Dissertations / Theses on the topic 'Pond ecology – New South Wales'

The environmental history of Longneck Lagoon was reconstructed by analysing 15 sediment cores collected between 22 April, 1992 and 29 August, 1995. Longneck Lagoon is a shallow, man-modified lake situated in the north-western part of Sydney in New South Wales, Australia, in the Hawkesbury River floodplain. It has undergone a considerable change over recent years and at the end of the study was reported to have turbid water and no floating leaved plants or submerged aquatic plants. The hypothesis of this study was that vertical patterns in sediment characteristics can be related to biological, physical or chemical changes that have taken place within Longneck Lagoon and its catchment area. Assessment of inter-core variation within one area of the lagoon and between different areas was carried out and is highly recommended to others who may wish to conduct similar studies elsewhere. Restoration/regeneration of the previous diverse aquatic plant flora, associated with variable water depth in the pre-weir condition, would require the removal/modification of the weir, possibly reduction in the nutrient income to the lake, and, potentially, addressing mobilisation and internal cycling of accumulated nutrients which have accreted within the system.
Doctor of Philosophy (PhD)

This thesis explores issues relating to the application of physiological-process models (???process models???) of forest growth to mixed species, mixed age forests, in particular the coastal blackbutt forests of New South Wales. Using a dataset provided by State Forests of New South Wales (Carter 1994 unpubl.) a numeric description of the forest was developed and stand-level parameters of interest were derived, in particular the plot by plot stemwood volume growth from 1975 to 1999. The amounts of harvested volume, volume that died and volume that grew into the measurement population were identified separately, and several different means of accounting for volume change over time were investigated. A method for quantifying the impact of harvesting and other silvicultural practices on the growth of the forest was developed and programs were written to convert the stand-level summary of the harvest impact into a semi-random selection of trees that would be ???harvested??? from the database under the set of silvicultural assumptions (Dore et al. 1999). A number of process models were investigated and reviewed before selecting one particular model, SUSTAIN (Dewar 1997) for adaption to these forests. This model is a relatively simple process model with a small number of input parameters. The model was adapted so that it could be used to compare the SUSTAIN estimate of growth with the growth of an individual stand of trees in the Kendall Forest Management Area, between Wauchope and Taree on the mid-north coast of NSW. To improve the accuracy of the prediction of growth by SUSTAIN, a method of re-setting the state of the stand to the actual condition at the time of remeasurement was developed. In addition, the SUSTAIN model was extended to enable two separate levels of canopy to be described and grown separately. Ultimately the model was only partially successful in mirroring the growth predicted by the empirical data. Its partial success is attributed primarily to the difficulties associated with correctly determining the allocation parameters used by the model to assign net photosynthate to the roots, foliage and stemwood. The nature of the change in allocation parameters when the forest stand is disturbed by harvest or fire needs further investigation.

Thesis by publication.
Thesis (PhD)--Macquarie University (Division of Environmental & Life Sciences, Graduate School of the Environment), 2007.
Bibliography: p. 267-303.
General introduction -- Redescription of two species of wobbegongs (Chondrichthyes: Orectolobidae) with elevation of Orectolobus halei Whitley 1940 to species level -- Using recreational scuba-divers to survey the relative abundance and distribution of wobbegong sharks (Family: Orectolobidae) in New South Wales, Australia -- Observations of localised movements and residence time of wobbegong sharks (Orectolobus halei) at Fish Rock, New South Wales, Australia -- Length-frequency distribution, length-length, mass-mass and mass-length relationships of wobbegong sharks (Genus Orectolobus) commercially fished in New South Wales, Australia -- Quantitative diet assessment of wobbegong sharks (Genus Orectolobus) in New South Wales, Australia -- Reproductive synchrony of three sympatric species of wobbegong shark (Genus Orectolobus) in New South Wales, Australia -- Age and growth of wobbegong sharks (Genus Orectolobus) in New South Wales, Australia.
In New South Wales, Australia, wobbegong sharks (Orectolobidae) have been commercially targetted by the Ocean Trap and Line Fishery since 1991. A catch decrease of ca. 50% in a decade lead to concern over the sustainability of the fishery and to wobbegongs being listed as vulnerable in NSW under the World Conservation Union Red List assessment. The aim of this research was to investigate wobbegong biology and ecology in relation to its fishery to provide essential data and information for sustainable management of the woggegong fishery. Biological data was obtained from 904 wobbegongs collected from commercial fishing boats, using setlines and lobset pots and by scuba diving. previously two species of wobbegongs were known to occur in NSW: the spotted wobbegong (Orectolobus maculatus) and the ornate wobbegong (O. ornatus). This study discovered a new species (O. halei) described as a subspecies by Whitley (1940), but which had been syonymised with O> ornatus due to a lack of taxonomic investigation.
Mode of access: World Wide Web.
307 p. ill., some col., maps

The red fox occurs across a very broad range of habitats, and displays great behavioural flexibility under different environmental conditions. In Australia, mounting concern over the impacts of foxes on livestock and native fauna has highlighted a need for more information on fox ecology under Australian conditions as a fundamental step towards developing more strategic means of managing foxes. This study explores ranging behaviour, dispersal, use of dens, activity rhythms, population dynamics and diet in the absence of management in productive agricultural land in the central tablelands of New South Wales. The study was conducted from June 1994 to June 1997 on private property near Murringo, NSW Australia (34°15� S, 148°30� E). The site was primarily sheep and cattle grazing land and had a history of no fox management. Rainfall was considerably below average for much of the study. A total of 83 foxes were trapped over 3931 trapnights, of which 50 were fitted with radio-collars (23 adult and 6 juvenile females, 12 adult and 9 juvenile males) and 26 released with eartags only (all juveniles: 10 females, 16 males). Thirty-three foxes were radio-tracked using fixed towers between March 1995 and December 1996, with between 11 and 28 foxes tracked at any time. Mean home range size was 446.1 ha ± 69.8 se using 95% Minimum Convex Polygons (MCP), and 276.4 ha ± 36.3 se using 95% kernel utilisation distributions. Male home ranges defined by MCP were significantly larger than female ranges, but no significant difference was found using 95% kernels. Core ranges were estimated to be 133.4 ha ± 23.7 se using 50% MCP and 59.8 ha ± 6.1 se using 95% kernels, with no significant difference between sexes. No significant differences were found between range sizes of adults and juveniles or between years or seasons. While most home ranges were steady for the duration of the study, some foxes were observed to shift range location and 4 foxes displayed nomadic behaviour for at least some of the study. There was a high incidence of overlapping home ranges, most commonly between females or males and females but occasionally between males, but core areas were usually separate. Fully overlapping core areas were observed in 1995 but not in 1996. Juvenile foxes were significantly more likely to disperse than adults, and usually travelled further (juveniles 61.1 km 31.6 ± se; adults 5.9 km 1.1 ± se). Males and females were equally likely to disperse, and there was no significant difference in the distance travelled. The furthest distances were 285 km and 140 km, but mean distance of dispersal excluding these animals was 12.3 km ± 4.3 se (n = 13). Thorough surveys across a 16.4 km² area located 200 dens, with 68 of these active in 1995 and 96 active in 1996. Density of breeding foxes was estimated to be 0.55 and 0.52 adult foxes/km² in 1995 and 1996 respectively based on natal den counts. Density estimates based on active den counts, which include non-breeding foxes, were 0.91and 1.30 foxes/km² in 1995 and 1996 respectively. These estimates appear lower than other studies in similar habitats but this is likely due to using a half home range boundary strip around the surveyed area in the present study. Application of mark-recapture analysis found very high �recapture� rates of dens and gave a similar estimate of the total number of dens to that observed directly. Natal dens were regularly distributed across the study area, whereas active dens tended to be in clusters. There was a high turnover of which dens were used each year, but the total number of natal dens was similar across years (16 in 1995 and 17 in 1996). Natal dens were more likely to be used on repeat occasions than other dens, but not necessarily by the same vixen. Litter size based on sightings of emergent cubs was 2.8. Foxes were predominantly nocturnal, with a major peak in activity about an hour after sunset. A new method of analysing activity rhythm data using Fourier series to mathematically describe animal movements was developed, that allowed systematic identification of the cyclical components underlying overall movement patterns. General fox behaviour could be clearly described by a 24-hour and a 12-hour cyclical component when corrected for variation in daylength. The rising and setting of the sun appeared to be a major trigger underlying movement patterns. Seasonal and sex differences were observed in patterns of activity. The annual rate of increase of the fox population was found to vary around a mean of zero between June 1994 and June 1997. A major drop in fox numbers as estimated by spotlight counts occurred in the second half of 1995, but numbers recovered by the end of 1996. Kaplan-Meier analysis of radio-tagged foxes found annual adult survival was generally very high (0.56-0.96) with lowest survival between July and October. Causes of mortality were human-related outside the site and apparently of natural causes within the site. However foxes dying of natural causes outside the site were unlikely to be found. There was no overall movement of foxes into or out of the site. Immigration was detected following the drop in fox numbers in late 1995, but there was no evidence of immigration prior to this period although emigration occurred. A sensitivity analysis was conducted on the effects of a small change in life history parameters on finite rate of increase using published data as well as adult mortality data from the present study. The two most influential life-history parameters were adult and juvenile survival, while changes in fecundity and age at first reproduction had much less impact on finite rate of increase. In terms of management, in which fertility control is being considered as an alternative to lethal control, this implies that a small change in fecundity may cause less change in the rate of increase of foxes than lethal control. Foxes were culled in June 1997 on completion of the study. Estimated density using a Petersen estimate was 2.4-5.3 foxes/km² and index-manipulation-index was 1.4-3.2 foxes/km². The different methods used to cull foxes appeared to target different age groups within the population, and were generally biased in favour of younger foxes. Success at killing animals was low, leading to large standard errors in the population estimates. Stomachs of foxes shot in the Orange district were found to contain predominantly rabbit and carrion, with invertebrates present when abundant. These findings were not strictly representative of the diet of foxes in the study area, where rabbits were scarce. Foxes scavenged heavily on lamb carcasses within the study site. The quantity of fresh lamb carrion removed from a lambing paddock in winter 1996 was estimated to support 13-24 foxes, with available fresh lamb theoretically able to support 240-440 foxes. Density based on removal of fresh carcasses was estimated to be 0.83-1.5 foxes/km².

