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Heidelberg, Australia

The Arthur Rylah Institute for Environmental Research is the biodiversity research organisation for the Department of Environment and Primary Industries of the government of Victoria, Australia. It provides advice on ecologically sustainable land and water management issues and with regard to threatened native flora and fauna. It is named after Sir Arthur Rylah, a long-serving Victorian politician and deputy state premier in the 1950s and 1960s. The institute was initially part of the Victorian Department of Natural Resources and Environment. However, in 2002 the Institute was transferred over to the newly formed Department of Sustainability and Environment. Wikipedia.

Adams M.,South Australian Museum | Adams M.,University of Adelaide | Raadik T.A.,Arthur Rylah Institute for Environmental Research | Raadik T.A.,University of Canberra | And 2 more authors.
Systematic Biology

Several recent estimates of global biodiversity have concluded that the total number of species on Earth lies near the lower end of the wide range touted in previous decades. However, none of these recent estimates formally explore the real elephant in the room, namely, what proportion of species are taxonomically invisible to conventional assessments, and thus, as undiagnosed cryptic species, remain uncountable until revealed by multi-gene molecular assessments. Here we explore the significance and extent of so-called hyper-cryptic species complexes, using the Australian freshwater fish Galaxias olidus as a proxy for any organism whose taxonomy ought to be largely finalized when compared to those in little-studied or morphologically undifferentiated groups. Our comprehensive allozyme (838 fish for 54 putative loci), mtDNA (557 fish for 605 bp of cytb), and morphological (1963-3389 vouchers for 17-58 characters) assessment of this species across its broad geographic range revealed a 1500% increase in species-level biodiversity, and suggested that additional taxa may remain undiscovered. Importantly, while all 15 candidate species were morphologically diagnosable a posteriori from one another, single-gene DNA barcoding proved largely unsuccessful as an a priori method for species identification. These results lead us to draw two strong inferences of relevance to estimates of global biodiversity. First, hyper-cryptic complexes are likely to be common in many organismal groups. Second, no assessment of species numbers can be considered best practice in the molecular age unless it explicitly includes estimates of the extent of cryptic and hyper-cryptic biodiversity. [Galaxiidae; global estimates; hyper-diverse; mountain galaxias; species counts; species richness.] © 2014 The Author(s) 2014. All rights reserved. For Permissions, please email: journals.permissions@oup.com. Source

Koehn J.D.,Arthur Rylah Institute for Environmental Research | Lintermans M.,University of Canberra
Endangered Species Research

The Native Fish Strategy (NFS) for the Murray-Darling Basin, south-eastern Australia, provides a whole-of-fish-community approach and coordinated direction for the rehabilitation of its severely degraded native fish populations. Together with actions outlined in recovery plans for threatened species, the NFS addresses priority threats identified for native fishes with the aim to rehabilitate native fish populations to 60% (current populations are estimated to be at about 10%) of the levels that existed prior to European settlement. The NFS has a 50 yr time frame and coordinates actions across 6 different management jurisdictions. A key component of the NFS is the engagement of communities and stakeholders, with this being undertaken, in particular, by the use of dedicated coordinators and the development of 'demonstration reaches' where rehabilitation can be undertaken using multiple actions, with community involvement. The NFS is supported by targeted research projects and monitoring within an adaptive management framework. The NFS provides an effective partnership model where central coordination, coupled with focused jurisdictional actions, can deliver benefits to all governments. It synthesises and disseminates knowledge, integrates research and management and catalyses actions for priority problems. The need, objectives, evolution and development, achievements, strengths and weaknesses of the NFS are presented. The NFS approach would be suitable for many large river basins throughout the world. © Inter-Research 2012. Source

Choquenot D.,University of Canberra | Forsyth D.M.,Arthur Rylah Institute for Environmental Research

