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Aerosols from Western Australia supply micronutrient trace elements including Fe into the western shelf of Australia and further afield into the Southern and Indian Oceans. However, regional observations of atmospheric trace metal deposition are limited. Here, we applied a series of leaching experiments followed by total analysis of bulk aerosol samples to a unique time-series of aerosol samples collected in Western Australia to determine atmospheric concentrations and solubilities of Fe and V, Mn, Co, Zn, and Pb. Positive matrix factorisation analysis indicated that mineral dust, biomass burning particulates, sea salt, and industrial emissions were the major types of aerosols. Overall, natural sources dominated Fe deposition. Higher atmospheric concentrations of mineral dust (sixfold) and biomass burning emissions were observed in warmer compared to cooler months. The fraction of labile Fe (0.6–6.0%) was lower than that reported for other regions of Australia. Bushfire emissions are a temporary source of labile Fe and may cause a peak in the delivery of its more easily available forms to the ocean. Increased labile Fe deposition may result in higher ocean productivity in regions where Fe is limiting, and the effect of aerosol deposition on ocean productivity in this region requires further study.

River ecosystems receive and process vast quantities of terrestrial organic carbon, the fate of which depends strongly on microbial activity. Variation in and controls of processing rates, however, are poorly characterized at the global scale. In response, we used a peer-sourced research network and a highly standardized carbon processing assay to conduct a global-scale field experiment in greater than 1000 river and riparian sites. We found that Earth’s biomes have distinct carbon processing signatures. Slow processing is evident across latitudes, whereas rapid rates are restricted to lower latitudes. Both the mean rate and variability decline with latitude, suggesting temperature constraints toward the poles and greater roles for other environmental drivers (e.g., nutrient loading) toward the equator. These results and data set the stage for unprecedented “next-generation biomonitoring” by establishing baselines to help quantify environmental impacts to the functioning of ecosystems at a global scale.

In wet eucalypt forest with a rainforest understorey the vegetation adjacent to first order streams does not form a distinct riparian strip. This study investigated the riparian response of terrestrial ground-dwelling beetles adjacent to four such streams in Tasmania, Australia. Beetle assemblages varied more between the four sites than they did with distance from stream within sites, where they exhibited a measurable but subtle riparian response. The extent of the riparian zone varied between the four study sites, with a 1–5 m riparian zone at three sites and a gradually changing community up to 50–100 m upslope at one site. There was a trend for greater between plot variability immediately adjacent to the streams, possibly because this is a more highly disturbed environment. None of the habitat variables measured were consistently associated with riparian or upslope assemblages of beetles, probably explaining the subtlety of the beetles’ riparian response. Forest conservation efforts for terrestrial species should not necessarily be focused on the riparian zone in preference to upslope areas.

Reserve corridors in production forestry landscapes are frequently concentrated in riparian areas. This study describes the numerical response of ground-dwelling beetles to increasing distance from streams, with the aim of evaluating the effectiveness of such a bias in reserve allocation. Patterns in abundance and diversity of epigaeic beetles were quantified at four first order streams in wet eucalypt forest in Tasmania, Australia. The depth and pattern of beetles' riparian response varied between streams. Commonly trapped beetles were less abundant near to three of the four streams, and the numerical response model differed in each case. Species richness of common beetles was also lower near one of the streams. Pooled abundance and richness of rare species did not vary in response to the riparian-upslope transition. No riparian or upslope specialist species were identified among the most commonly collected species. Compared to upslope habitat, the riparian-upslope transition encompassed greater variability in species composition without actually increasing overall richness. The study findings demonstrate the need for ecosystem-specific data to optimize reserve placement, since the results were not predicted from general vegetation patterns, ecological theory, or the widely held assumption that riparian areas support greater abundance and diversity of organisms than adjacent upslope areas. Reserves encompassing more upslope habitat are recommended to complement those located in riparian areas.

This paper tells the story of how a shared vision and shared responsibility between the Library and the School of Zoology at the University of Tasmania has led to the vertical integration of information literacy into the Zoology curriculum. Lecturers have embedded meaningful and stimulating learning activities into coursework, deliberately aimed at developing students' information literacy. Students require sound information skills to undertake these activities; these skills are taught by the Liaison Librarian during specially tailored workshops incorporated into the unit teaching. Activities include: a first-year introduction to information skills and the scholarly information infrastructure; second/third year projects that require students to find 'the science' behind popular wildlife documentaries and to explore issues and controversies of scholarly communication; the introduction of EndNote to third-year students to manage information for their major research project; and advanced skills for Honours students to undertake major literature searches and manage information using EndNote. This paper discusses: the value of contributions from the different perspectives of librarians and lecturers; the importance of an iterative, incremental approach to developing students' information literacy for lifelong learning; what students think; and work that still needs to be done.