Marine flatworms are important mobile predators on hard substrate, however little is known about their life history. I recorded seven species of flatworms in Botany Bay and described a new species of flatworm Imogine lateotentare sp. nov. It is distinguished from other species in the same genus by having small, transparent and inconspicuous tentacles and continuous bands of numerous frontal and cerebral eyes. This new flatworm species was found closely associated with the barnacle Balanus variegatus (Darwin, 1854) on which it fed. Marine flatworms provide elaborate parental care to their offspring but its significance has not been experimentally confirmed. I provided quantitative measurements of the significance of parental care behaviour in Echinoplana celerrima and Stylochus pygmaeus under controlled laboratory conditions. I also examined the changes in reproductive behaviour of E. celerrima and the hatching success of their eggs when exposed to three putative flatworm egg predators. Brooding behaviour of neither species of flatworm enhanced the hatching success of their eggs and exposure of E. celerrima to the potential egg predators did not affect the timing of hatching or hatching success of its eggs. However, E. celerrima spent more time guarding their eggs when exposed to the potential egg predators. Brooding may be an innate behaviour in marine flatworms but it is not essential to their reproductive success. Marine flatworms are closely associated with sessile organisms and these assemblages are common in bays and estuaries which are subject to anthropogenic inputs from various sources. Impacts of pollutants are known for many flatworm prey species but little is known about the effects on the flatworm themselves. I examined the influence of sublethal concentrations of copper ranging from 0 to 50 ??g L-1 on the predatory and reproductive behaviour of Stylochus pygmaeus. These worms were more sensitive to low levels of copper pollution than their barnacle preys. Response of flatworms to physical stimulation, number of egg batches laid and hatching success were greatly reduced at higher copper concentrations. In areas polluted by heavy metals, flatworm populations will be affected at lower concentrations than their barnacle prey and which may alter sessile invertebrate community structure.

The effects of roads on landscapes and wildlife and their ecological processes are substantial and represent a major anthropogenic disruption to the natural environment. Current understanding of the impacts of roads for their strategic management is hampered by a lack of information on 1) the influence of the ecosystems on road effects, 2) the effects of roads on higher-order ecosystem responses (populations and communities), and 3) the overall impacts of roads on ecosystems and their wildlife (on both abiotic and biotic ecosystem components). This study used the Silver City Highway in arid New South Wales, Australia, as a model for a typical road in an arid ecosystem to investigate the ecological effects of arid-zone roads and their management. The study examined the spatial variation of soil, vegetation, kangaroo and small mammal variables in relation to the road, explored the factors contributing to these respective spatial variations, investigated the effects of arid-zone road management on vegetation, assessed the fragmentation effect of the arid-zone road on small mammals, and determined the patterns, causes and effects of kangaroo-vehicle collisions. The study revealed that the arid-zone road influenced most of the variables measured, skewed the population demographics of two kangaroo species, and altered the community composition of small mammals, with two small mammal species listed as threatened in NSW and of national significance (Sminthopsis macroura and Leggadina forresti) negatively impacted by the road. Increases in the amount of water along the road edge drove many of the subsequent effects of the arid-zone road as arid-zone flora and fauna are adapted to exploiting limited and patchily distributed resources. However, current arid-zone road management also influenced vegetation quality, microclimates around the road influenced kangaroo densities and small mammal communities, and kangaroo flight behaviour and temporal variations in traffic volume affected roadkill frequency. Together, these results suggest that roads have a high overall ecological impact in arid ecosystems. Conservation managers need to first rank the impacts of arid-zone roads in order of their conservation importance and need for mitigation, and from there, devise relevant informed management frameworks to target these impacts.

ABSTRACT Despite increasing evidence for the impact of feral cats Felis catus on native fauna in Australia, little is known of the ecology of cats, particularly factors that limit cat abundance. The ecology of the feral cat in Australia is represented by just 15 published studies on diet, only one of which has examined diet in relation to prey availability, and one study of home range behaviour. The red fox Vulpes vulpes is a significant pest to agriculture and native fauna in Australia and widespread fox removals have been proposed by the Vertebrate Biocontrol Cooperative Research Centre (VBCRC). However, there is concern that feral cats may increase compensatorily when fox populations are reduced, as has occurred in Western Australia, and therefore that predation pressure may not be alleviated on native fauna following fox control programs. This thesis is divided into two parts. First, the diet and home range size of cats is examined in relation to prey availability, and home range overlap and habitat use are determined. In the second part, several niche parameters (diet, home range and habitat use) that were potentially important resources for foxes and cats were quantified to assess the potential for competition. Avoidance and aggression between cats and foxes was examined using simultaneous radiotracking techniques and video observations. The hypothesis that foxes limit cats through interspecific competition (exploitation and interference) was then tested using a fox removal experiment. Finally, three further hypotheses were tested using a fox removal experiment to determine which factors limit feral cats at Burrendong. The four hypotheses tested were thus: i) Cats are limited independently of foxes through other factors such as food availability; ii) Foxes limit cats through interspecific competition (exploitation and/or interference); iii) Foxes limit cats through intraguild predation; iv) Cats benefit from the presence of foxes through facilitation. The diets and spatial use of feral cats were examined on agricultural land on the eastern shore of Lake Burrendong, New South Wales (32o40�S, 149o 10�E) between July 1994 and June 1997. The major land use for the area is water catchment under the agistment of sheep Ovis aries and cattle Bos taurus. The study area encompasses about 90 km2 of hilly terrain with undulating slopes that extend down to a flat foreshore area that has been extensively cleared of trees for grazing. The slopes are generally well timbered and dominated by white box Eucalyptus albens woodlands with some yellow box E. melliodora associations. Stands of cyprus pines Callitris spp. are also common. Feral cats and red foxes are established throughout the study area, and the European rabbit Oryctolagus cuniculus was abundant until the arrival of Rabbit Calicivirus Disease (RCD) in June 1996. The diet of feral cats was determined from the analysis of 499 scats. Rabbits were the staple prey of cats, with occurrence (O) in 81.6% of scats and comprising 68.4% by volume (V). Carrion (mostly eastern grey kangaroo Macropus giganteus and sheep) (O 21.5%, V 11.5%) was an important secondary food, particularly in winter and spring. Other mammalian prey included brushtail possums Trichosurus vulpecula (O 4.6%, V 2.4%), house mice Mus domesticus (O 6.2%, V 3.2%), black rats Rattus rattus (O 2.6%, V 1.4%) and a dunnart Sminthopsis sp. (probably S. murina) (O 0.2%, V 0.006%). Invertebrates (mostly Orthopterans) (O 41.5%, V 7.5%), vegetation (O 26.3%, V 3.6%), birds (O 4.2%, V 0.8%) and reptiles (O 3.4%, V 0.3%) were generally of minor importance in the diet. Few significant seasonal differences were found, although invertebrates contributed significantly less, and possums more, to the mean scat volume in winter and summer respectively. A significant dietary response was found for changes in rabbit abundance, but not for the other prey groups. Cats continued to prey heavily on rabbits after the arrival of Rabbit Calicivirus Disease, despite the relatively low numbers of rabbits. Ten months post-RCD, house mice increased in importance in the diet. However, it was not known whether this represented prey switching sensu stricto or opportunistic predation on an increased mouse population, as mouse abundance was not measured during this period. Seventy-seven cats (48 recaptures) were caught in 6762 trap nights between November 1994 and August 1996 using both cage traps and leg-hold traps. A further 18 individual cats were trapped as non-target animals by the VBCRC Fox Sterility Project and used in this study. Trapped adult cats were fitted with radio collars and their home range size, overlap and habitat use examined. Home ranges and core areas were quantified using 95% and 50% kernel utilisation distributions (KE 95 and KE 50) and minimum convex polygons (MCP 100, MCP 95, MCP 50). Four habitat types (grassland, open woodland, open forest, and mudflats) were delineated on aerial photographs and a habitat map produced using ARC/INFO. Compositional analysis was used to examine habitat preference in cats. Home range sizes of cats (n = 15, 598 fixes) in winter 1995, prior to fox removal, were similar to those reported in the only published study of cat spatial use in Australia, but larger than those recorded elsewhere. This may have reflected more dispersed food resources in Australia, although home range size was not correlated significantly with rabbit abundance. Male ranges (MCP 95 = 284 ha, n = 11) tended to be larger than females ( = 151ha, n = 4), but no differences were detected between young (1-3 years, = 271ha, n = 7) and old (>3 years, = 221ha, n = 8) cats. Cats were active both by day and night with no temporal differences being detected in range size. Both adult male and female cats tended to be solitary, although home ranges overlapped extensively. Kin groups were indicated (but not confirmed) as most inter-sexual overlap occurred between young and old cats. Habitat composition of home ranges generally reflected the availability of habitats at the study site, although cats significantly avoided mudflats. Home ranges comprised mostly open woodland and open forest habitats with smaller areas of grassland and mudflats. However, within individual home ranges, cats used grassland and open woodland habitats most often where rabbits were more abundant. Inter-individual (sex, age) or temporal (day/night) differences in habitat use were not detected. Comparison of resource use between cats and foxes indicated a large overlap in diet, home ranges and habitat use. Dietary breadths and overlaps between cats and foxes increased when rabbit availability declined in autumn and post-RCD. Dietary overlap was high overall (75%), although some resource partitioning was detected. Rabbits were more important in the diet of cats than foxes, particularly in summer, when foxes ate more grasshoppers. Carrion, invertebrates and vegetation were more important for foxes than for cats overall. Home ranges of both cats and foxes comprised mostly open woodland habitats followed by grassland, open forest and mudflats, which largely reflected their relative availabilities. However, within individual home ranges, cats showed a preference for grassland habitats. In addition, cats tended to deposit scats more often than foxes at rabbit warrens and at hollow log entrances, while foxes deposited scats more often than cats on sand plots, tracks and at dams. The large overlap in resource use between cats and foxes indicated a high potential for exploitation competition. Foxes may attempt to lessen competition by killing cats (interference competition). Three radiocollared cats were killed by foxes and aggression was observed toward cats. Home ranges overlapped extensively, but avoidance was indicated from the simultaneous radiotracking of both predators, as greater separations and lower overlaps in home ranges and core areas were recorded between species than within species. In addition, video observations suggested avoidance of carcasses by cats in the presence of foxes. The hypothesis that foxes limit feral cats through interspecific competition was then tested using a fox removal experiment. Foxes were reduced at two of the four sites from October 1995 using �1080� baiting and spotlight shooting by the VBCRC Predator-Prey project. Resource use and abundance of cats were compared before and after fox removal and between treated and untreated sites. Although no increase in cat abundance followed the removal of foxes, significant behavioural changes by cats strongly suggested interspecific competition operating via exploitation and interference. Exploitation competition was supported by the increased consumption of carrion by cats at the treated sites after fox removal, while support for interference competition came from the increased use of grassland habitats at night after fox removal. The direction of the resource shifts to more prey-rich habitats indicated asymmetry in the relationship between the two predator species. Although the null hypothesis of no limitation of cats by foxes could not be rejected, as no increase in cat abundance was recorded after fox removal, interspecific competition was considered to be the most likely mechanism limiting feral cats at Burrendong. Intraguild predation was not indicated as no cat remains were found in any of the 343 fox scats or 255 fox stomachs that were examined. In addition, minimal evidence was found for facilitation between cats and foxes, or for food limitation. The potential for foxes to limit cats, as shown in this study, indicates that cats need to be considered in future fox control operations. Integrated pest management, where foxes, cats and rabbits are controlled together, is strongly proposed if the objective is to safeguard native fauna in Australia. Further research is required to improve the effectiveness of current techniques for censusing cat populations, particularly in forested areas. This is essential for monitoring the effectiveness of control campaigns and quantifying factors that limit cat populations, and ultimately for effective protection of susceptible native fauna.

