges of most species reasonably accurately, much remains to be learnt about butterfly distributions in the region.
Tags

---

Download	10. Notes on species of Hyptis Jacq. (Lamiaceae) naturalised in the Northern Territory, Australia
Authors	Philip Short and Kathy De La Rue
Abstract	Weeds are present in all but the most pristine of environments. For anyone wishing to know when species were introduced to a region, and how quickly they have spread, the best records frequently come from herbarium specimens. Indeed, specimens provide the best means of tracking the spread of a species because their identity can be checked. Providing the species in question is readily identifiable, written records, and sometimes verbal records, can also be used with confidence. We use herbarium specimen data and written records to document the time of introduction and establishment of all three species of Hyptis now recorded for the Northern Territory. We also comment on some of their weedy attributes and outline early attempts to eradicate H. suaveolens from Darwin.
Tags

---

Download	11. Book Review: The Top of the Top End: John Gilbert’s Manuscript Notes for John Gould on Vertebrates from Port Essington and Cobourg Peninsula (Northern Territory, Australia)
Authors	Philip Short
Abstract	This latest supplement of The Beagle is a marvellous publication for anyone interested in the history of the discovery of Australia’s flora and fauna. It is a meticulously researched, highly readable and beautifully illustrated work.
Tags

---