Suchergebnisse

Contents -- Preface -- Prologue -- 1. Ausmerica -- 2. Enter the Naked Ape -- 3. Remorse -- 4. Biowealth -- 5. Liquidated Assets -- 6. Sick Planet, Sick People -- 7. The Bomb Is Still Ticking -- 8. Ignorance and Greed -- 9. Theocracy -- 10. Circling the Drain -- 11. Save This House -- Acknowledgments -- Notes

It is unequivocal that the poor condition of South Australia's terrestrial biodiversity is continuing to decline overall – much like elsewhere in Australia. This decline is mainly due to the legacy of vegetation clearing and habitat modification since European colonisation, the destructive influence of invasive species (especially predators like cats and foxes) on its native fauna and flora, and impotent or broken legislation to prevent further damage. The struggle to maintain our remaining biodiversity, and our intentions to restore once-healthy ecosystems, are rendered even more difficult by the added influence of rapid climate disruption. Despite the pessimistic outlook, South Australians have successfully employed several effective conservation mechanisms, including increasing the coverage of our network of protected areas, doing ecological restoration projects, reducing the densities of feral animals across landscapes, encouraging private landholders to protect their biodiversity assets, releasing environmental water flows to rivers and wetlands, and bringing more people in touch with nature. While these strategies are certainly stepping in the right direction, our policies and conservation targets have been hampered by arbitrary baselines, a lack of cohesion among projects and associated legislation, unrepresentative protected areas, and inappropriate spatial and time scales of intervention. While the challenges are many, there are several tractable and affordable actions that can be taken immediately to improve the prospect of the State's biodiversity into the near future. These include coordinating existing and promoting broader-scale ecological restoration projects, establishing strategic and evidence-based control of invasive species, planning more representative protected-area networks that are managed effectively for conservation outcomes, fixing broken environmental legislation, avoiding or severely limiting biodiversity-offset incentives, expanding conservation covenants on private land, ...

AbstractAustralia's high per capita emissions rates makes it is a major emitter of anthropogenic greenhouse gases, but its low intrinsic growth rate means that future increases in population size will be dictated by net overseas immigration. We constructed matrix models and projected the population to 2100 under six different immigration scenarios. A constant 1 per cent proportional immigration scenario would result in 53 million people by 2100, producing 30.7 Gt CO2‐e over that interval. Zero net immigration would achieve approximate population stability by mid‐century and produce 24.1 Gt CO2‐e. Achieving a 27 per cent reduction in annual emissions by 2030 would require a 1.5‐ to 2.0‐fold reduction in per‐capita emissions; an 80 per cent reduction by 2050 would require a 5.8‐ to 10.2‐fold reduction. Australia's capacity to limit its future emissions will therefore depend primarily on a massive technological transformation of its energy sector, but business‐as‐usual immigration rates will make achieving meaningful mid‐century targets more difficult.

This study examined the dive behaviour of 20 lactating New Zealand fur seals
(Arctocephalus forsteri) breeding at Fuchsia Gully
(Ohinepuha, 45˚52S, 170˚44E), Otago Peninsula, New Zealand, over
five consecutive austral summers (1993/94–1997/98). We examined
annual variation in dive behaviour by classifying series of dives into dive
bouts using an iterative statistical technique. We found a non-random pattern
of dive bouts and bout classification was relatively insensitive to changes in
the clustering parameters used. Minimum bouts consisted of at least three
dives 10 m occurring within a 20-min period. Bouts were classified into three
bout types (clusters) using a multi-variate clustering procedure. These
clusters described bouts of: (1) long duration with many dives of medium depth
(LONG); (2) short duration with few, shallow dives (SHALLOW); and (3) short
duration consisting of long, deep dives and long surface intervals and bottom
times (DEEP). Diving was primarily nocturnal, and bout type varied
significantly with time of day. The proportion of LONG bouts was greatest at
dusk and least near dawn, SHALLOW bouts predominated during the night, and
DEEP bouts were of importance near dawn. Few dives occurred during the day. We
detected no annual differences in individual parameters of dive behaviour due
to low statistical power. We used randomisation tests to assess whether the
proportion of each bout type might vary in years of differing prey
consumption, but no significant differences were found. Changes in prey
composition were detected in two of these years, which suggests that using the
dive behaviour of generalist predators to detect changes in resource
availability may be a poor option. The high degree of flexibility in foraging
behaviour of the New Zealand fur seal means that, inevitably, analyses of dive
behaviour will have low statistical power. Changes in foraging behaviour may
only be useful to detect very large changes in resource availability.
Alternatively, very large sample sizes may be able to detect more subtle
changes.