Thesis (PhD)--Macquarie University, Division of Environmental and Life Sciences, Dept. of Biological Sciences, 2005.
Bibliography: p. 178-203.
Introduction -- Study sites -- Leaf characteristics and resource availability -- Insect herbivory and resource availability -- Insect communities and resource availability -- Influence of resource availability on recovery from herbivory -- Conclusions.
This project used the resource availability hypothesis (Coley et al., 1985) as a framework for investigating the relationship between resource availability (as defined by soil nutrients), leaf traits, insect herbivore damage and insect community structure. According to the hypothesis, plants from low resource environments should be better-defended, have longer leaf lifespans and slower growth rates than plants from higher resource environments. Higher resource plant species are expected to suffer higher levels of herbivory and recover faster from herbivory than low resource plant species (Coley et al. 1985). A corollary to this hypothesis is that plants from higher resource sites should support greater densities of insect herbivores than low resource species. Comparisons between high and low resource sites were made in terms of: (i) leaf traits of mature and immature leaves; (ii) phenology of leaf maturation; (iii) herbivore damage in the field and laboratory; (iv) diversity and abundance of herbivorous insect fauna; and (v) ability to recover from herbivory.
Mode of access: World Wide Web.
243 p. ill., maps

Densities and behaviour of Noisy Friarbirds Philemon corniculatus and Red Wattlebirds Anthochaera carunculata were measured during 1992 and 1993 at six sites along an east-west transect through central New South Wales from the Central Coast through to the Central Western Slopes, and at Goobang National Park from 1993 to 1996. Both P. corniculatus and A. carunculata were found to be mostly canopy foragers with occasional forays into the shrub layer when food resources became available there. Flower-probing and foliage gleaning comprised the bulk of foraging behaviour. Most of the food resources used by these honeyeaters were seasonally unreliable and unpredictable, so that they needed to shift between foods and track them over hundreds of kilometres. A strong relationship was found between the densities of honeyeaters and the density of flowering trees at both regional and local scales. Sites on the western slopes were more important for nectar during winter and spring, while sites on the tablelands provided a greater diversity of foods over all seasons. When foraging at foliage, both honeyeaters were found to preferentially select Eucalyptus punctata. These two honeyeaters are very mobile and appear to cope within the fragmented landscape. Their ecological role as plant pollinators, seed dispersers and insect population limiters may have increased proportionally due to habitat fragmentation compared with less mobile species with similar ecological roles. Hence they may also have become more important in maintaining habitat patch quality
Doctor of Philosophy (PhD)

Patterns in the floristic composition, stand structure, species richness and environmental characteristics of plant communities at a number of spatial scales were examined in Ku-ring-gai Chase National Park, New South Wales. Vegetation patterns in eastern Australia have often been related primarily to a single environmental variable, soil phosphorus concentration. This study examines the 'single nutrient' hypothesis regarding the distribution of plant species. If soil phosphorus concentration is the majot factor affecting the distribution of plant species, then this should be highly correlated with spatial patterns in the floristic composition of plant communities within the study area. Floristic composition was determined as the frequencies of all vascular species occuring within duplicate 500 m2 quadrants from fifty sites within the Park. Environmental data consisted of 21 variables, including soil physical and chemical characteristics, from each quadrant. The patterns in floristic composition and environmental factors are described and the relationships between composition and environment were examined. through indirect and direct gradient analyses. The measured environmental factors showed strong correlations with floristic patterns; however, two scales of species distributions were apparent: between and within soil type. Direct gradient analyses of composition and environmental data showed soil phosphorus concentration was inadequate in explaining the observed patterns in floristic composition of plant communities are a response to complex multivariable environmental gradients. The structural characteristics of vegetation stands were examined through the development of a multivariate approach to the classification of stand structure. This multivariate approach is essentially a modification of an existing scheme utilising foliage projective cover of various recognisable strata within the strands. Multivariate classification and ordinations of plant communities based on structural characteristics showed strong correspondence to that obtained by compositional analyses. The complex multivariable gradient hypothesis is supported from results examining stand structure-environment relationships. The relationship between species richness and richness of three growth-form types (tree, shrubs, and herbs) and environmental variables were examined through generalised linear models. The measured environmental variables showed strong relationships with species richness, consistent with the results found multivariately with floristic composition and stand structure. No single measured environmental variable adequately predicted the observed patterns in species richness, rather species richness showed strong relationships with complex multivariable environmental gradients. This study clearly demonstrates the the 'single-nutrient' or 'phosphorus' hypothesis is inadequate in explaining all the patterns in the various components of vegetation within Ku-ring-gai Chase National Park. The complex multivariable environmental gradient hypothesis suggested by the relationships between floristic composition and environmental variables is supported by the relationships exhibited by two other attributes of vegetation communities: stand structure and species richness. Further studies testing the significance of the complex multivariable environmental gradient hypothesis are required.

Thesis by publication -- 8 co-authored articles.
Thesis (PhD)--Macquarie University, Division of Environmental and Life Sciences, Department of Biological Sciences.
Includes bibliographical references.
Preface -- Management issues of urban common brushtail possums (Trichosurus vulpecula): a loved or hated neighbour -- Effects of deslorelin implants on reproduction in the common brushtail possum (Trichosurus vulpecula) -- Brushtail possums (Trichosurus vulpecula) in metropolotan Sydney: population biology and response to contraceptive implants -- Strategic survey for Toxoplasma gondii and Neospora caninum in the common brushtail possum (Trichosurus vulpecula) from urban Sydney, Australia -- Leptospirosis serology in the common brushtail possum (Trichosurus vulpecula) from urban Sydney, Australia -- Conclusions.
The common brushtail possum (Trichosurus vulpecula) is indeed a common inhabitant of many Australian citites, and one of the few marsupials that has adapted well to the urban environment. Their close proximity to people provides a great opportunity to experience native wildlife in the backyard, however, their utilization of house roofs, bold behaviour and appetite for garden plants often leads to conflict with householders. Population numbers are sufficiently high to require ongoing management to minimise negative impacts for humans and brushtail possums alike in a socially acceptable manner. The aim of this thesis was to identify current management issues and address the need for improved and novel management strategies. The potential of slow-release implants, containing the GnRH agonist deslorelin, as a contraceptive agent for brushtail possums was tested on a captive population. Males appeared resistant to treatment, but deslorelin was found to inhibit reproduction in female brushtail possums for at least one breeding season, making it a promising tool to control fertility in some wild populations. A further aim was to trial deslorelin implants on a wild urban population, to collect more information about the urban biology of this species and to point out issues which have previously not been addressed. Close proximity and interaction of urban brushtail possums with humans and their domestic animals can increase the risk of disease exposure and transmission and influence the health of wild populations. Serosurveys showed that animals were readily exposed to Leptospira spp. and Toxoplasma gondii. This thesis also provides the first data on brushtail possum dispersal in urban areas, knowledge which is highly relevant to the development of management strategies such as fertility control. The findings from this research broaden our knowledge about urban brushtail possums and should assist wildlife authorities in developing alternative or improved management procedures.
Mode of access: World Wide Web.
xxv, 287 p. ill., maps

