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Behavioural Adaptation Of A Bird From Transient Wetland Specialist To An Urban Resident, John Martin, Kristine O. French, Richard Major

Faculty of Science - Papers (Archive)

Dramatic population increases of the native white ibis in urban areas have resulted in their classification as a nuisance species. In response to community and industry complaints, land managers have attempted to deter the growing population by destroying ibis nests and eggs over the last twenty years. However, our understanding of ibis ecology is poor and a question of particular importance for management is whether ibis show sufficient site fidelity to justify site-level management of nuisance populations. Ibis in non-urban areas have been observed to be highly transient and capable of moving hundreds of kilometres. In urban areas the population …

Spatial Modelling Of Benthic Cover Using Remote Sensing Data In The Aldabra Lagoon, Western Indian Ocean, Sarah Hamylton, Tom Spencer, A Hagan

Faculty of Science - Papers (Archive)

Spatially explicit ecological modelling was used to predict the distribution of 4 benthic components (live coral, carbonate sand, macroalgae and dead coral) inside the Aldabra lagoon, southern Seychelles, western Indian Ocean. Both classic ordinary least-squares and spatial autoregression techniques were carried out on a field data set of 774 spatially referenced records and 3 satellite remote sensing images to define an empirical relationship between local environmental conditions (water depth and water level variation) and benthic cover. This relationship was then used to generate a synoptic model of the spatial cover and distribution of each benthic component at the landscape (i.e. …

Are Competitive Effects Of Native Species On An Invader Mediated By Water Availability?, Tanya J. Mason, Kristine French, Ken Russell

Faculty of Science - Papers (Archive)

Question: Climate change processes could influence the dynamics of biotic interactions such as plant competition, especially in response to disturbance phenomena such as invasional processes. Are competitive effects of native species on an invadermediated bywater availability?

Location: Glasshouse facility, New SouthWales, Australia.

Methods: We constructed competitive hierarchies for a representative suite of species from coastal dune communities that have been invaded by the Asteraceae shrub, bitou (Chrysanthemoides monilifera subsp. rotundata). We used a comparative phytometer approach, where the invader species was grown with or without a suite of native species in glasshouse trials. This was used to construct competition hierarchies …

Rocky Intertidal Temperature Variability Along The Southeast Coast Of Australia: Comparing Data From In Situ Loggers, Satellite-Derived Sst And Terrestrial Weather Stations, Justin Adam Lathlean, David J. Ayre Prof, Todd E. Minchinton

Faculty of Science - Papers (Archive)

Predicting how both spatial and temporal variation in sea and air temperature influence the distribution of intertidal organisms is a pressing issue. We used data from satellites, weather stations and in situ loggers to test the hypothesis that satellite-derived sea surface temperatures (SSTs) and weather station air temperatures provide accurate estimates of ambient temperature variability on rocky intertidal shores for temporal (hourly for 1 yr) and spatial (10 m to 400 km) variation along the southeast coast of Australia. We also tested whether satellites and weather stations accurately detect the duration, frequency and number of extreme temperature events. Daily mean …

Habitat Associations Of The Long-Nosed Potoroo (Potorous Tridactylus) At Multiple Spatial Scales, Melinda A. Norton, Kristine O. French, Andrew W. Claridge

Faculty of Science - Papers (Archive)

This study examined the coarse- and fine-scale habitat preferences of the long-nosed potoroo (Potorous tridactylus) in the Southern Highlands of New South Wales, in order to inform the management of this threatened species. Live-trapping was conducted in autumn and spring, from 2005 to 2008, at two sites. Macrohabitat preferences were examined by comparing trap success with numerous habitat attributes at each trap site. In spring 2007 and autumn 2008, microhabitat use was also examined, using the spool-and-line technique and forage digging assessments. While potoroos were trapped in a wide range of macrohabitats, they displayed some preference for greater canopy and …

Accounting For Uncertainty In Ecological Analysis: The Strengths And Limitations Of Hierarchical Statistical Modeling, Noel Cressie, Catherine Calder, James Clark, Jay Ver Hoef, Christopher Wikle

Faculty of Informatics - Papers (Archive)

Analyses of ecological data should account for the uncertainty in the process(es) that generated the data. However, accounting for these uncertainties is a difficult task, since ecology is known for its complexity. Measurement and/or process errors are often the only sources of uncertainty modeled when addressing complex ecological problems, yet analyses should also account for uncertainty in sampling design, in model specification, in parameters governing the specified model, and in initial and boundary conditions. Only then can we be confident in the scientific inferences and forecasts made from an analysis. Probability and statistics provide a framework that accounts for multiple …

The Ecology Of Fire: Developments Since 1995 And Outstanding Questions, R J. Whelan

Faculty of Science - Papers (Archive)

A great deal is already known about fire ecology in Australia, because careful observation of fire effects have been informing fire management for many thousands of years and scientific study of fire ecology has been going on for over a century, especially in the fields of forestry, evolutionary ecology, and land management. In this paper, I review some of the key questions of fire ecology identified in The Ecology of Fire (1995) for which I perceive there is a need for an expanded research effort and for better communication to politicians, policy makers, land managers, and the public at large. …

Spatial Ecology Of Hatchling Water Pythons (Liasis Fuscus) In Tropical Australia, Richard Shine, Thomas R. Madsen, Ligia Pizzatto, Gregory P. Brown

Faculty of Science - Papers (Archive)

Young snakes are rarely seen in the field and little is known about their habits. mostly because they are too small for radio-telemetry (the primary method for Studying snake spatial ecology). However, the offspring or some larger species can be fitted with transmitters and we investigated the spatial ecology and habitat use of ten hatchling water pythons (Liasis fuscus: Pythonidae) in the floodplain of the Adelaide River, tropical Australia. Patterns of habitat use in the late wet season and during the dry season were similar to those of adults tracked in the same vicinity in an earlier study. Soon after …