This is an Open Access article, distributed under the terms of the Creative Commons Attribution licence (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted re-use, distribution, and reproduction in any medium, provided the original work is properly cited. ; The number of shark-human interactions and shark bites per capita has been increasing since the 1980s, leading to a rise in measures developed to mitigate the risk of shark bites. Yet many of the products commercially available for personal protection have not been scientifically tested, potentially providing an exaggerated sense of security to the people using them. We tested five personal shark deterrents developed for surfers (Shark Shield Pty Ltd [Ocean Guardian] Freedom+ Surf, Rpela, SharkBanz bracelet, SharkBanz surf leash, and Chillax Wax) by comparing the percentage of baits taken, distance to the bait, number of passes, and whether a shark reaction could be observed. We did a total of 297 successful trials at the Neptune Islands Group Marine Park in South Australia, during which 44 different white sharks (Carcharodon carcharias) interacted with the bait, making a total of 1413 passes. The effectiveness of the deterrents was variable, with the Freedom+ Surf affecting shark behaviour the most and reducing the percentage of bait taken from 96% (relative to the control board) to 40%. The mean distance of sharks to the board increased from 1.6 ± 0.1 m (control board) to 2.6 ± 0.1 m when the Freedom Surf+ was active. The other deterrents had limited or no measurable effect on white shark behaviour. Based on our power analyses, the smallest effect size that could be reliably detected was ∼15%, which for the first time provides information about the effect size that a deterrent study like ours can reliably detect. Our study shows that deterrents based on similar principles—overwhelming a shark's electroreceptors (the ampullae of Lorenzini) with electrical pulses—differ in their efficacy, reinforcing the need to test each product independently. Our results will allow private and government agencies and the public to make informed decisions about the use and suitability of these five products. ; The following grant information was disclosed by the authors: New South Wales Department of Primary Industries Shark Management Strategy (SMS) Competitive Annual Grants Program. Government of South Australia. Ocean Guardian Pty Ltd. Neiser Foundation.

Non-indigenous animal species threaten biodiversity and ecosystem stability by damaging or transforming habitats, killing or out-competing native species and spreading disease. We use World Heritage Area Kakadu National Park, northern Australia, as a focal region to illustrate the current and potential threats posed by non-indigenous animal species to internationally and nationally recognised natural and cultural values. Available evidence suggests that large feral herbivores such as Asian swamp buffalo, pigs and horses are the most ecologically threatening species in this region. This may reflect the inherent research bias, because these species are highly visible and impact primary production; consequently, their control has attracted the strongest research and management efforts. Burgeoning threats, such as the already established cane toad and crazy ant, and potentially non-indigenous freshwater fish, marine invertebrates and pathogens, may cause severe problems for native biodiversity. To counter these threats, management agencies must apply an ongoing, planned and practical approach using scientifically based and well funded control measures; however, many stakeholders require direct evidence of the damage caused by non-indigenous species before agreeing to implement control. To demonstrate the increasing priority of non-indigenous species research in Australia and to quantify taxonomic and habitat biases in research focus, we compiled an extensive biography of peer-reviewed articles published between 1950 and 2005. Approximately 1000 scientific papers have been published on the impact and control of exotic animals in Australia, with a strong bias towards terrestrial systems and mammals. Despite the sheer quantity of research on non-indigenous species and their effects, management responses remain largely ad hoc and poorly evaluated, especially in northern Australia and in high-value areas such as Kakadu National Park. We argue that improved management in relatively isolated and susceptible tropical regions requires (1) robust quantification of density–damage relationships, and (2) the delivery of research findings that stimulate land managers to develop cost-effective control and monitoring programs.