The principle objective of this study was to examine the potential impact of the Cat, Fox and dog on native species, in particular those that are prey of these predators, in native forests that are principally managed for the production of timber in south-east NSW. This was examined initially by investigating the relative effectiveness of four techniques for surveying the Cat, Fox and dog, viz:- (i) spotlighting, (ii) scat surveys, (iii) scent-station surveys; and (iv) hair-tube surveys. The results from the surveys provided information on: (i) the distribution of the Cat, Fox and dog in relation to roads, forest edges and remote forest environments; and (ii) the relative abundance of the Fox and dog in the region. The results from the surveys were also used to investigate habitat attributes that potentially influence the abundance of the Fox and dog in the region. The extent that the Cat, Fox and dog used habitat in the vicinity of roads and habitat away from roads also was investigated using hair-tubes and radiotracking techniques. Scat surveys provided information on the diet of the Fox and dog. Results from diet analyses and spotlight surveys were used to explore whether the Fox and dog were opportunistic or selective in their choice of prey. The relative risk of prey species to predation by the Fox and dog also was assessed. Finally, the data collected in this study provided an opportunity to explore the efficacy of poison-baiting for reducing the abundance of the Fox and dog in the region during the period of the study. v The study region was stratified using environmental domains (Richards et al. 1990) to place it in a broader environmental context and to identify the environmental variation within it. To provide a comparative basis for field research, the environmental domains were grouped into two areas, viz:- the coastal and escarpment area. Within each of the two areas 15 sites were identified for survey purposes. Spotlighting, scat collection, scent-stations and hair-tubes were found not to be equally effective for surveying the Cat, Fox and dog in the region. Spotlighting was found to be the least effective method for detecting these species. Scat surveys provided information on the distribution and relative abundance of the Fox and dog, but was ineffective for detecting the Cat. Hair-tubes detected the Cat and dog, but not the Fox, despite observations of the Fox close to hair-tubes. With the exception of data collected from scat surveys, statistical analyses were limited due to small sample sizes. As a consequence, some of the analyses are descriptive and should be considered as an exploratory investigation only. The dog was found to be equally abundant both in the coastal and the escarpment areas, and significantly more abundant and widespread than the Fox. The Fox was significantly more abundant in the coastal area. The abundance of the Fox and dog varied significantly between survey periods and there was significant variation in their abundance within each area. Following poison-baiting, the abundance of the Fox and dog decreased at sites where poison-baiting occurred. However, this was not statistically significant. Hair-tube surveys detected the Cat and dog on roads, in edge habitat (areas within 500 m of a road) and in areas more than 1.5 km from roads (or remote areas). The Fox was also detected in all three habitat types from scats and by observation. In addition, radio-tracking found that one Cat preferred habitat more than 500 m from roads. The remains of 29 mammal species were found in the scats of the Fox and dog during the study. Large mammal species (i.e., those with an adult body weight greater than 10 kg), and in particular the Swamp Wallaby, were the most common prey of the dog. Large mammals formed more than 50% of its diet. Correspondingly, these species were also found to be most at risk from predation by the dog. Medium-sized marrunal species (i.e., those with an adult body weight between 0.75-10 kg) formed approximately one-third of the diet of the dog. The remainder of the diet consisted of small mammal species (i.e., those with an adult body weight less than 0.75 kg). Small mammals were the most common prey of the Fox. The Dusky Antechinus, Brown Antechinus, Bush Rat and Black Rat each formed more than 5% of the diet of the Fox. These species were also found to be more at risk from predation by the Fox than large and medium-sized mammals. Approximately one-third of the diet of the Fox consisted of medium-sized mammals, in particular the Rabbit, closely followed by the Common Ringtail Possum. The extent to which the Fox and the dog were opportunistic or selective predators was not clear from this study. Overall, the most common large and medium-sized species in the diet<> of the dog and Fox also were relatively more abundant (e.g., the Swamp Wallaby, brushtail possums and Common Ringtail Possum). This suggested that the dog and Fox hunted these species in proportion to their abundance (i.e., opportunistically). However, this relationship was not always consistent. The abundance of the dog, rainfall, and time since logging were found to be significantly correlated with the abundance of the Fox in the region. A number of factors, such as resource partitioning of prey by the dog and Fox, potentially greater abundances of small mammals in drier forests, and relative ease of foraging by the Fox in recently logged and perhaps unlogged forests, may have partially explained these results. No habitat attributes were found to explain significantly the abundance of the dog in the region. The results from this study clearly indicate that the Cat, Fox and dog are widespread in the region and the Fox and dog are relatively abundant. The evidence from this study and other studies suggest that in forest environments most mammal species, with the exception of bats and some arboreal species, are potential prey for these predators. This may have consequences for the survival of native species, particularly Critical Weight Range (CWR) species (i.e., those with an adult body weight between 35-5500 g) and ground-dwelling mammals that are rare and/ or endangered, in these forests. As small mammals were found to be most at risk from predation by the Fox, it may be a greater threat to CWR species and species that are rare and/ or endangered. It is possible that high levels of predation by feral predators can suppress small populations to the extent that they cannot recover (i.e., predator-pit) and thus are more prone to extinction from stochastic events. In the absence of knowledge, such as the range of prey densities over which feral predators exert a regulatory role, endangered and naturally rare prey species may be able to persist in the presence of the Cat, Fox and dog provided that: (i) relatively dense understorey vegetation (i.e., their habitat) is maintained to provide refugia; and (ii) feral predator populations are effectively controlled to minimise their potential impact.

The Menindee Lakes are a series of shallow floodplain depressions on the Lower Darling River, approximately 300 river kilometres upstream from the confluence with the River Murray, in southeastern Australia. The system is the fourth largest water storage in the Murray-Darling Basin (1,680 Gl) and comprises of seven shallow deflation basins: Lakes Malta, Balaka, Bijiji, Tandure, Pamamaroo, Menindee, Cawndilla, and Lake Wetherell. Lake Wetherell was created by the construction of the Menindee Main Weir and subsequent flooding of the main channel of the Darling River and surrounding floodplain. Each deflation lake is individually connected to the Darling River with the exception of Lake Cawndilla, which is connected to Lake Menindee by Morton Boolka Channel. The climate of the Menindee area is arid with a mean annual rainfall of 243.7 mm, average maximum temperature in January of 34.1° C and in July of 16.9° C. Due to the flat topography, local runoff is negligible and the impact of precipitation on the water budget of the lakes is negligible in comparison to evaporation, which exceeds 2.5 m year-1. Prior to regulation, the Menindee Lakes would fill when river levels were higher than the sill level of the feeder creeks. When river levels receded, the lakes drained back to the Darling River leaving a residual pool, which would evaporate. The Darling River is one of the most variable rivers in the world and prior to regulation the Menindee Lakes were often dry for extended periods. The large lakes (Cawndilla, Menindee, Pamamaroo and Tandure) would fill on average every once every one to two years and the longest droughts lasted five years. The small lakes (Bijiji, Balaka and Malta) filled on average every two to three years with the longest droughts lasting eleven years. Construction of the Menindee Lakes Scheme was completed in 1968 and is a series of small dams, regulators, weirs, channels and levees designed to conserve Darling River floodwaters. The main structure is the Menindee Main Weir, which raises the level of the river 12 m above the bed level, creating Lake Wetherell and filling Lakes Tandure, Bijiji, Balaka and Malta. This hydraulic head is used to gravity feed Lakes Pamamaroo, Menindee and Cawndilla. The hydrologic regime is now dictated by the operating procedures developed by the New South Wales Department of Infrastructure, Planning and Natural Resources. The priority of operations is to maximize the potential supply of water for all users and to maximize water quality within the lakes and Lower Darling River for human uses. Now the lakes are inundated for longer periods; rates of drawdown are more rapid and small to medium sized floods downstream of the scheme and in the Darling Anabranch have been eliminated. Despite increased permanency, large water level fluctuations are still common and drying cycles have not been lost entirely. Since the completion of the scheme Lake Malta has dried four times, Lake Balaka three times, Lake Bijiji twice, Lakes Tandure and Pamamaroo once, Lake Menindee five times and Lake Cawndilla four times. Of all of the lakes, Lake Malta is least impacted by regulation. The vegetation dynamics and role of the seed bank have not been extensively investigated in ephemeral systems. The seed bank provides a mechanism for species persistence through unfavourable conditions and colonisation during favourable conditions. In ephemeral lakes, large and aseasonal water level fluctuations are common which may result in long periods of unfavourable conditions. Plants growing in these environments must be able to persist through unfavourable conditions for growth and survival. The main objectives of this study were: - To investigate the seed density, species richness and composition of the seed banks of selected lakes. - To determine if there are any within lake patterns in seed bank density, species richness and composition. - Examine the effect of different water regimes on germination and recruitment from the seed bank. - Determine water regime preferences for germination and recruitment of common species. - Investigate vegetation change during an extended drought. - Determine flood tolerances of Xanthium occidentale, Cyperus gymnocaulos and Ludwigia peploides. - Investigate the interaction between nutrients and water regime on recruitment from the seed bank. No information regarding the seed banks of the Menindee Lakes was available; therefore, a reconnaissance study was undertaken. The aims of this study were to determine the seed density, floristic composition, zonation with respect to elevation, differences between and within lakes and germination strategy (pattern through time) of Lake Malta, Bijiji and Menindee seed banks. Results showed that the seed bank of each lake had a different floristic composition and Lake Menindee had a depauperate seed bank (Lake Malta 27 species and 6,300-43,983 seeds m-2, Lake Bijiji 24 species and 2243-27,417 seeds m-2 and Lake Menindee one species and 117-233 seeds m-2). Within each lake, the seed density, species richness and composition was spatially variable but no zonation with respect to elevation was observed. In Lake Bijiji, the sampling site on the northern shore of the lake had a significantly less dense and less species rich seed bank than the other locations; however, this was not present in Lake Malta. Over 90% of the total germination from the seed bank from all lakes occurred in the first six weeks. This study also provided evidence that the seed bank around the edges of the lakes was concentrated in zones of organic matter deposition (strandlines). The seed bank density and species composition of the strandlines and adjacent sediment was investigated in Lakes Cawndilla, Menindee, Tandure (large highly regulated lakes) and Malta (a small lake minimally impacted by regulation). Three hypotheses were tested in this study: 1. The strandline will have a denser and more species rich seed bank. 2. The strandline provides favourable microsites for germination and recruitment. 3. All species present in the seed bank will bet hedge. The strandline seed banks of Lakes Cawndilla (strandline 25,753 seeds m-2 and adjacent sediment 2,730 seeds m-2), Menindee (strandline 7,427 seeds m-2 and adjacent sediment 646 seeds m-2) and Tandure (strandline 8,006 seeds m-2 and adjacent sediment 2,178 seeds m-2) were significantly denser and more species rich than the adjacent sediment, whereas there was large, species rich seed bank outside the strandline in Lake Malta strandline (70,180 seeds m-2 and adjacent sediment 54,266 seeds m-2). The organic component of the strandline may act to reduce evaporation from the soil and provide a favourable microsite for germination and recruitment. Of the 58 species present in all seed banks 37 bet hedged (had persistent seed banks). The effect of water regime on recruitment from the seed bank and the optimal water regime for germination and recruitment of common species were investigated in a pond experiment. This experiment had three aims: 1. To test the hypothesis that different water regimes will give rise to different plant communities from the same seed bank. 2. Determine optimal water regimes for germination and recruitment of common species. 3. To formulate a testable conceptual model describing recruitment from the seed bank under different, controlled water regimes. Different water regimes did give rise to different plant communities from the same seed bank. Myriophyllum verrucosum was the only species that germinated whilst submerged. All other species required exposed soil with high soil moisture to germinate. All terrestrial and floodplain species died if flooded, however several amphibious species were present that persisted whilst flooded, despite requiring exposed soil for germination. The conceptual model consisted of eight states (dependant on whether the soil was exposed or inundated, soil moisture content, duration of inundation and species present) that predicted which species would be present in each of the states (providing they were present in the seed bank). A series of surveys to investigate recruitment from the seed bank in the field during a period of extended drought was undertaken over 488 days. This study had four aims: 1. To investigate the relationship between the extant vegetation and selected environmental variables. 2. To test a conceptual model that predicts how the environment changes with fluctuating water levels. The model consists of five states (windows of opportunity) that the system switches between; depending water level, elevation and the species present in the seed bank and extant vegetation. The five states are: window of opportunity closed due to inundation, window of opportunity open for germination establishment and reproduction (exposed soil with high moisture content in the top 7.5 cm), window of opportunity closed for germination but open for establishment and reproduction (low soil moisture in the top 7.5 cm), window of opportunity closed for germination and establishment but open for reproduction (top 15 cm low soil moisture) and all windows of opportunity closed because the soil is dry (low soil moisture to 40 cm). 3. To test the part of the conceptual model derived from the pond experiment. 4. To investigate the change in the germinable seed bank as the window of opportunity for germination opens, plants recruit and replenish the seed bank. This aim tests the hypothesis that the species that recruit will reflect the seed bank before the window of opportunity for germination opens, then when the window of opportunity for germination opens the seed bank will become less similar and then recover (reflect the recruited vegetation) after the species present have replenished the seed bank. The floristic composition of Lake Malta was correlated with sediment exposure time and clay content, Lake Balaka with sediment exposure time, soil moisture and clay content, Lake Wetherell with elevation, canopy cover and elevation of the water relative to the quadrat and Lake Menindee with sediment exposure time, soil moisture, elevation and clay content. The floristic composition of Lake Cawndilla was not correlated with any of the measured environmental variables. As water levels fell the window of opportunity for germination opened once the sediment was exposed and closed when the sediment surface dried. The window of opportunity for establishment and reproduction did not close until the sediment dried further. For the most desiccation tolerant species the window of opportunity for growth and reproduction remained open. If the species composition of the seed bank was known, the pond model predicted the potential floristic composition. However, it did not take into account sediment exposure time. Extended drought in the Darling catchment meant that the lakes did not fill during the study period and the effect of flooding could not be investigated in the field. Therefore, a pond experiment to test the effect of flooding on Xanthium occidentale, Cyperus gymnocaulos and Ludwigia peploides was undertaken. Three hypotheses were tested: 1. Xanthium occidentale when top flooded for more than two weeks will die. Plants partially flooded will survive, increase above ground to below ground biomass ratio and grow when water levels fall. 2. Cyperus gymnocaulos when top flooded for two weeks will show no adverse effects and grow when water levels fall. When top flooded for more than two weeks the above ground biomass will senesce and resprout when water levels fall. Plants partially flooded will show no adverse effects. 3. Ludwigia peploides when top flooded will rapidly increase above ground biomass in order to reach the water surface. Each species generally responded as hypothesised. Xanthium occidentale also produced adventitious roots and lost stem rigidity when partially flooded. Cyperus gymnocaulos showed reduced growth rates when partially flooded compared to plants that were not flooded. Water regime is only one factor that may influence the floristic composition derived from the seed bank. A pond experiment was undertaken to test the hypothesis that the combination of different soil nutrient concentrations and water regime will give rise to different plant communities from the same seed bank. The effect of different nutrient loadings however, had no effect on floristic composition and the differences could be explained by differences in water regime. The sediment seed banks of the Menindee Lakes provide a mechanism for survival through droughts and floods. They are spatially variable and the strandline accounted for the majority of seed around the edges of the large regulated lakes. All but one species present in the seed banks of all lakes sampled required exposed sediment with high soil moisture to germinate and many species were very desiccation tolerant (especially terrestrial and floodplain species). Most species were intolerant to flooding as juvenile or adults; however, there were a few amphibious species present. Water regime influences the floristic composition derived from the seed bank but soil texture is also an important factor, whereas nutrients appeared to have no effect.
Thesis (Ph.D.)--School of Earth and Environmental Studies, 2004.