A considerable amount of research has investigated the influence of habitat structure on predator success, yet few studies have explored the implications for community structure and food-web dynamics. The relative importance of macrophyte structure and fish predation on the composition of the macroinvertebrate and periphyton communities in a lowland river was investigated using a multifactorial caging experiment. We hypothesised that: (1) fish predators are less effective in a more structurally complex macrophyte analogue; (2) strong direct and indirect effects of fish predators (e.g. trophic cascades) are less likely to occur in a structurally complex habitat; and (3) the strength of these patterns is influenced by the composition of the prevailing community assemblage. We measured the abundance and composition of the macroinvertebrate and periphyton communities associated with three different-shaped macrophyte analogues, under different fish predator treatments and at different times. Macrophyte analogue architecture had strong, consistent effects on both the macroinvertebrate and periphyton communities; both were most abundant and diverse on the most structurally complex plant analogue. In contrast, the fish predators affected only a subset of the macroinvertebrate community and there was a suggestion of minor indirect effects on periphyton community composition. Contrary to expectations, the fish predators had their strongest effects in the most structurally complex macrophyte analogue. We conclude that in this system, macrophyte shape strongly regulates the associated freshwater assemblage, resulting in a diverse community structure less likely to exhibit strong effects of fish predation.

Edge effects potentially have negative consequences for biodiversity in logging areas. In Tasmanian wet eucalypt forest, ground-dwelling beetle assemblages responded to habitat edges between mature unlogged forest and young regeneration following clearfelling. Transects of pitfall traps extended 100 m into unlogged forest and 10 m into the felled area firebreaks at four study sites (4 sites 3 transects 8 traps/transect = 96 traps). The depth of edge influence extended between 10 m and 25 m into mature forest, and the beetle assemblage was estimated to be 95% similar to interior forest at approximately 22 m from the edge. The species composition of beetles changed gradually with distance from the edge, but for practical purposes we distinguished three zones of edge response: mature forest interior extending 22 m into unlogged forest, firebreak habitat at the edge of the coupe that extends 1 m into unlogged forest, and an edge-affected mature forest zone in between. Individual species known to be characteristic of mature and young forest were of greatest indicator value in mature forest interior and firebreak habitat, respectively. Choleva TFIC sp 01 (Leiodidae), Decilaus nigronotatus, D. lateralis and D. striatus (all Curculionidae) were identified as indicator species characteristic of mature forest interior. No species were found to be characteristic of the habitat edges. These results are relevant to current management practices in Tasmanian wet eucalypt forest, in particular to the efficacy of linear reserve networks. One hundred metre wide wildlife habitat strips, when bounded by recently harvested forest, are estimated to contain a little over 50% of interior habitat not compromised by edge effects. Small patches of forest (<1 ha) retained in variable retention harvesting are predicted to contain little or no uncompromised interior habitat for ground-dwelling beetles.

Reserve corridors in production forestry landscapes are frequently concentrated in riparian areas. This study describes the numerical response of ground-dwelling beetles to increasing distance from streams, with the aim of evaluating the effectiveness of such a bias in reserve allocation. Patterns in abundance and diversity of epigaeic beetles were quantified at four first order streams in wet eucalypt forest in Tasmania, Australia. The depth and pattern of beetles' riparian response varied between streams. Commonly trapped beetles were less abundant near to three of the four streams, and the numerical response model differed in each case. Species richness of common beetles was also lower near one of the streams. Pooled abundance and richness of rare species did not vary in response to the riparian-upslope transition. No riparian or upslope specialist species were identified among the most commonly collected species. Compared to upslope habitat, the riparian-upslope transition encompassed greater variability in species composition without actually increasing overall richness. The study findings demonstrate the need for ecosystem-specific data to optimize reserve placement, since the results were not predicted from general vegetation patterns, ecological theory, or the widely held assumption that riparian areas support greater abundance and diversity of organisms than adjacent upslope areas. Reserves encompassing more upslope habitat are recommended to complement those located in riparian areas.

In Australia, riverine biodiversity (as judged by species diversity) is threatened by an array of anthropogenic effects common in industrialised countries (e.g. in-stream barriers, mining and sewage effluents, increased nutrient inputs, introduced species) as well as more diffuse, widespread phenomena characteristic of most of the arid and semi-arid areas of the world (e.g. salinisation and alteration of flows). Although much has been learned from specific case studies in the more populated areas, the nationally systematic efforts at quantifying these threats rely mostly on measures of river "condition" or "health" because measuring species diversity across areas as large as Australia is too expensive. However, these measures are incomplete representations of biodiversity, and some of the auditing processes compound other human values into their summaries of river condition or health. Furthermore, public perceptions of what rivers in Australia can deliver in terms of "ecosystem services" may not be feasible in many areas owing to the way that the Australian landscape has evolved. To avoid making the mistake of assuming that "good river health" automatically means "all biodiversity is conserved," three advances are needed: appropriate conceptual frameworks of how a given river system functions, more research that clarifies the links between processes and biodiversity, and an understanding of the historical biogeography of the river biota so that we can provide a clear context for the first two items. Substantial progress has been made in developing and adapting conceptual models of river systems, research into processes is being initiated even in some remote, sparsely populated catchments, and much has been learned about the history and distribution of the flora and fauna. Key challenges remain in consolidating reliable empirical relationships between biodiversity and the surrogate variables used to measure it, estimating the rates of biodiversity change likely to ac