Context Some large herbivores introduced to Australia have achieved population densities so high as to cause considerable ecological damage. Intriguingly, others have been relatively less successful and have correspondingly perturbed their new environments less. An excellent example is two similar-sized bovine species that established feral populations in the Northern Territory of Australia in the mid-19th century. Asian swamp buffalo (Bubalus bubalis) rapidly colonised the tropical savannas, causing ecological degradation, especially on freshwater swamps. In contrast, banteng (Bos javanicus) are restricted to their point of introduction and have caused relatively negligible ecological damage. Understanding the reasons of this differential success is of theoretical and applied interest and contributes to managing large herbivore populations for ex situ conservation and feral-animal control. Aims To compare the population structure of buffalo and banteng on the basis of shot samples, so as to construct life tables for four contemporary (low-density) buffalo populations, and collated data from previous work from three historical (high-density) buffalo populations and one banteng population (the only extant ex situ population in existence). Further, to provide a validation of age estimation with and without informed priors in a Bayesian model comparing horn length and ages estimated from tooth cementum annuli. Finally, to interpret our results in the context of relative invasion potential of the two bovid species. Key Results For both species, survival of juveniles was the most important demographic component influencing deterministic population growth. However, buffalo have the demographic capacity to recover swiftly after control because of high survival and fertility rates across a range of population densities. Fertility of buffalo was historically greater than that of banteng, and buffalo fertility increased as their populations were reduced. Conclusions These findings highlight how subtle differences in demographic rates and feeding ecology can influence the success (high population growth and range expansion) of large herbivores, knowledge which is increasingly important for managing invasive species effectively. Implications We show that that individual life-history traits and demographic performance, especially fertility, play an important role in determining the spread of invasive bovids in a novel environment.

Hot-iron brands were used to mark permanently 14 000 six-week-old southern elephant seal (Mirounga leonina L.) pups at Macquarie Island between 1993 and 2000. We assessed temporal changes in the quality of 4932 brands applied in 1998 and 1999 to determine the duration of the brand wound, and the relationships between brand healing, brand readability and the amount of skin and hair damage peripheral to the brand characters. Most (98%) brand wounds were healed within one year. Brand-mark healing, peripheral skin damage and brand readability were significantly (P < 0.05) correlated. The proportion of healed and readable brands increased in the population during the first annual moult, and thereafter these proportions remained high (>95%) for the marked population. The mean number of brand characters with peripheral skin damage decreased significantly over the same period. The seal's annual hair and skin moult is the process that contributed most to the healing of brand wounds. We also assessed our branding technique to determine whether any of the features we measured contributed to a poor-quality brand. Excessive pressure used during brand-iron application is the most probable cause of unsightly peripheral skin damage, but this damage is short lived.

The legacy of deliberate and accidental introductions of invasive alien species to Australia has had a hefty economic toll, yet quantifying the magnitude of the costs associated with direct loss and damage, as well as for management interventions, remains elusive. This is because the reliability of cost estimates and under-sampling have not been determined. We provide the first detailed analysis of the reported costs associated with invasive species to the Australian economy since the 1960s, based on the recently published InvaCost database and supplementary information, for a total of 2078 unique cost entries. Since the 1960s, Australia has spent or incurred losses totalling at least US$298.58 billion (2017 value) or AU$389.59 billion (2017 average exchange rate) from invasive species. However, this is an underestimate given that costs rise as the number of estimates increases following a power law. There was an average 1.8–6.3-fold increase in the total costs per decade since the 1970s to the present, producing estimated costs of US$6.09–57.91 billion year-1 (all costs combined) or US$225.31 million–6.84 billion year-1 (observed, highly reliable costs only). Costs arising from plant species were the highest among kingdoms (US$151.68 billion), although most of the costs were not attributable to single species. Of the identified weedy species, the costliest were annual ryegrass (Lolium rigidum), parthenium (Parthenium hysterophorus) and ragwort (Senecio jacobaea). The four costliest classes were mammals (US$48.63 billion), insects (US$11.95 billion), eudicots (US$4.10 billion) and monocots (US$1.92 billion). The three costliest species were all animals – cats (Felis catus), rabbits (Oryctolagus cuniculus) and red imported fire ants (Solenopsis invicta). Each State/Territory had a different suite of major costs by species, but with most (3–62%) costs derived from one to three species per political unit. Most (61%) of the reported costs applied to multiple environments and 73% of the total pertained to direct damage or loss compared to management costs only, with both of these findings reflecting the availability of data. Rising incursions of invasive species will continue to have substantial costs for the Australian economy, but with better investment, standardised assessments and reporting and coordinated interventions (including eradications), some of these costs could be substantially reduced.