The Menindee Lakes are a series of shallow floodplain depressions on the Lower Darling River, approximately 300 river kilometres upstream from the confluence with the River Murray, in southeastern Australia. The system is the fourth largest water storage in the Murray-Darling Basin (1,680 Gl) and comprises of seven shallow deflation basins: Lakes Malta, Balaka, Bijiji, Tandure, Pamamaroo, Menindee, Cawndilla, and Lake Wetherell. Lake Wetherell was created by the construction of the Menindee Main Weir and subsequent flooding of the main channel of the Darling River and surrounding floodplain. Each deflation lake is individually connected to the Darling River with the exception of Lake Cawndilla, which is connected to Lake Menindee by Morton Boolka Channel. The climate of the Menindee area is arid with a mean annual rainfall of 243.7 mm, average maximum temperature in January of 34.1° C and in July of 16.9° C. Due to the flat topography, local runoff is negligible and the impact of precipitation on the water budget of the lakes is negligible in comparison to evaporation, which exceeds 2.5 m year-1. Prior to regulation, the Menindee Lakes would fill when river levels were higher than the sill level of the feeder creeks. When river levels receded, the lakes drained back to the Darling River leaving a residual pool, which would evaporate. The Darling River is one of the most variable rivers in the world and prior to regulation the Menindee Lakes were often dry for extended periods. The large lakes (Cawndilla, Menindee, Pamamaroo and Tandure) would fill on average every once every one to two years and the longest droughts lasted five years. The small lakes (Bijiji, Balaka and Malta) filled on average every two to three years with the longest droughts lasting eleven years. Construction of the Menindee Lakes Scheme was completed in 1968 and is a series of small dams, regulators, weirs, channels and levees designed to conserve Darling River floodwaters. The main structure is the Menindee Main Weir, which raises the level of the river 12 m above the bed level, creating Lake Wetherell and filling Lakes Tandure, Bijiji, Balaka and Malta. This hydraulic head is used to gravity feed Lakes Pamamaroo, Menindee and Cawndilla. The hydrologic regime is now dictated by the operating procedures developed by the New South Wales Department of Infrastructure, Planning and Natural Resources. The priority of operations is to maximize the potential supply of water for all users and to maximize water quality within the lakes and Lower Darling River for human uses. Now the lakes are inundated for longer periods; rates of drawdown are more rapid and small to medium sized floods downstream of the scheme and in the Darling Anabranch have been eliminated. Despite increased permanency, large water level fluctuations are still common and drying cycles have not been lost entirely. Since the completion of the scheme Lake Malta has dried four times, Lake Balaka three times, Lake Bijiji twice, Lakes Tandure and Pamamaroo once, Lake Menindee five times and Lake Cawndilla four times. Of all of the lakes, Lake Malta is least impacted by regulation. The vegetation dynamics and role of the seed bank have not been extensively investigated in ephemeral systems. The seed bank provides a mechanism for species persistence through unfavourable conditions and colonisation during favourable conditions. In ephemeral lakes, large and aseasonal water level fluctuations are common which may result in long periods of unfavourable conditions. Plants growing in these environments must be able to persist through unfavourable conditions for growth and survival. The main objectives of this study were: - To investigate the seed density, species richness and composition of the seed banks of selected lakes. - To determine if there are any within lake patterns in seed bank density, species richness and composition. - Examine the effect of different water regimes on germination and recruitment from the seed bank. - Determine water regime preferences for germination and recruitment of common species. - Investigate vegetation change during an extended drought. - Determine flood tolerances of Xanthium occidentale, Cyperus gymnocaulos and Ludwigia peploides. - Investigate the interaction between nutrients and water regime on recruitment from the seed bank. No information regarding the seed banks of the Menindee Lakes was available; therefore, a reconnaissance study was undertaken. The aims of this study were to determine the seed density, floristic composition, zonation with respect to elevation, differences between and within lakes and germination strategy (pattern through time) of Lake Malta, Bijiji and Menindee seed banks. Results showed that the seed bank of each lake had a different floristic composition and Lake Menindee had a depauperate seed bank (Lake Malta 27 species and 6,300-43,983 seeds m-2, Lake Bijiji 24 species and 2243-27,417 seeds m-2 and Lake Menindee one species and 117-233 seeds m-2). Within each lake, the seed density, species richness and composition was spatially variable but no zonation with respect to elevation was observed. In Lake Bijiji, the sampling site on the northern shore of the lake had a significantly less dense and less species rich seed bank than the other locations; however, this was not present in Lake Malta. Over 90% of the total germination from the seed bank from all lakes occurred in the first six weeks. This study also provided evidence that the seed bank around the edges of the lakes was concentrated in zones of organic matter deposition (strandlines). The seed bank density and species composition of the strandlines and adjacent sediment was investigated in Lakes Cawndilla, Menindee, Tandure (large highly regulated lakes) and Malta (a small lake minimally impacted by regulation). Three hypotheses were tested in this study: 1. The strandline will have a denser and more species rich seed bank. 2. The strandline provides favourable microsites for germination and recruitment. 3. All species present in the seed bank will bet hedge. The strandline seed banks of Lakes Cawndilla (strandline 25,753 seeds m-2 and adjacent sediment 2,730 seeds m-2), Menindee (strandline 7,427 seeds m-2 and adjacent sediment 646 seeds m-2) and Tandure (strandline 8,006 seeds m-2 and adjacent sediment 2,178 seeds m-2) were significantly denser and more species rich than the adjacent sediment, whereas there was large, species rich seed bank outside the strandline in Lake Malta strandline (70,180 seeds m-2 and adjacent sediment 54,266 seeds m-2). The organic component of the strandline may act to reduce evaporation from the soil and provide a favourable microsite for germination and recruitment. Of the 58 species present in all seed banks 37 bet hedged (had persistent seed banks). The effect of water regime on recruitment from the seed bank and the optimal water regime for germination and recruitment of common species were investigated in a pond experiment. This experiment had three aims: 1. To test the hypothesis that different water regimes will give rise to different plant communities from the same seed bank. 2. Determine optimal water regimes for germination and recruitment of common species. 3. To formulate a testable conceptual model describing recruitment from the seed bank under different, controlled water regimes. Different water regimes did give rise to different plant communities from the same seed bank. Myriophyllum verrucosum was the only species that germinated whilst submerged. All other species required exposed soil with high soil moisture to germinate. All terrestrial and floodplain species died if flooded, however several amphibious species were present that persisted whilst flooded, despite requiring exposed soil for germination. The conceptual model consisted of eight states (dependant on whether the soil was exposed or inundated, soil moisture content, duration of inundation and species present) that predicted which species would be present in each of the states (providing they were present in the seed bank). A series of surveys to investigate recruitment from the seed bank in the field during a period of extended drought was undertaken over 488 days. This study had four aims: 1. To investigate the relationship between the extant vegetation and selected environmental variables. 2. To test a conceptual model that predicts how the environment changes with fluctuating water levels. The model consists of five states (windows of opportunity) that the system switches between; depending water level, elevation and the species present in the seed bank and extant vegetation. The five states are: window of opportunity closed due to inundation, window of opportunity open for germination establishment and reproduction (exposed soil with high moisture content in the top 7.5 cm), window of opportunity closed for germination but open for establishment and reproduction (low soil moisture in the top 7.5 cm), window of opportunity closed for germination and establishment but open for reproduction (top 15 cm low soil moisture) and all windows of opportunity closed because the soil is dry (low soil moisture to 40 cm). 3. To test the part of the conceptual model derived from the pond experiment. 4. To investigate the change in the germinable seed bank as the window of opportunity for germination opens, plants recruit and replenish the seed bank. This aim tests the hypothesis that the species that recruit will reflect the seed bank before the window of opportunity for germination opens, then when the window of opportunity for germination opens the seed bank will become less similar and then recover (reflect the recruited vegetation) after the species present have replenished the seed bank. The floristic composition of Lake Malta was correlated with sediment exposure time and clay content, Lake Balaka with sediment exposure time, soil moisture and clay content, Lake Wetherell with elevation, canopy cover and elevation of the water relative to the quadrat and Lake Menindee with sediment exposure time, soil moisture, elevation and clay content. The floristic composition of Lake Cawndilla was not correlated with any of the measured environmental variables. As water levels fell the window of opportunity for germination opened once the sediment was exposed and closed when the sediment surface dried. The window of opportunity for establishment and reproduction did not close until the sediment dried further. For the most desiccation tolerant species the window of opportunity for growth and reproduction remained open. If the species composition of the seed bank was known, the pond model predicted the potential floristic composition. However, it did not take into account sediment exposure time. Extended drought in the Darling catchment meant that the lakes did not fill during the study period and the effect of flooding could not be investigated in the field. Therefore, a pond experiment to test the effect of flooding on Xanthium occidentale, Cyperus gymnocaulos and Ludwigia peploides was undertaken. Three hypotheses were tested: 1. Xanthium occidentale when top flooded for more than two weeks will die. Plants partially flooded will survive, increase above ground to below ground biomass ratio and grow when water levels fall. 2. Cyperus gymnocaulos when top flooded for two weeks will show no adverse effects and grow when water levels fall. When top flooded for more than two weeks the above ground biomass will senesce and resprout when water levels fall. Plants partially flooded will show no adverse effects. 3. Ludwigia peploides when top flooded will rapidly increase above ground biomass in order to reach the water surface. Each species generally responded as hypothesised. Xanthium occidentale also produced adventitious roots and lost stem rigidity when partially flooded. Cyperus gymnocaulos showed reduced growth rates when partially flooded compared to plants that were not flooded. Water regime is only one factor that may influence the floristic composition derived from the seed bank. A pond experiment was undertaken to test the hypothesis that the combination of different soil nutrient concentrations and water regime will give rise to different plant communities from the same seed bank. The effect of different nutrient loadings however, had no effect on floristic composition and the differences could be explained by differences in water regime. The sediment seed banks of the Menindee Lakes provide a mechanism for survival through droughts and floods. They are spatially variable and the strandline accounted for the majority of seed around the edges of the large regulated lakes. All but one species present in the seed banks of all lakes sampled required exposed sediment with high soil moisture to germinate and many species were very desiccation tolerant (especially terrestrial and floodplain species). Most species were intolerant to flooding as juvenile or adults; however, there were a few amphibious species present. Water regime influences the floristic composition derived from the seed bank but soil texture is also an important factor, whereas nutrients appeared to have no effect.
Thesis (Ph.D.)--School of Earth and Environmental Studies, 2004.