A considerable amount of research has investigated the influence of habitat structure on predator success, yet few studies have explored the implications for community structure and food-web dynamics. The relative importance of macrophyte structure and fish predation on the composition of the macroinvertebrate and periphyton communities in a lowland river was investigated using a multifactorial caging experiment. We hypothesised that: (1) fish predators are less effective in a more structurally complex macrophyte analogue; (2) strong direct and indirect effects of fish predators (e.g. trophic cascades) are less likely to occur in a structurally complex habitat; and (3) the strength of these patterns is influenced by the composition of the prevailing community assemblage. We measured the abundance and composition of the macroinvertebrate and periphyton communities associated with three different-shaped macrophyte analogues, under different fish predator treatments and at different times. Macrophyte analogue architecture had strong, consistent effects on both the macroinvertebrate and periphyton communities; both were most abundant and diverse on the most structurally complex plant analogue. In contrast, the fish predators affected only a subset of the macroinvertebrate community and there was a suggestion of minor indirect effects on periphyton community composition. Contrary to expectations, the fish predators had their strongest effects in the most structurally complex macrophyte analogue. We conclude that in this system, macrophyte shape strongly regulates the associated freshwater assemblage, resulting in a diverse community structure less likely to exhibit strong effects of fish predation.

We investigated the role of freshwater macrophytes as refuge by testing the hypothesis that predators capture fewer prey in more dense and structurally complex habitats. We also tested the hypothesis that habitat structure not only affects the prey-capture success of a single predator in isolation, but also the effectiveness of two predators combined, particularly if it mediates interactions between the predators. We conducted a fully crossed four-factorial laboratory experiment using artificial plants to determine the separate quantitative (density) and qualitative (shape) components of macrophyte structure on the prey-capture success of a predatory damselfly, Ischnura heterosticta tasmanica, and the southern pygmy perch, Nannoperca australis. Contrary to our expectations, macrophyte density had no effect on the prey-capture success of either predator, but both predators were significantly less effective in the structurally complex Myriophyllum analogue than in the structurally simpler Triglochin and Eleocharis analogues. Furthermore, the greater structural complexity of Myriophyllum amplified the impact of the negative interaction between the predators on prey numbers; the habitat use by damselfly larvae in response to the presence of southern pygmy perch meant they captured less prey in Myriophyllum. These results demonstrate habitat structure can influence multiple predator effects, and support the mechanism of increased prey refuge in more structurally complex macrophytes.

Reserve corridors in production forestry landscapes are frequently concentrated in riparian areas. This study describes the numerical response of ground-dwelling beetles to increasing distance from streams, with the aim of evaluating the effectiveness of such a bias in reserve allocation. Patterns in abundance and diversity of epigaeic beetles were quantified at four first order streams in wet eucalypt forest in Tasmania, Australia. The depth and pattern of beetles' riparian response varied between streams. Commonly trapped beetles were less abundant near to three of the four streams, and the numerical response model differed in each case. Species richness of common beetles was also lower near one of the streams. Pooled abundance and richness of rare species did not vary in response to the riparian-upslope transition. No riparian or upslope specialist species were identified among the most commonly collected species. Compared to upslope habitat, the riparian-upslope transition encompassed greater variability in species composition without actually increasing overall richness. The study findings demonstrate the need for ecosystem-specific data to optimize reserve placement, since the results were not predicted from general vegetation patterns, ecological theory, or the widely held assumption that riparian areas support greater abundance and diversity of organisms than adjacent upslope areas. Reserves encompassing more upslope habitat are recommended to complement those located in riparian areas.

This paper tells the story of how a shared vision and shared responsibility between the Library and the School of Zoology at the University of Tasmania has led to the vertical integration of information literacy into the Zoology curriculum. Lecturers have embedded meaningful and stimulating learning activities into coursework, deliberately aimed at developing students' information literacy. Students require sound information skills to undertake these activities; these skills are taught by the Liaison Librarian during specially tailored workshops incorporated into the unit teaching. Activities include: a first-year introduction to information skills and the scholarly information infrastructure; second/third year projects that require students to find 'the science' behind popular wildlife documentaries and to explore issues and controversies of scholarly communication; the introduction of EndNote to third-year students to manage information for their major research project; and advanced skills for Honours students to undertake major literature searches and manage information using EndNote. This paper discusses: the value of contributions from the different perspectives of librarians and lecturers; the importance of an iterative, incremental approach to developing students' information literacy for lifelong learning; what students think; and work that still needs to be done.

The littoral zone of small off-stream water storage containing a translocated population of Galaxias auratus was sampled fortnightly at day and night with fyke nets, electrofishing and snorkelling over 3 months. Variation in population data provided by each method, including relative abundance indices, size structure, and habitat preferences, were examined. Aspects of behaviour and activity patterns were also investigated. Night sampling using all methods consistently yielded larger catches than day sampling. The size structure of catches varied, with electrofishing at night and fyke netting during the day having higher proportions of juveniles, whilst snorkelling at night and electrofishing during the day had higher proportions of adults. Fyke netting at night yielded by far the largest catches (3-fold more than other methods) and also captured balanced proportions of juveniles and adults. Galaxias auratus had a strong diel activity pattern and were most active at night. The majority of the population migrated into the littoral zone during the night and back into deeper water during the day. A small number of juveniles remained in the littoral zone and some adults sheltered in the dense cover of species-rich littoral vegetation during the day. Shores with shallow depth profiles appeared to be preferred due to higher catches in these areas using all methods. Based on the results of this study, fyke netting at night in littoral habitats is recommended for monitoring populations of G. auratus. Fyke netting is likely to be an effective method for monitoring other lacustrine galaxiid species; however, further work is required to investigate the effects of habitat variables and fish community structure on activity patterns of galaxiids, and hence their catchability with various methods, in more extensive lentic environments.

