Limited population structure, genetic drift and bottlenecks characterise an endangered bird species in a dynamic, fire-prone ecosystem

Fire is a major disturbance process in many ecosystems world-wide, resulting in spatially and temporally dynamic landscapes. For populations occupying such environments, fire-induced landscape change is likely to influence population processes, and genetic patterns and structure among populations. The Mallee Emu-wren Stipiturus mallee is an endangered passerine whose global distribution is confined to fire-prone, semi-arid mallee shrublands in south-eastern Australia. This species, with poor capacity for dispersal, has undergone a precipitous reduction in distribution and numbers in recent decades. We used genetic analyses of 11 length-variable, nuclear loci to examine population structure and processes within this species, across its global range. Populations of the Mallee Emu-wren exhibited a low to moderate level of genetic diversity, and evidence of bottlenecks and genetic drift. Bayesian clustering methods revealed weak genetic population structure across the species\u27 range. The direct effects of large fires, together with associated changes in the spatial and temporal patterns of suitable habitat, have the potential to cause population bottlenecks, serial local extinctions and subsequent recolonisation, all of which may interact to erode and homogenise genetic diversity in this species. Movement among temporally and spatially shifting habitat, appears to maintain long-term genetic connectivity. A plausible explanation for the observed genetic patterns is that, following extensive fires, recolonisation exceeds in-situ survival as the primary driver of population recovery in this species. These findings suggest that dynamic, fire-dominated landscapes can drive genetic homogenisation of populations of species with low-mobility and specialised habitat that otherwise would be expected to show strongly structured populations. Such effects must be considered when formulating management actions to conserve species in fire-prone systems

A Unique Resource Mutualism between the Giant Bornean Pitcher Plant, Nepenthes rajah, and Members of a Small Mammal Community

The carnivorous pitcher plant genus Nepenthes grows in nutrient-deficient substrates and produce jug-shaped leaf organs (pitchers) that trap arthropods as a source of N and P. A number of Bornean Nepenthes demonstrate novel nutrient acquisition strategies. Notably, three giant montane species are engaged in a mutualistic association with the mountain treeshrew, Tupaia montana, in which the treeshrew defecates into the pitchers while visiting them to feed on nectar secretions on the pitchers' lids

Modelling tropical fire ant (Solenopsis Geminata) dynamics and detection to inform an eradication project

Invasive species threaten endangered species worldwide and substantial effort is focused on their control. Eradication projects require critical resource allocation decisions, as they affect both the likelihood of success and the overall cost. However, these complex decisions must often be made within data-poor environments. Here we develop a mathematical framework to assist in resource allocation for invasive species control projects and we apply it to the proposed eradication of the tropical fire ant (Solenopsis geminata) from the islands of Ashmore Reef in the Timor Sea. Our framework contains two models: a population model and a detection model. Our stochastic population model is used to predict ant abundance through time and allows us to estimate the probability of eradication. Using abundance predictions from the population model, we use the detection model to predict the probability of ant detection through time. These models inform key decisions throughout the project, which include deciding how many baiting events should take place, deciding whether to invest in detector dogs and setting surveillance effort to confirm eradication following control. We find that using a combination of insect growth regulator and toxins are required to achieve a high probability of eradication over 2\ua0years, and we find that using two detector dogs may be more cost-effective than the use of lure deployment, provided that they are used across the life of the project. Our analysis lays a foundation for making decisions about control and detection throughout the project and provides specific advice about resource allocation

What determines habitat quality for a declining woodland bird in a fragmented environment: the grey-crowned babbler pomatostomus temporalis in South-Eastern Australia?