University of Technology, Sydney. Faculty of Science.
Seahorses are iconic charismatic species that are threatened in many countries around the world with several species listed on the IUCN Red List as vulnerable or endangered. Populations of seahorses have declined through over-exploitation for traditional medicines, the aquarium trade and for curios and through loss of essential habitats. To conserve seahorse populations in the wild, they are listed on Appendix II of CITES, which controls trade by ensuring exporting countries must be able to certify that export of seahorses is not causing a decline or damage to wild populations. Within Australia, seahorses are protected in several states and also in Commonwealth waters. The focus of this study was White’s seahorse Hippocampus whitei, a medium-sized seahorse that is found occurring along the New South Wales (NSW) coast in Australia. The species is listed as ‘data deficient’ on the IUCN Red List and there is little research information available to assist in the conservation of the species. Research on H. whitei was undertaken from 2006-2009 and primarily focused on determining the species’ life history parameters, its distribution and relative abundance, habitat preferences and site fidelity, and response to marine protected area (MPA) protection and habitat modification. Research primarily occurred within Sydney Harbour and Port Stephens. Field surveys found that H. whitei is endemic to coastal estuaries along 300 km of NSW coastline. It is a medium-sized seahorse (max LT 162 mm) that displays rapid growth (Port Stephens: females L∞ = 149.2 mm and K = 2.03 per year and males L∞ = 147.9 mm and K = 2.52; Sydney Harbour: females L∞ = 139.8 mm and K= 1.28 and males L∞ = 141.6 mm and K=1.22), becomes sexually mature at approximately 6 months, and can live for up to 5 years in the wild. The species displays life-long monogamy with several pairs observed breeding over three consecutive breeding seasons, and strong site fidelity with seahorses remaining at the same site for up to 56 months for males and 49 months for females. Adult male and female H. whitei exhibited a significant preference for sponge and soft coral Dendronephthya australis habitats whilst juveniles had a strong preference for gorgonian Euplexaura sp. habitat. Hippocampus whitei in Port Stephens were significantly less abundant within the no-take MPA and there was a negative correlation with predator abundance. Long-term monitoring of H. whitei in Port Stephens found that populations declined over a period of six months for no apparent reason; however, they recovered within three years. A manipulative experiment undertaken on protective swimming nets in Sydney Harbour found H. whitei had a positive association with epibiotic growth and proximity to the sea floor. An experiment on the effects of flash photography found it had no significant effect on movements, behaviour, or site persistence of H. whitei and concluded that flash photography by divers is a safe and viable survey technique for this species. The information obtained from this study should contribute towards a reassessment of the species under the IUCN Red List and also provides the necessary data to ensure adequate management of the species within NSW waters.

Agricultural pastures are one of the most common land-cover types in fragmented terrestrial landscapes. While they may act as a 'matrix' (i.e. unable to support sustainable populations) for some species, for others they can have high conservation potential. In many parts of the world, agricultural pastures are being replaced by tree plantations, which will influence the distribution of patch-associated species and those that occur more broadly across the landscape. Understanding how species respond to landscape transformation is critical to the successful conservation of biodiversity. My thesis introduction further explores possible consequences of landscape transformation and the ecological and management context of my research (Chapter 1). I then present my systematic review, which assesses how the matrix has so far been considered in fragmentation studies on butterflies (Chapter 2). I found it was significantly more likely for studies not to include the matrix in their experimental design. This result was concerning as 80% of the papers which did consider the matrix reported that it had a negative impact on butterflies. My review highlights the need for future research to ensure the matrix is included appropriately in the experimental design of studies in fragmented landscapes. I then present empirical research on butterflies (Chapter 3) and ground-active beetles (Chapter 4) in a landscape of native Eucalyptus woodland patches surrounded by agricultural pastures and pine plantations in the southwest slopes of New South Wales, Australia. My results suggest that farmland offers resources to both taxa. Conversely, in areas where farmland has been transformed to plantation, I found significantly fewer beetles and a complete absence of butterflies. This research indicates that land-cover change could have serious implications for the successful dispersal of animals, and may lead to population isolation and/or biotic homogenisation. I further explore mechanisms driving the distribution of butterflies in this landscape by investigating movement of Heteronympha merope (common brown butterfly) at edges of eucalypt woodland, agricultural pasture and pine plantation (Chapter 5). I found individuals were less likely to approach pine edges compared to edges of farmland or eucalypt. They also were unlikely to cross pine edges, and in cases where they did cross, they always returned to the area they were released from. If released within pine, individuals actively departed. These results further support the suggestion that dense pine plantations may interrupt successful disperal for species in patchy landscapes. My thesis demonstrates the effects of landscape transformation on patch-associated species and others that occur more widely across the landscape. The lack of biodiversity supported by plantations is particularly concerning for conservation considering demands for plantation wood will result in plantation expansion in many areas worldwide. This thesis concludes by providing recommendations for improving the conservation value of plantations (Chapter 6), including; adopting earlier thinning schedules and preserving corridors of native trees or understorey vegetation. Implementing my recommendations will likely improve matrix use and patch connectivity for invertebrates and other taxa. Future research should concentrate on evaluating the effectiveness of my management recommendations for various taxa and systems (Chapter 6).

This thesis challenges the constitutive and taken-for-granted assumptions of the current dominant administrative rationalist discourse of wild dog management and control (WMDC) in New South Wales (NSW), Australia. It asks: To what extent can conflicts over WDMC in NSW be understood in terms of contending discourses and what does that imply for policy legitimacy? It isolates the storylines that emerged from substantial empirical research and examines, if and how, these storylines contributed to the dominant discourse of administrative rationalism. From the beginning of white settlement of NSW, the State and farm families worked in concert to achieve the eradication of wild dogs and dingoes. From the 1960s, however, a significant discursive turn occurred in WDMC. This occurred as a result of the contending discourses of environmentalism, ecological science, animal welfare and biosecurity. These discourses collectively afforded new meanings to dingoes, wild dogs and WDMC. Concurrently, the State drove this discursive turn through a discourse of administrative rationalism. From 1995 until 2011, a period of successive NSW Labor Governments, the State further consolidated this discursive approach. It reified 'experts' and legislatively empowered public land managers to inform, shape and promulgate the dominant discourse of WDMC through the promotion of a 'best practice' model. Within this model the individual knowledges and experiences of farm families of WDMC were subject to empirical measurement, the interpretations of public land managers and the corroboration of continuing ecological studies. The entry of new social actors closely linked to Government who actively promoted 'new' innovations and technologies in WDMC further distilled the dominance of the administrative rationalist discourse. However, the legitimacy of this approach was forcefully challenged by a growing sense of crisis in the 'Bush.' This was driven by farm families who were directly affected by the lack of WDMC on public lands, the increasing numbers of wild dogs and the devastating effect this was having on the lives of farm families. This reality was exploited mercilessly for its political capital by all political parties. Successive NSW Labor Governments consistently reiterated in storylines its financial largesse in WDMC to give legitimacy to its discursive approach. These storylines of financial expenditures in real terms however are difficult to substantiate. Ironically, the success of the administrative rationalist discourse was dependent on the continued involvement of farm families in a public planning process which pivoted on their acquiescence to a discourse that subordinated their concerns and, at the same time, relied on the widespread adoption of this model by farm families across NSW. This has proved deeply problematic. Overwhelmingly, at public WDMC meetings farm families rejected the State's reliance on administrative rationalism and a chorus of voices reflected the significant gap that existed between the political and policy rhetoric of WDMC and the lived reality. Nevertheless, successive attempts by farm families have so far failed to dislodge the dominant discourse of WDMC.