Golden galaxias Galaxias auratus (31-235 mm fork length, LF) were collected monthly from littoral habitats in Lakes Crescent and Sorell, Tasmania, Australia, between July 2000 and December 2002. Spawning habitats were identified and monitored in both lakes, and surveyed in Lake Crescent. Trends in gonado-somatic indices and reproductive stages of development indicated that gonad development in both sexes begins in midsummer and peaks in late autumn to early winter. Males mature at smaller sizes (50% at 52 mm LF) than females (50% at 76 mm LF), larger individuals are predominately females (95% of fish ≥138 mm LF), and overall male to female ratios are female biased (c. 1:2). Spawning occurs late autumn to early spring (water temperatures = 1.4-9.7°C) with peaks in spawning activity in winter (mean water temperatures <5°C). Demersal adhesive eggs (c. 1.5 mm diameter) were found on cobble substrata (c. 20-250 mm diameter) in littoral areas (c. 0.2-0.6 m deep) and fecundity of fish 71-181 mm LF ranged from 619 to 14 478 eggs. The rate of change in water level over the 20 days prior to monthly sampling was important in explaining the occurrence of spent fish and this accounted for temporal differences in spawning between the populations. Lake hydrology influences the reproductive cycle of G. auratus by possibly providing a stimulus for spawning and it controls the availability of spawning habitat in Lake Crescent. Seasonal hydrological cycles (i.e. rises during late autumn to winter) and a minimum water level of 802.20 m Australian Height Datum in Lake Crescent during autumn (above which littoral areas of cobble substratum are inundated) are critical to G. auratus populations.

Fishes belonging to the family Galaxiidae are relatively small (usually <300 mm long), freshwaterdwelling teleosts that are found on several land masses in the southern hemisphere (McDowall & Fulton 1996). Many galaxiid species have nondiadromous life histories and the distribution of some of these consists of discrete lacustrine populations (McDowall 2000; Allen, Midgley & Allen 2002). As a result of restricted or fragmented distributions, along with other impacts (e.g. introduced fish species), many lacustrine galaxiid species are considered to be threatened; hence monitoring populations for conservation purposes is a common management practice. Fyke nets are known to be effective for capturing small-sized benthic or littoral fish in lakes (Fago 1998; Krueger & Hubert 1998), including galaxiids (Rowe & Chisnall 1997; Rowe, Konui & Christie 2002). Fyke net catches of Atlantic salmon, Salmo salar L., in lakes vary seasonally, suggesting relative abundance indices based on catch data often require correction for differences in catchability (Ryan 1984). Seasonal fluctuations in fyke net catches of European perch, Perca fluviatilis L., due to spawning-related habitat shifts were also reported by Kubeka (1992). Other studies showed that cover-orientated fish species tend to have increased catchability by fyke nets because fyke nets provide cover (Krueger & Hubert 1998; Rogers, Hansen & Beard 2003).

The occurrence of golden galaxias Galaxias auratus with dermal fungal lesions in two populations was effectively modelled by the progression of gonadal stages of development. Skin lesions were found to be characteristic of fungal dermatitis and a Saprolegnia sp. was identified as the causative agent. Infection is probably linked to spawning-related factors and it is probable that saprolegniasis is associated with seasonal mortality.

Despite potentially reducing predation mortality, behavioural responses of native species to introduced predators may still have sub-lethal impacts. In video-recorded laboratory trials, we examined the effects of introduced brown trout, Salmo trutta, on the short-term behaviour of a threatened, lake-dwelling galaxiid fish and confirmed a suspected diel pattern in habitat use by this species. We found that Galaxias auratus followed a distinct diel pattern in the use of complex habitats and open water, which was significantly altered by the presence of brown trout. In trials without the introduced predator, G. auratus used complex habitats (rocks or macrophytes) during the day, and open water during the night. In trials with brown trout present, G. auratus spent significantly less time in open water and rarely ventured out of the macrophytes. However, when given the option of using only rocky substrate or open water, which is the more common situation in the lakes to which this galaxiid is endemic, the fish reduced the amount of time they spent in the open water during the night, but still spent more time in open water than when macrophytes were available. Spending the daylight hours amongst the cover of rocks or macrophytes is most likely an adaptation to reduce the risk of predation by visual predators, and the pattern of reduced use of open water habitats in the presence of brown trout is an acute response to the close proximity of the introduced predator. The difference in the nocturnal use of macrophytes and rocks when trout are present may be related to differences in feeding opportunities or success within these habitats.