The exploitation ecosystems hypothesis (EEH) proposes that 1) plant biomass reflects the primary productivity of an ecosystem modified by the regulating effect of herbivory, and 2) herbivore abundance reflects the productivity of plants modified by the regulating effect of predation. Primary productivity thus determines the number of trophic levels in an ecosystem and the extent to which bottom-up and top-down regulation influence the biomass ratios of adjacent and non-adjacent trophic levels (i.e. trophic cascading). We constructed an interactive model of plant (pasture), herbivore (red kangaroo Macropus rufus) and predator (dingo Canis lupus dingo), a system in which trophic cascades have been suggested to occur, and used it to test the effects of increasing stochastic variation in primary productivity and dingo culling on predictions of the EEH. The model contained four feedback loops: the predator-herbivore and herbivore-plant feedback loops, and the predator and plant density-dependent feedback loops. The equilibrium conditions along the primary productivity gradient reproduced the three zones of trophic dynamics predicted by the EEH, plus an additional zone at productivities above which the maximum density of a predator is achieved due to social regulation: that zone is characterized by increasing herbivore density and decreasing plant biomass. Culling dingoes produced trophic cascades that were strongly attenuated at primary productivities below which the maximum density of dingoes was attained. Results were robust to uncertainty in kangaroo off-take by dingoes and to the efficacy of dingo culling, but prey switching by dingoes from red kangaroos to reptiles would weaken trophic cascades. We conclude that social regulation of carnivores has important implications for expression of the EEH and trophic cascades, and that attenuation of trophic cascades increases with increasing stochasticity in primary productivity. Our model also provides a framework for understanding the conditions in which dingo-mediated trophic cascades might be expected to occur, and generates testable predictions about the effects of higher dingo densities (e.g. by stopping culling or reintroduction to former range) on kangaroo and pasture dynamics. © 2013 The Authors. Source

Macdonald J.I.,Arthur Rylah Institute for Environmental Research | Crook D.A.,Arthur Rylah Institute for Environmental Research
Marine Ecology Progress Series

Retracing movements of euryhaline fishes using otolith chemistry analysis is a complex task, requiring detailed knowledge of the relationships between otolith and water chemistry for the target species and how these relationships change across dynamic environmental gradients in estuaries. In a controlled laboratory experiment, we quantified relationships between salinity and Sr:Ca and Ba:Ca ratios in ambient water and otoliths in euryhaline Australian bass Macquaria novemaculeata across a salinity gradient encompassing freshwater to marine values (i.e. 0.5, 5, 21 and 38%). Results from the laboratory experiments in addition to analyses of water samples from 7 coastal rivers in Victoria, Australia, showed consistent positive (Sr:Ca) and negative (Ba:Ca) non-linear relationships between salinity and otolith/water chemistry, with the greatest change in elemental concentrations occurring at <5%. Otolith Sr:Ca increased linearly with ambient values, while otolith Ba:Ca increased exponentially. Uptake of Sr and Ba into the otoliths varied with salinity, with partition coefficients (DSr and DBa) maximised at the lowest and highest salinities, respectively. Otolith transects revealed high individual variability in the timing and magnitude of Sr:Ca and Ba:Ca responses following transfer of bass from higher salinities to the lowest salinity (0.5%). Substantial time-lags in elemental uptake were also evident, with Sr:Ca taking ≤40 d and Ba:Ca =30 d for concentrations to reach equilibrium at 0.5%. Whilst otolith Sr:Ca and Ba:Ca are clearly useful as indicators of movement across coarse salinity gradients, our data suggest that the addition of alternative chemical markers to augment measurement of trace element concentrations is needed to improve resolution at finer scales. © Inter-Research 2010. Source

Heard G.W.,La Trobe University | Scroggie M.P.,Arthur Rylah Institute for Environmental Research | Malone B.S.,La Trobe University
Biological Conservation

Classical metapopulation theory (CMT) has proven an attractive paradigm for ecologists concerned with the conservation of aquatic-breeding amphibians, given its apparent fit with the population dynamics of these animals, and the opportunities the concept provides to assess alternate management options. Nevertheless, several authors have cautioned against uncritical application of this paradigm. We assessed the application of CMT to the conservation of the endangered growling grass frog (. Litoria raniformis) in the urbanising landscapes of Melbourne, Victoria, Australia. Support for five predictions developed from the basic tenets of CMT was assessed using a multi-year occupancy and mark-recapture data-set. There was congruence between all five predictions and data. Wetland occupancy was strongly influenced by the proximity of neighbouring populations ('connectivity'), but the estimated rate of dispersal between wetlands was low. Wetland occupancy was also temporally dynamic, with only a weak effect of connectivity on the probability of extinction, but a strong positive influence of connectivity on the probability of colonisation. Our work confirms that CMT provides a useful model of the dynamics of . L. raniformis in urbanising landscapes, and justifies the application of the paradigm to conservation planning for this species. We argue that CMT may prove relevant to numerous aquatic-breeding amphibians, and encourage assessment of the application of CMT to the conservation of these animals. © 2012 Elsevier Ltd. Source

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