Research Doctorate - Doctor of Philosophy (PhD)
In temperate New South Wales, most fish species in the family Labridae have not previously been investigated with available knowledge restricted primarily to photographic identification guides providing brief notes on species distribution, habitat preferences and identification. This information is inadequate for assessing the impact of labrid harvesting on rocky reef systems and for making informed management decisions for the protection of these fishes. Therefore, this study aimed to fill some of the significant gaps in the understanding of labrid assemblages associated with rocky reefs of temperate eastern Australia. This was accomplished by concentrating primarily on three species - Ophthalmolepis lineolatus, Notolabrus gymnogenis and Pictilabrus laticlavius - which are abundant and co-occur in shallow waters (less than 20 m depth) on the central coast of New South Wales. The methods used in this study included SCUBA surveys of labrid assemblages; in situ observations of labrid behaviour on SCUBA; and acquisition of labrid specimens for the extraction of intestines, gonads and otoliths, and for measurements of fish weight and length.
Labrids were found to be the most species rich family in the study region and were the most abundant of all non-planktivorous fishes. Overall, a higher number of labrid species and a higher number of labrid individuals occurred in sponge garden habitat (15-22 m depth) compared to fringe (3-7 m) and barrens (8-15 m), owing to greater densities of O. lineolatus, Austrolabrus gymnogenis and Eupetrichthyes angustipes. The common labrids, N. gymnogenis, Achoerodus viridis and P. laticlavius, occurred at higher densities in fringe habitat due mostly to a higher representation of juveniles in this habitat. The effect of habitat on labrid assemblages was subject to small-scale variation between sites (separated by hundreds of metres) and experienced temporal changes due primarily to a substantial increase in the abundance of recruits coinciding with late summer and autumn (April-May). Behavioural observations revealed that the three focal species differed substantially in their spatial structure. O. lineolatus were found to be temporary reef residents using home ranges in excess of 2500 m2 for periods of up to 1 year before permanently emigrating outside these temporary home ranges. In contrast, N. gymnogenis exhibit strong site fidelity to reef patches of less than 600 m2 in which they remain for periods in excess of 2 years. Reef patches are shared by up to at least 10 juvenile and female individuals and a single, highly territorial male in a mating system suggestive of resource defence polygyny. An understanding of the spatial structure of P. laticlavius was constrained by its cryptic behaviour, but behavioural observations suggest this species is home ranging and establishes temporary territories for the purpose of feeding and/or reproduction. Intensive ethological observations allowed for the description and quantifying of several major behaviours in which all species typically engaged including encounters and interactions with other fishes, lying, use of shelter, side-swiping, bending, gaping, cleaning by clingfishes (Gobiesocidae) and colour change. The occurrence of these behaviours often demonstrated substantial differences among species (e.g. lying, shelter and bending) and/or experienced shifts with ontogeny (e.g. interactions and area usage). These trends generally remained consistent at different times of the day and periods of the year, and at both locations. Dietary analyses revealed O. lineolatus, N. gymnogenis and P. laticlavius are generalist carnivores feeding on a variety of benthic invertebrates including polychaetes, amphipods, decapods, gastropods, bivalves, polyplacophorans, echinoderms and cirripedes. Differences in the volumetric contribution of prey items in the guts of each species showed that food resources are partitioned among species and observations of foraging behaviour demonstrated a partitioning of microhabitats used for feeding. Ontogenetic shifts in diet and feeding microhabitats demonstrate that food resources are further partitioned within a species. However, overall morphological and behavioural similarities within a species results in greater competition occurring among individuals of the same species than among individuals of different species. This was reflected in higher rates of intra-specific interactions compared with interactions between labrid individuals of different species. Observations of feeding episodes revealed the bite rates of all species were typically unaffected by the time of day and period of year in which sampling occurred, but a location effect occurred for O. lineolatus and P. laticlavius. A reduction in bite rate with ontogeny occurred for N. gymnogenis. The population structure of the three species suggests each exhibits the typical labrid reproductive strategy of protogynous hermaphroditism. O. lineolatus and N. gymnogenis are both monandrous species, but the occurrence of some P. laticlavius males at small sizes and young ages suggests this species may be diandrous. Similarities occurred between O. lineolatus and N. gymnogenis in the size/age at which individuals sexually matured (c.a. 180 mm, 2 years) and changed sex (c.a. 280 mm, 4.6 years), but these events occurred at substantially smaller sizes (95 and 138 mm, respectively) and younger ages (les than 0.9 and 1.9 years, respectively) in P. laticlavius. Sectioned otoliths were used to determine that the longevity of O. lineolatus, N. gymnogenis and P. laticlavius was at least 13.4, 9.6 and 4.8 years, respectively. Ages were validated using marginal increment analysis. Timing of reproduction in each species was asynchronous with peaks in the reproductive activity occurring in late summer to early autumn (February-March) for O. lineolatus, mid winter (July) for N. gymnogenis and mid spring to early summer (October-December) in P. laticlavius.

Research Doctorate - Doctor of Philosophy (PhD)
In temperate New South Wales, most fish species in the family Labridae have not previously been investigated with available knowledge restricted primarily to photographic identification guides providing brief notes on species distribution, habitat preferences and identification. This information is inadequate for assessing the impact of labrid harvesting on rocky reef systems and for making informed management decisions for the protection of these fishes. Therefore, this study aimed to fill some of the significant gaps in the understanding of labrid assemblages associated with rocky reefs of temperate eastern Australia. This was accomplished by concentrating primarily on three species - Ophthalmolepis lineolatus, Notolabrus gymnogenis and Pictilabrus laticlavius - which are abundant and co-occur in shallow waters (less than 20 m depth) on the central coast of New South Wales. The methods used in this study included SCUBA surveys of labrid assemblages; in situ observations of labrid behaviour on SCUBA; and acquisition of labrid specimens for the extraction of intestines, gonads and otoliths, and for measurements of fish weight and length.
Labrids were found to be the most species rich family in the study region and were the most abundant of all non-planktivorous fishes. Overall, a higher number of labrid species and a higher number of labrid individuals occurred in sponge garden habitat (15-22 m depth) compared to fringe (3-7 m) and barrens (8-15 m), owing to greater densities of O. lineolatus, Austrolabrus gymnogenis and Eupetrichthyes angustipes. The common labrids, N. gymnogenis, Achoerodus viridis and P. laticlavius, occurred at higher densities in fringe habitat due mostly to a higher representation of juveniles in this habitat. The effect of habitat on labrid assemblages was subject to small-scale variation between sites (separated by hundreds of metres) and experienced temporal changes due primarily to a substantial increase in the abundance of recruits coinciding with late summer and autumn (April-May). Behavioural observations revealed that the three focal species differed substantially in their spatial structure. O. lineolatus were found to be temporary reef residents using home ranges in excess of 2500 m2 for periods of up to 1 year before permanently emigrating outside these temporary home ranges. In contrast, N. gymnogenis exhibit strong site fidelity to reef patches of less than 600 m2 in which they remain for periods in excess of 2 years. Reef patches are shared by up to at least 10 juvenile and female individuals and a single, highly territorial male in a mating system suggestive of resource defence polygyny. An understanding of the spatial structure of P. laticlavius was constrained by its cryptic behaviour, but behavioural observations suggest this species is home ranging and establishes temporary territories for the purpose of feeding and/or reproduction. Intensive ethological observations allowed for the description and quantifying of several major behaviours in which all species typically engaged including encounters and interactions with other fishes, lying, use of shelter, side-swiping, bending, gaping, cleaning by clingfishes (Gobiesocidae) and colour change. The occurrence of these behaviours often demonstrated substantial differences among species (e.g. lying, shelter and bending) and/or experienced shifts with ontogeny (e.g. interactions and area usage). These trends generally remained consistent at different times of the day and periods of the year, and at both locations. Dietary analyses revealed O. lineolatus, N. gymnogenis and P. laticlavius are generalist carnivores feeding on a variety of benthic invertebrates including polychaetes, amphipods, decapods, gastropods, bivalves, polyplacophorans, echinoderms and cirripedes. Differences in the volumetric contribution of prey items in the guts of each species showed that food resources are partitioned among species and observations of foraging behaviour demonstrated a partitioning of microhabitats used for feeding. Ontogenetic shifts in diet and feeding microhabitats demonstrate that food resources are further partitioned within a species. However, overall morphological and behavioural similarities within a species results in greater competition occurring among individuals of the same species than among individuals of different species. This was reflected in higher rates of intra-specific interactions compared with interactions between labrid individuals of different species. Observations of feeding episodes revealed the bite rates of all species were typically unaffected by the time of day and period of year in which sampling occurred, but a location effect occurred for O. lineolatus and P. laticlavius. A reduction in bite rate with ontogeny occurred for N. gymnogenis. The population structure of the three species suggests each exhibits the typical labrid reproductive strategy of protogynous hermaphroditism. O. lineolatus and N. gymnogenis are both monandrous species, but the occurrence of some P. laticlavius males at small sizes and young ages suggests this species may be diandrous. Similarities occurred between O. lineolatus and N. gymnogenis in the size/age at which individuals sexually matured (c.a. 180 mm, 2 years) and changed sex (c.a. 280 mm, 4.6 years), but these events occurred at substantially smaller sizes (95 and 138 mm, respectively) and younger ages (les than 0.9 and 1.9 years, respectively) in P. laticlavius. Sectioned otoliths were used to determine that the longevity of O. lineolatus, N. gymnogenis and P. laticlavius was at least 13.4, 9.6 and 4.8 years, respectively. Ages were validated using marginal increment analysis. Timing of reproduction in each species was asynchronous with peaks in the reproductive activity occurring in late summer to early autumn (February-March) for O. lineolatus, mid winter (July) for N. gymnogenis and mid spring to early summer (October-December) in P. laticlavius.