1. Fish of the family Galaxiidae are restricted to the southern hemisphere where they occupy a diverse array of habitats ranging from over 2000m in elevation to sea level. Some species are diadromous and, hence, freshwater, estuarine and marine habitats are used during their life-cycle; other species complete their entire life-cycles in freshwater environments. 2. Tasmania has a diverse galaxiid fauna that accounts for 64% of native freshwater fish species found on the island. The Tasmanian galaxiid fauna is characterized by high species richness (5 genera and 16 species), endemism (11 species), restricted distributions, and non-diadromous life histories (11 species). 3. The galaxiid fauna of Tasmania has significant conservation status with 69% of species considered ‘threatened’. The conservation status of the fauna is recognized at State, national and international levels. 4. The key threats to galaxiids in Tasmania are exotic species, hydrological manipulations, restricted distributions, general habitat degradation and exploitation of stocks. 5. Although work has recently been undertaken to conserve and manage Tasmanian galaxiid populations, the fauna is still thought to be imperilled. Knowledge gaps that need to be addressed include the biology and ecology of most species (e.g. reproductive biology, life histories, habitat use and requirements) and impacts of habitat manipulations, as well as mechanisms and impacts of interactions with exotic species. Techniques to monitor accurately the status of galaxiid species and their populations need to be developed and the coexistence of some galaxiids with introduced salmonids should also be examined.

Common name: Golden galaxias. Conservation status: Rare – (Tasmanian Threatened Species Protection Act 1995); Endangered – ASFB (2003). Identification: D 7–10, A 11–12, P 14–18, vertebral count 53–56 (McDowall & Frankenberg 1981). Small scaleless salmoniform fish, maximum size: 240 mm TFL, 130 g (Hardie 2003). Colouration: golden to olive-green on dorsal surface and sides, silvery-grey on ventral surface. Back and sides are covered with round to oval black spots (McDowall & Frankenberg 1981). Drawing by Carol Kroger in Fulton (1990).

We investigated the role of freshwater macrophytes as refuge by testing the hypothesis that predators capture fewer prey in more dense and structurally complex habitats. We also tested the hypothesis that habitat structure not only affects the prey-capture success of a single predator in isolation, but also the effectiveness of two predators combined, particularly if it mediates interactions between the predators. We conducted a fully crossed four-factorial laboratory experiment using artificial plants to determine the separate quantitative (density) and qualitative (shape) components of macrophyte structure on the prey-capture success of a predatory damselfly, Ischnura heterosticta tasmanica, and the southern pygmy perch, Nannoperca australis. Contrary to our expectations, macrophyte density had no effect on the prey-capture success of either predator, but both predators were significantly less effective in the structurally complex Myriophyllum analogue than in the structurally simpler Triglochin and Eleocharis analogues. Furthermore, the greater structural complexity of Myriophyllum amplified the impact of the negative interaction between the predators on prey numbers; the habitat use by damselfly larvae in response to the presence of southern pygmy perch meant they captured less prey in Myriophyllum. These results demonstrate habitat structure can influence multiple predator effects, and support the mechanism of increased prey refuge in more structurally complex macrophytes.

Benthic ecologists have studied the distribution of animal body sizes because it is a form of 'taxon-free' classification that may be a useful metric for describing variation within and between ecological communities. In particular, the idea that the allometry of physiological and life-history traits may control species composition and relative abundances implies a functional link between body-size distributions and communities. The physical structure of aquatic habitats has often been cited as the mechanism by which habitat may determine body-size distributions in communities. However, further progress is hindered by a lack of theoretical clarity regarding the mechanisms that connect body size to the characteristics of ecological communities, leading to methods that may obscure interesting trends in body-size data. This review examines the methodological and conceptual issues hindering progress in the search for a relationship between animal body size and habitat architecture and suggests ways to resolve these issues. Problems are identified with current methods for the measurement of animal body size, the data and measures used to quantify body-size distributions and the methods used to identify patterns therein. Fundamentally, renewed emphasis on the mechanisms by which animal body sizes are influenced by habitat architecture is required to refine methodology and synthesise results from pattern-seeking and mechanistic studies.

1. The availability of complex habitats such as macrophytes may be vital in determining the outcomes of interactions between introduced predators and native prey. Introduced brown trout (Salmo trutta) have impacted numerous small native freshwater fishes in the southern hemisphere, but the potential role of complex habitats in determining the direct outcomes of brown trout - native fish interactions has not been experimentally evaluated. 2. An in-lake enclosure experiment was used to evaluate the importance of structurally complex habitats in affecting the direct impacts of brown trout on a threatened galaxiid fish. Five Galaxias auratus and a single brown trout were added to enclosures containing one of three different habitat types (artificial macrophytes, rocks and bare silt substrate). The experiment also had control enclosures without brown trout. Habitat-dependence of predation risk was assessed by analysis of G. auratus losses to predation, and stomach contents of remaining fish were analysed to determine if brown trout directly affect the feeding of G. auratus and whether this is also habitat-dependent. 3. Predation risk of G. auratus differed significantly between habitat types, with the highest mortality in enclosures with only bare silt substrate and the lowest in enclosures containing artificial macrophytes. This result highlights the importance of availability of complex habitats for trout - native fish interactions and suggests that increasing habitat degradation and loss in fresh waters may exacerbate the direct impacts of introduced predators. 4. Stomach contents analyses were restricted to fish in enclosures with artificial macrophytes and rocks, as most fish were consumed in enclosures with brown trout and only bare silt substrate. These analyses suggest that brown trout do not directly affect the feeding of G. auratus in complex habitats, but it is still unknown whether its feeding is reduced if complex habitats are unavailable.