The legacy of deliberate and accidental introductions of invasive alien species to Australia has had a hefty economic toll, yet quantifying the magnitude of the costs associated with direct loss and damage, as well as for management interventions, remains elusive. This is because the reliability of cost estimates and under-sampling have not been determined. We provide the first detailed analysis of the reported costs associated with invasive species to the Australian economy since the 1960s, based on the recently published InvaCost database and supplementary information, for a total of 2078 unique cost entries. Since the 1960s, Australia has spent or incurred losses totalling at least US$298.58 billion (2017 value) or AU$389.59 billion (2017 average exchange rate) from invasive species. However, this is an underestimate given that costs rise as the number of estimates increases following a power law. There was an average 1.8–6.3-fold increase in the total costs per decade since the 1970s to the present, producing estimated costs of US$6.09–57.91 billion year-1 (all costs combined) or US$225.31 million–6.84 billion year-1 (observed, highly reliable costs only). Costs arising from plant species were the highest among kingdoms (US$151.68 billion), although most of the costs were not attributable to single species. Of the identified weedy species, the costliest were annual ryegrass (Lolium rigidum), parthenium (Parthenium hysterophorus) and ragwort (Senecio jacobaea). The four costliest classes were mammals (US$48.63 billion), insects (US$11.95 billion), eudicots (US$4.10 billion) and monocots (US$1.92 billion). The three costliest species were all animals – cats (Felis catus), rabbits (Oryctolagus cuniculus) and red imported fire ants (Solenopsis invicta). Each State/Territory had a different suite of major costs by species, but with most (3–62%) costs derived from one to three species per political unit. Most (61%) of the reported costs applied to multiple environments and 73% of the total pertained to direct ...

The legacy of deliberate and accidental introductions of invasive alien species to Australia has had a hefty economic toll, yet quantifying the magnitude of the costs associated with direct loss and damage, as well as for management interventions, remains elusive. This is because the reliability of cost estimates and under-sampling have not been determined. We provide the first detailed analysis of the reported costs associated with invasive species to the Australian economy since the 1960s, based on the recently published InvaCost database and supplementary information, for a total of 2078 unique cost entries. Since the 1960s, Australia has spent or incurred losses totalling at least US$298.58 billion (2017 value) or AU$389.59 billion (2017 average exchange rate) from invasive species. However, this is an underestimate given that costs rise as the number of estimates increases following a power law. There was an average 1.8–6.3-fold increase in the total costs per decade since the 1970s to the present, producing estimated costs of US$6.09–57.91 billion year-1 (all costs combined) or US$225.31 million–6.84 billion year-1 (observed, highly reliable costs only). Costs arising from plant species were the highest among kingdoms (US$151.68 billion), although most of the costs were not attributable to single species. Of the identified weedy species, the costliest were annual ryegrass (Lolium rigidum), parthenium (Parthenium hysterophorus) and ragwort (Senecio jacobaea). The four costliest classes were mammals (US$48.63 billion), insects (US$11.95 billion), eudicots (US$4.10 billion) and monocots (US$1.92 billion). The three costliest species were all animals – cats (Felis catus), rabbits (Oryctolagus cuniculus) and red imported fire ants (Solenopsis invicta). Each State/Territory had a different suite of major costs by species, but with most (3–62%) costs derived from one to three species per political unit. Most (61%) of the reported costs applied to multiple environments and 73% of the total pertained to direct damage or loss compared to management costs only, with both of these findings reflecting the availability of data. Rising incursions of invasive species will continue to have substantial costs for the Australian economy, but with better investment, standardised assessments and reporting and coordinated interventions (including eradications), some of these costs could be substantially reduced.