L.W. Braithwaite and co-researchers hypothesised that the population density and diversity of the arboreal marsupial fauna of the eucalypt forests near Eden, New South Wales were primarily determined by the concentrations of nitrogen, phosphorus and potassium in the mature foliage of the eucalypts. I investigated this hypothesis in relation to the Greater Glider Petauroides votans. The first main objective of my study was to examine why population densities of P. votans are low in eucalypt forests with relatively low concentrations of nutrients in their mature foliage and high in eucalypt forests with relatively high concentrations of nutrients in their mature foliage. Initially, several a priori hypotheses were proposed that could account for the observed population densities of P. votans in these forests, and these were tested at two forest sites in south-eastern N.S.W. by studying and comparing the ecology of P. votans at these sites. One site of 24.6 ha at Wadbilliga carried four species of eucalypt (E. dalrympleana, E. fastigata, E. radiata, E. viminalis}. These had high concentrations of N and P in their mature foliage when compared to the range of values known for foliar N and P in this genus. The other site of 50.1 ha was at Morton and consisted of 40.3 ha of two species of eucalypts, E. gummifera and E. piperita, which formed 'forest type A'. Two smaller areas, termed 'forest types B and C', within the Morton site also supported other eucalypt species, E. sieberi at forest type B and E. consideniana, E.pellita and E. sieberi at forest type C. The nutrient concentration in the mature foliage at Morton was generally lower than at Wadbilliga. Basal area and height of the eucalypts, and the relative concentrations of N and P in their mature foliage suggested an apparent decline in forest site foliage suggested an apparent decline in forest site productivity from Wadbilliga through Morton forest types C, B and A. The change in the ratio of Symphyomyrtus to Monocalyptus eucalypts across these forests also was consistent with the presence of a decline in productivity. Many aspects of the social organisation of P. volans were related to this decline. There productivity from Wadbilliga through Morton forest types C, B and A. The change in the ratio of Symphyomyrtus to Monocalyptus eucalypts across these forests also was consistent with the presence of a decline in productivity. Many aspects of the social organisation of P. volans were related to this decline. There was a marked difference in the distribution of resident adult P. volans at the two sites. Gliders at Wadbilliga had a relatively even distribution across the site and most of the site was permanently occupied. In contrast, gliders at Morton had an extremely clumped distribution. The majority of the site was unoccupied (forest type A) and resident animals were restricted to forest types B and C which appeared to be the only favourable habitats within the site. The population density of P. volans did not appear to be related to forest site productivity. Based on the entire area of the site, the number of resident adult P. volans per hectare was 0.18 at Morton; but on the basis of the area of forest apparently suitable for occupation the population density of gliders was 0.89 animals ha-l in forest type B and 1.67 animals ha-l in forest type C. This was then higher than the population density of P. volans at Wadbilliga (0.88 animals ha-l). In contrast, the annual fecundity of the populations of P. volans was related to forest site productivity. Resident animals at Wadbilliga and Morton forest type C successfully raised young during each year of the study but those in Morton forest type B did not, although their social cycle was comparable to gliders elsewhere. Neither Wadbilliga nor Morton appeared to have experienced major disturbances such as wildfire in recent years, and neither predation nor the availability of den sites appeared to influence the distribution of resident gliders. The majority of data on the behaviour and feeding ecology of P. volans were consistent with the following observations. The observed distribution and fecundity of P. volans in each forest appeared to be related to the availability of high-quality food and this factor was an important determinant of habitat quality. At Morton, for example, the amount of such foods in forest type A was considered to be insufficient to support resident P. volans. Although high-quality food was available in forest type B, the amount of this food, at least during the study, was insufficient for successful production of offspring by resident P. volans. The foraging behaviour of P. volans at both sites differed little. All gliders attempted to maintain a high intake of new leaf growth in their diet in all seasons so foraging was closely related to the spatial and temporal availability of this food. Female P. volans at Wadbilliga and Morton forest type C, for example, spent less time foraging and were able to meet the majority of their annual food requirements from a smaller area of forest compared to females in Morton forest type B. As a consequence, females at Wadbilliga and Morton forest type C also probably expended less energy foraging compared to those in Morton forest type B. These data, combined with those on forest site productivity and eucalypt phenologies, were consistent with the hypothesis that the availability of high-quality food was higher at Wadbilliga and Morton forest type C compared to that at Morton forest type B and particularly Morton forest type A. P. volans consistently foraged for and browsed eucalypt foliage that was high in nitrogen concentration. However, my data were insufficient to implicate foliar nitrogen as the ultimate factor determining browse selection by this species. Clearly, many other foliar constituents, either independent of or in association with nitrogen, may be implicated in browse selection and influence the dietary quality of foliage for P. volans. New data on aspects of the ecology of P. volans that are relevant to its management are presented. A polygyny threshold model that may account for all of the known data on the distribution, population fecundity and mating associations (i.e. monogamy or facultative monogamy) exhibited by P. volans throughout its range is given. Application of this model may have considerable potential for identifying the high-quality habitat required by P. volans. Finally, areas warranting further research are outlined

University of Technology, Sydney, 2001.
The study of place was often divided between the spatial interests of geographers and local historians intent on constructing heroic lineages. In the period of accelerated globalization however, discrete discourses on time and space are no longer tenable. Histories of place engage the transdisciplinary approach of recent scholarship in understanding the complexities and fluidity of the world in which we live. Places are constructed out of the enmeshing of the material, social and cultural. The reasons why people migrate both within and to particular places are also critical to the ongoing perceptions of that place, and the dynamics by which local communities operate within global networks. This thesis is an historical study of a recent sewage ocean outfall dispute between residents and the local council at Emerald Beach, in the Coffs Harbour region of New South Wales' Mid-North Coast. Alongside documentary sources, it uses oral testimony to examine the factors that contributed to people's understanding of their place, and the processes that resulted in the public contestation over that place. It argues that the positions taken in the sewage dispute cannot simply be perceived as a function of individual residents' responses within a bounded local context, but were a result of the complex processes of internal migration to the region since colonisation, and especially since the 1970s, that brought competing visions for the same place. In exploring the historical traces of the dispute, the thesis examines the first wave of non-Aboriginal migration to the coastal hinterland before turning attention to the second intensive wave of migration in the postwar period. Attention shifted away from the hinterland to the coast, and the chapters examine competing uses for the coast as local born residents, tourists and the influx of new settlers from the 1970s brought diverse dreams for the warm North Coast. In particular, the sewage conflict that grew into the direct-action protests at Emerald Beach provides clear insights into the flows of migration and settlement that led to the particular mix of people who fought for their divergent conceptions of place as critical to their lifestyle and residency. Without examining historical representations of places and events, conflict situations such as the sewage dispute at Emerald Beach cannot be fully illuminated. By demonstrating the force of internal migration on perceptions of, and contestation within place, this thesis provides one framework from which other places might be investigated.

Rapid bioassessment techniques used for aquatic macroinvertebrate and plants in wetlands were tested in New South Wales, Australia. Wetlands surveyed ranged from coastal wetlands in the North and Central parts of the State, to tableland wetlands west of Sydney. Wetlands varied in dominant vegetation, hydrology, substrate and level of human impairment. Different options for sampling (mesh size, live-picking times, quadrat size, number of samples or quadrats) and analysis (taxonomic resolution, transformations, biotic indices, multivariate and univariate analyses) are compared to determine optimal sampling effort and evaluate the effects of errors or variability. Results show that, for wetlands of New South Wales, sampling procedures developed and tested in streams and other regions of Australia may not be the most efficient. Using the data from 21 wetlands in New South Wales, a number of analytical techniques were evaluated for the effects of errors. Results show that species-level multivariate analysis is more sensitive in detecting less obvious differences between wetlands (i.e., small effect sizes), while family-level analyses are more appropriate for large effect sizes. A modified waterplant index was developed that is simpler and has a wider application than the other Australian options available. Inherent problems in each index tested were addressed. The results show that the process of summarising a large amount of information into a single value will result in the loss of both information and variability between samples and this cumulative effect of error may effect the assessment of wetland condition. The practical outcome of this thesis is a set of standardised steps to assess wetland quality using biological assemblages. The results show that protocols and indices for rivers are not directly transferable to palustrine, vegetation dominated wetlands. I present protocols that are more appropriate to wetlands and recognise that each protocol would need to be adapted for each wetland type. Despite the need for flexible protocols, I promote the need for a standard approach to wetland sampling and the need for consideration of the effects of errors in sampling designs. This study highlights the need for more research on the response of specific stressors to wetlands flora and fauna. The results from this study also show that wetland macroinvertebrates and plant communities can be used as surrogates in multivariate analyses for detecting large differences between wetlands (wetland types) but that impact assessment requires more detailed investigations including species identification and careful consideration of the choice of reference and control sites. In conclusion I emphasise the need for scientific rigour in the use of biological indicators and consideration of the effects of errors and implications to sampling designs.
Doctor of Philosophy (PhD)

Although the importance of fire management for biodiversity conservation is increasingly being recognised, little is known about the relationship between fire regimes and plant diversity in Australia’s temperate grassy woodland ecosystems. This project sought to address this gap in the woodlands of Western Sydney’s Cumberland Plain. Aspects of vegetation dynamics were investigated through six studies, mostly in shale-based Cumberland Plain Woodland (CPW) remnants. Results indicate that fire frequency profoundly affects both vegetation composition and structure. The influence of fire cycles was most readily apparent in the shrub layer. Findings from the six studies were synthesized into a state and transition model which allows exploration of management actions. Interfire intervals between 4 and 12 years are predicted to maintain Themeda woodland with both Bursaria thickets and open areas, and obligate seeder shrubs. Variable intervals across time and space within these thresholds should maintain much of the landscape at fuel levels compatible with property protection; fuel loads in CPW peak well below those in woodlands on sandstone. Low fire frequency remnants dominated by Bursaria retain many conservation values, but are likely to support lower abundances of obligate seeder shrubs and open patch herbs, and to be more weed-prone, than remnants burnt once or twice a decade. Experimentation with one or two short interfire intervals may be appropriate in long unburnt CPW.
Doctor of Philosophy (PhD)

Murray cod Maccullochella peelii peelii is an iconic freshwater angling species that has suffered declines in abundance and is now listed as a nationally vulnerable species. Despite recognition of the need for biological knowledge to provide future management directions, little is known of its ecology. This thesis examines that ecology to provide new knowledge and recommendations for improved conservation management. (For complete abstract open document)

In this thesis, aspects of the reproductive biology of four Banksia species that display in various combinations all the life histories currently recognised in the genus were compared. Species like banksias, from fire prone regions of the world are typically characterised by life histories (traits and organs) that in reference to fire response allow them to be classified as seeders or sprouters. Plants killed by fire and that rely on seed for regeneration are called seeders and those that have the capacity to survive fire and produce vegetative sprouts are called sprouters. The species are Banksia ericifolia, Banksia integrifolia, Banksia oblongifolia, and Banksia serrata. The study was conducted in the Sydney region of Australia, which was arbitrarily divided into North, Central, and Southern provinces for sampling across species. It has been generally hypothesised that several traits are likely to be associated with seeders and sprouters. However, these traits were not always clearly apparent from the author’s studies. It is argued one reason for the anomalies in the expected associated traits is a result of a tendency to assume a evolutionary history that is based on fire as being the primary selection pressure.
Doctor of Philosophy (PhD)