The habitat used by animals plays an important role in their interactions with predators and prey. By using complex habitats such as areas of dense macrophyte cover in response to elevated predation risk, small fishes may reduce their foraging success. Because the threat of predation by introduced brown trout increases the use of complex habitats by the threatened Galaxias auratus (Johnston), we experimentally examined its foraging in different habitats to estimate indirect impacts of brown trout presence. The lakes in which G. auratus lives have recently become more turbid, so the experiment was also conducted under different turbidity levels. Laboratory feeding trials in which planktonic and epibenthic prey were simultaneously offered to G. auratus in the presence or absence of artificial macrophytes and at three turbidity levels (0, 50 and 100 NTU) revealed that its overall foraging success was unaffected by habitat complexity; however, in trials with artificial macrophytes, G. auratus consumed a greater proportion of planktonic prey than in the absence of artificial macrophytes. Neither overall foraging success nor prey selection by G. auratus was affected by high turbidity, indicating that water clarity does not appear to directly negatively impact its feeding. The switch in prey types would probably not be detrimental to G. auratus in the long term, and thus it appears that there is no substantial feeding cost associated with its increased use of complex habitats. It could, however, affect lower trophic levels in the lakes to which it is endemic.

Small headwater streams have a suite of physical eccentricities that distinguishes them from the rest of the river system. These differences are now recognized in the study of sediment transport and channel morphology, but their implications for other limnological disciplines are less apparent. We suggest a zonation scheme for the upper stream system that acknowledges obvious geomorphic boundaries while highlighting differences in fine-scale habitat features that are likely to be biologically relevant. The upstream heterogeneous zone (UHZ) is distinguished by a high ratio of structural-component size to stream width. Structural components include large rocks exposed from the regolith or from colluvial sources, tree roots, and woody debris, all of which are stochastically distributed and can constrain the morphology, hydraulics, and habitat distribution of small headwater streams. The high ratio of structural-component size to stream width is a geomorphic phenomenon linked to the stream's lack of competence to move the material that forms its bed and banks. It follows that the incompetence of streams within the UHZ is ultimately responsible for their greater internal physical heterogeneity than downstream reaches and is a fundamental driver of their physical structure, dynamics, and possibly, ecology. Benign hydraulic conditions in small headwater streams have the potential to uncouple the link between physical and biological heterogeneity, resulting in a faunal community made up of highly mobile generalists.

We examined the diel feeding pattern, gastric evacuation and daily ration of a lentic, endemic Tasmanian galaxiid fish, Galaxias auratus. Analysis of stomach contents and consumption estimates based on collections of fish every 3 h over three 24-h periods in summer 2002/2003 revealed that feeding always occurred during both day and night, with no obvious peaks. We also estimated the gastric evacuation rate of G. auratus in a laboratory experiment using the two prey species found to be dominant in stomachs of field-sampled fish. The relationship was best described by an exponential model, with rate parameters (R) of 0.104 and 0.081 for the evacuation of the amphipod, Austrochiltonia australis, and the cladoceran, Daphnia carinata, at water temperatures of 11.5 and 16.5 C, respectively. Daily ration of G. auratus in summer was estimated to be approximately 3% (dry body weight) using the models of Elliot & Persson and Eggers. Galaxias auratus appears to be unusual in that its feeding pattern cannot be classified as nocturnal, diurnal or crepuscular, but its gastric evacuation and daily ration estimates are still similar to other comparable Northern Hemisphere freshwater fishes.

In wet eucalypt forest with a rainforest understorey the vegetation adjacent to first order streams does not form a distinct riparian strip. This study investigated the riparian response of terrestrial ground-dwelling beetles adjacent to four such streams in Tasmania, Australia. Beetle assemblages varied more between the four sites than they did with distance from stream within sites, where they exhibited a measurable but subtle riparian response. The extent of the riparian zone varied between the four study sites, with a 1–5 m riparian zone at three sites and a gradually changing community up to 50–100 m upslope at one site. There was a trend for greater between plot variability immediately adjacent to the streams, possibly because this is a more highly disturbed environment. None of the habitat variables measured were consistently associated with riparian or upslope assemblages of beetles, probably explaining the subtlety of the beetles’ riparian response. Forest conservation efforts for terrestrial species should not necessarily be focused on the riparian zone in preference to upslope areas.