Impacts Of A Woody Invader Vary In Different Vegetation Communities, T J. Mason, K French

Faculty of Science - Papers (Archive)

The impact of an exotic species in natural systems may be dependent not only on invader attributes but also on characteristics of the invaded community. We examined impacts of the invader bitou bush, Chrysanthemoides monilifera ssp. rotundata , in fore and hind dune communities of coastal New South Wales, Australia. We compared invader impacts on vegetation structure, richness of both native and exotic growth forms and community variability in fore and hind dunes. We found that impacts of bitou invasion were context specific: in fore dune shrublands, functionally distinct graminoid, herb and climber rather than shrub growth forms had significantly …

Coastal Systems And Low-Lying Areas, R. J. Nicholls, P. P. Wong, V. Burkett, J. Codignotto, J. Hay, R. Mclean, S. Ragoonaden, C. D. Woodroffe, P. A. O. Abuodha, J. Arblaster, B. Brown, D. Forbes, J. Hall, S. Kovats, J. Lowe, K. Mcinnes, S. Moser, S. Rupp-Armstrong, Y. Saito

Faculty of Science - Papers (Archive)

Since the IPCC Third Assessment Report (TAR), our understanding of the implications of climate change for coastal systems and low-lying areas (henceforth referred to as ‘coasts’) has increased substantially and six important policy-relevant messages have emerged. Coasts are experiencing the adverse consequences of hazards related to climate and sea level (very high confidence). Coasts are highly vulnerable to extreme events, such as storms, which impose substantial costs on coastal societies [6.2.1, 6.2.2, 6.5.2]. Annually, about 120 million people are exposed to tropical cyclone hazards, which killed 250,000 people from 1980 to 2000 [6.5.2]. Through the 20th century, global rise of …

Living In A Land Of Fire, R. J. Whelan, P. Kanowski, M. Gill, A. Andersen

Faculty of Science - Papers (Archive)

Fires are an inherent part of the Australian environment. They cannot be prevented, but the risks they pose — to life, health, property and infrastructure, production systems, and to environment values — can be minimised through systematic evaluation and strategic planning and management. Fires have a fundamental and irreplaceable role in sustaining many of Australia’s natural ecosystems and ecological processes, and they are a valuable tool for achieving many land management objectives. However, if they are too frequent or too infrequent, too severe or too mild, or mistimed, they can erode ecosystem ‘health’ and biodiversity and compromise other land management …

Climate Change Manipulations Show Antarctic Flora Is More Strongly Affected By Elevated Nutrients Than Water, J. Wasley, Sharon A. Robinson, C. E. Lovelock, M. Popp

Faculty of Science - Papers (Archive)

Climate change is expected to affect the high latitudes first and most severely, rendering Antarctica one of the most significant baseline environments for the study of global climate change. The indirect effects of climate warming, including changes to the availability of key environmental resources, such as water and nutrients, are likely to have a greater impact upon continental Antarctic terrestrial ecosystems than the effects of fluctuations in temperature alone. To investigate the likely impacts of a wetter climate on Antarctic terrestrial communities a multi-season, manipulative field experiment was conducted in the floristically important Windmill Islands region of East Antarctica. Four …

The Ecology Of Fire – Developments Since 1995 And Outstanding Questions, R. J. Whelan

Faculty of Science - Papers (Archive)

Extract - Bushfire is on the agenda more than ever… internationally. The attention of the public and politicians has been captured by extensive media coverage on big fires in the last 5 years: Portugal, France, California, Colorado, South Africa, Indonesia, the Amazon – and 2001-02 and 2002-03 in SE Australia. The various enquiries that have followed these fire events, at least in Australia (e.g. the NSW Joint Select Committee on Bushfires 2002, the Victorian Government’s Inquiry into the 2002-2003 Victorian Bushfires – Esplin et al. 2003, the House of Representatives Select Committee Inquiry into the Recent Australian Bushfires – Nairn …

Structure And Dynamics Of Sponge-Dominated Assemblages On Exposed And Sheltered Temperate Reefs, D. E. Roberts, S. P. Cummins, A. R. Davis, M. G. Chapman

Faculty of Science - Papers (Archive)

There have been few studies on the structure and dynamics of sponge-dominated assemblages, despite the fact that such assemblages are vulnerable to environmental impacts from many anthropogenic disturbances. Sponges are generally slow to recruit, slow growing and long lived; hence, they may be very vulnerable to anthropogenic and natural disturbances. In order to understand how such assemblages may respond to disturbance, it is essential to measure natural patterns of spatial differences and temporal changes, so that any future impact assessments can be identified. This study quantified and contrasted patterns of abundance in sponge-dominated assemblages on deep reefs (18 to 20 …

Surface Reflectance Properties Of Antarctic Moss And Their Relationship To Plant Species, Pigment Composition And Photosynthetic Function, C. E. Lovelock, Sharon A. Robinson

Faculty of Science - Papers (Archive)

We investigated how surface reflectance properties and pigment concentrations of Antarctic moss varied over species, sites, microtopography, and with water content. We found that species had significantly different surface reflectance properties, particularly in the region of the red edge (approximately 700 nm), but this did not correlate strongly with pigment concentrations. Surface reflectance of moss also varied in the visible region and in the characteristics of the red edge over different sites. Reflectance parameters, such as the Photochemical Reflectance Index (PRI) and Cold Hard Band (CBH) were useful discriminators of site, microtopographic position and water content. The PRI was correlated …