In Australia, riverine biodiversity (as judged by species diversity) is threatened by an array of anthropogenic effects common in industrialised countries (e.g. in-stream barriers, mining and sewage effluents, increased nutrient inputs, introduced species) as well as more diffuse, widespread phenomena characteristic of most of the arid and semi-arid areas of the world (e.g. salinisation and alteration of flows). Although much has been learned from specific case studies in the more populated areas, the nationally systematic efforts at quantifying these threats rely mostly on measures of river "condition" or "health" because measuring species diversity across areas as large as Australia is too expensive. However, these measures are incomplete representations of biodiversity, and some of the auditing processes compound other human values into their summaries of river condition or health. Furthermore, public perceptions of what rivers in Australia can deliver in terms of "ecosystem services" may not be feasible in many areas owing to the way that the Australian landscape has evolved. To avoid making the mistake of assuming that "good river health" automatically means "all biodiversity is conserved," three advances are needed: appropriate conceptual frameworks of how a given river system functions, more research that clarifies the links between processes and biodiversity, and an understanding of the historical biogeography of the river biota so that we can provide a clear context for the first two items. Substantial progress has been made in developing and adapting conceptual models of river systems, research into processes is being initiated even in some remote, sparsely populated catchments, and much has been learned about the history and distribution of the flora and fauna. Key challenges remain in consolidating reliable empirical relationships between biodiversity and the surrogate variables used to measure it, estimating the rates of biodiversity change likely to ac

Edge effects potentially have negative consequences for biodiversity in logging areas. In Tasmanian wet eucalypt forest, ground-dwelling beetle assemblages responded to habitat edges between mature unlogged forest and young regeneration following clearfelling. Transects of pitfall traps extended 100 m into unlogged forest and 10 m into the felled area firebreaks at four study sites (4 sites 3 transects 8 traps/transect = 96 traps). The depth of edge influence extended between 10 m and 25 m into mature forest, and the beetle assemblage was estimated to be 95% similar to interior forest at approximately 22 m from the edge. The species composition of beetles changed gradually with distance from the edge, but for practical purposes we distinguished three zones of edge response: mature forest interior extending 22 m into unlogged forest, firebreak habitat at the edge of the coupe that extends 1 m into unlogged forest, and an edge-affected mature forest zone in between. Individual species known to be characteristic of mature and young forest were of greatest indicator value in mature forest interior and firebreak habitat, respectively. Choleva TFIC sp 01 (Leiodidae), Decilaus nigronotatus, D. lateralis and D. striatus (all Curculionidae) were identified as indicator species characteristic of mature forest interior. No species were found to be characteristic of the habitat edges. These results are relevant to current management practices in Tasmanian wet eucalypt forest, in particular to the efficacy of linear reserve networks. One hundred metre wide wildlife habitat strips, when bounded by recently harvested forest, are estimated to contain a little over 50% of interior habitat not compromised by edge effects. Small patches of forest (<1 ha) retained in variable retention harvesting are predicted to contain little or no uncompromised interior habitat for ground-dwelling beetles.

A considerable amount of research has investigated the influence of habitat structure on predator success, yet few studies have explored the implications for community structure and food-web dynamics. The relative importance of macrophyte structure and fish predation on the composition of the macroinvertebrate and periphyton communities in a lowland river was investigated using a multifactorial caging experiment. We hypothesised that: (1) fish predators are less effective in a more structurally complex macrophyte analogue; (2) strong direct and indirect effects of fish predators (e.g. trophic cascades) are less likely to occur in a structurally complex habitat; and (3) the strength of these patterns is influenced by the composition of the prevailing community assemblage. We measured the abundance and composition of the macroinvertebrate and periphyton communities associated with three different-shaped macrophyte analogues, under different fish predator treatments and at different times. Macrophyte analogue architecture had strong, consistent effects on both the macroinvertebrate and periphyton communities; both were most abundant and diverse on the most structurally complex plant analogue. In contrast, the fish predators affected only a subset of the macroinvertebrate community and there was a suggestion of minor indirect effects on periphyton community composition. Contrary to expectations, the fish predators had their strongest effects in the most structurally complex macrophyte analogue. We conclude that in this system, macrophyte shape strongly regulates the associated freshwater assemblage, resulting in a diverse community structure less likely to exhibit strong effects of fish predation.

Biggs (1999) stressed that education should be about "conceptual change, not just the acquisition of knowledge". Paradoxically, however, undergraduate science units often emphasize acquiring the knowledge content of the curriculum rather than the ability to think critically. There is evidence that science students in general appear to be less and less able to read critically, or to write with clarity and purpose (Birkerts 1994); yet these are key generic skills for all science professionals. We have developed a new level 2/3 unit, Evolution, Ecology and Society, that exposes students to contemporary theories and concepts in ecology and evolutionary biology, and examines how these ideas are used to inform both scientific progress and public debate. The unit focuses on developing the students’ information literacy, their ability to assess scientific theory critically and analytically, and their communication skills. The teaching pattern is centred upon four learning modules dealing with topical issues in science. We visualise the basic module as a “learning spiral”, beginning with student choice of topic, library research, and reporting to the group on their readings, working towards critical and comparative assessment of material through discussion, oral presentations and written assignments. Student response has been overwhelmingly positive. This paper elaborates on the learning strategies employed in this unit, which may easily be extrapolated to other discipline areas.

Information literacy ‘enables learners to engage critically with content and extend their investigations, become more self-directed, and assume greater control over their own learning’ (Council of Australian University Librarians 2001). Such skills are, therefore, a key element of undergraduate learning, a foundation for research activities, and a basis for lifelong learning within the workplace. A number of key generic graduate attributes can collectively be described as information literacy skills (ILS). These include: • a capacity to recognise the need for information and determine the nature and extent of the information needed; • a capacity to access required information effectively and efficiently; • the ability to evaluate information and its sources critically; and • the ability to create new knowledge by integrating prior knowledge and new understandings. The acquisition of such skills is an integral part of becoming a professional scientist, and there is an increasing impetus to include more overt teaching of such skills within the undergraduate degree (Parker 2003). It is acknowledged that the most effective learning outcomes occur when generic skills are an integral part of teaching within the discipline and taught to all students in a structured and progressive manner (Shapiro and Hughes 1996). Indeed, based on their own experiences of teaching ILS within the School of Zoology at the University of Tasmania (UTas), Dearden, Jones, Richardson and Barmuta (2004) have suggested that students’ acquisition of ILS should be incremental, iterative, embedded and assessed, as also proposed by Lupton (2002). Yet how can we determine what skills our students already possess, and at what level? And how can we best teach and assess their learning of information skills within the context of our own discipline?

Reserve corridors in production forestry landscapes are frequently concentrated in riparian areas. This study describes the numerical response of ground-dwelling beetles to increasing distance from streams, with the aim of evaluating the effectiveness of such a bias in reserve allocation. Patterns in abundance and diversity of epigaeic beetles were quantified at four first order streams in wet eucalypt forest in Tasmania, Australia. The depth and pattern of beetles' riparian response varied between streams. Commonly trapped beetles were less abundant near to three of the four streams, and the numerical response model differed in each case. Species richness of common beetles was also lower near one of the streams. Pooled abundance and richness of rare species did not vary in response to the riparian-upslope transition. No riparian or upslope specialist species were identified among the most commonly collected species. Compared to upslope habitat, the riparian-upslope transition encompassed greater variability in species composition without actually increasing overall richness. The study findings demonstrate the need for ecosystem-specific data to optimize reserve placement, since the results were not predicted from general vegetation patterns, ecological theory, or the widely held assumption that riparian areas support greater abundance and diversity of organisms than adjacent upslope areas. Reserves encompassing more upslope habitat are recommended to complement those located in riparian areas.

This paper tells the story of how a shared vision and shared responsibility between the Library and the School of Zoology at the University of Tasmania has led to the vertical integration of information literacy into the Zoology curriculum. Lecturers have embedded meaningful and stimulating learning activities into coursework, deliberately aimed at developing students' information literacy. Students require sound information skills to undertake these activities; these skills are taught by the Liaison Librarian during specially tailored workshops incorporated into the unit teaching. Activities include: a first-year introduction to information skills and the scholarly information infrastructure; second/third year projects that require students to find 'the science' behind popular wildlife documentaries and to explore issues and controversies of scholarly communication; the introduction of EndNote to third-year students to manage information for their major research project; and advanced skills for Honours students to undertake major literature searches and manage information using EndNote. This paper discusses: the value of contributions from the different perspectives of librarians and lecturers; the importance of an iterative, incremental approach to developing students' information literacy for lifelong learning; what students think; and work that still needs to be done.

This report describes the results of a research project conducted under the Coast and Cleans Seas program of the Natural Heritage Trust fund. It provides a summary and assessment of water quality parameters, as indicators of estuarine health, in 22 selected Tasmanian estuaries. Information is summarised on both a State wide and individual estuary basis.

This paper tells the story of how a shared vision and shared responsibility between the Library and the School of Zoology at the University of Tasmania has led to the vertical integration of information literacy into the Zoology curriculum. Lecturers have embedded meaningful and stimulating learning activities into coursework, deliberately aimed at developing students' information literacy. Students require sound information skills to undertake these activities; these skills are taught by the Liaison Librarian during specially tailored workshops incorporated into the unit teaching. Activities include: a first-year introduction to information skills and the scholarly information infrastructure; second/third year projects that require students to find 'the science' behind popular wildlife documentaries and to explore issues and controversies of scholarly communication; the introduction of EndNote to third-year students to manage information for their major research project; and advanced skills for Honours students to undertake major literature searches and manage information using EndNote. This paper discusses: the value of contributions from the different perspectives of librarians and lecturers; the importance of an iterative, incremental approach to developing students' information literacy for lifelong learning; what students think; and work that still needs to be done.

This report describes the results of a research project conducted under the Coast and Cleans Seas program of the Natural Heritage Trust fund. It provides a summary and assessment of water quality parameters, as indicators of estuarine health, in 22 selected Tasmanian estuaries. Information is summarised on both a State wide and individual estuary basis.

This report describes the results of a research project conducted under the Coast and Cleans Seas program of the Natural Heritage Trust fund. It provides a summary and assessment of water quality parameters, as indicators of estuarine health, in 22 selected Tasmanian estuaries. Information is summarised on both a State wide and individual estuary basis.