No grant i

Zoo Basel Newsletter. 2013, Juli

Climate change alters the frequency and severity of extreme events, such as drought. Such events will be increasingly important in shaping communities as climate change intensifies. The ability of species to withstand extreme events (resistance) and to recover once adverse conditions abate (resilience) will determine their persistence. We estimated the resistance and resilience of bird species during and after a 13-year drought (the \u27Big Dry\u27) in floodplain forests in south-eastern Australia. We conducted bird surveys at the beginning and end of the Big Dry, and after the abrupt end to the drought (the \u27Big Wet\u27), to evaluate species-specific changes in reporting rates among the three periods. We assessed changes in bird-breeding activity before and after the Big Wet to estimate demographic resilience based on breeding. Between the start and the end of the Big Dry (1998 vs. 2009), 37 of 67 species declined substantially. Of those, only two had increased reporting rates after the Big Wet (2009 vs. 2013) that were equal to or larger than their declines, while three partially recovered. All other declining species showed low resilience: 25 showed no change in reporting rates and seven declined further. The number of breeding species and total breeding activity of all species declined after the Big Wet, and there was no change in the number of young produced. The Big Dry caused widespread declines in the floodplain avifauna. Despite the drought being broken by 2 years of well-above-average rainfall and subsequent near-average rainfall, most species showed low resilience and there was little indication that overall breeding had increased. The effects of drought appeared to be pervasive for much of the floodplain avifauna, regardless of species traits (species body mass, fecundity, mobility or diet). Ecosystems such as these are likely to require active management and restoration, including reinstatement of natural flooding regimes, to improve ecological condition, to enhance resistance and resilience to extreme climate events

Diet breadth of a critically endangered owl presents challenges for invasive rodent management: a conservation conundrum

Trophic interactions between threatened species complicate management. Similarly, interactions between threatened species and pest species present management challenges, given that pest control can lead to non-target impacts (e.g. trophic cascades or secondary poisoning). There are records of the critically endangered Norfolk Island Morepork Ninox novaeseelandiae undulata consuming both threatened songbirds and invasive rodents that are subject to management interventions. Nevertheless, the diet of the morepork remains largely unknown. We visually screened regurgitated pellets using a microscope, alongside environmental DNA (eDNA) screening of pellets and scats, to investigate the diet of the Norfolk Island Morepork. A total of 113 pellets and 19 scats were collected between October 2020 and June 2021. All moreporks screened with eDNA metabarcoding had consumed invasive rodents and at least one-third of samples contained rodents. The owls were also found to have consumed four of five endemic songbirds and possibly an endemic parrot, most of which are threatened. Environmental DNA metabarcoding detected more taxa overall, but visual screening identified a greater richness of Orthoptera and Coleoptera in the diet. The frequency with which the Norfolk Island Morepork consumed rodents presents a conundrum for conservation managers. Control of invasive rodents is considered essential to support threatened songbirds, yet this same action places the species at risk of secondary poisoning. Urgent investigations are needed to identify effective control methods for invasive rodents that are safe for non-target species

Options for reducing uncertainty in impact classification for alien species

Impact assessment is an important and cost-effective tool for assisting in the identification and prioritization of invasive alien species. With the number of alien and invasive alien species expected to increase, reliance on impact assessment tools for the identification of species that pose the greatest threats will continue to grow. Given the importance of such assessments for management and resource allocation, it is critical to understand the uncertainty involved and what effect this may have on the outcome. Using an uncertainty typology and insects as a model taxon, we identified and classified the causes and types of uncertainty when performing impact assessments on alien species. We assessed 100 alien insect species across two rounds of assessments with each species independently assessed by two assessors. Agreement between assessors was relatively low for all three impact classification components (mechanism, severity, and confidence) after the first round of assessments. For the second round, we revised guidelines and gave assessors access to each other’s assessments which improved agreement by between 20% and 30% for impact mechanism, severity, and confidence. Of the 12 potential reasons for assessment discrepancies identified a priori, 11 were found to occur. The most frequent causes (and types) of uncertainty (i.e., differences between assessment outcomes for the same species) were as follows: incomplete information searches (systematic error), unclear mechanism and/or extent of impact (subjective judgment due to a lack of knowledge), and limitations of the assessment framework (context dependence). In response to these findings, we identify actions that may reduce uncertainty in the impact assessment process, particularly for assessing speciose taxa with diverse life histories such as Insects. Evidence of environmental impact was available for most insect species, and (of the non-random original subset of species assessed) 14 of those with evidence were identified as high impact species (with either major or massive impact). Although uncertainty in risk assessment, including impact assessments, can never be eliminated, identifying, and communicating its cause and variety is a first step toward its reduction and a more reliable assessment outcome, regardless of the taxa being assessed

Crop Updates 2008 - Weeds

This session covers twenty nine papers from different authors: 1. BOXER® GOLD, a new pre-emergent herbicide option for WA wheat and barley growers for the control of Annual Ryegrass and Toad Rush, Craig A. Ruchs, Syngenta Crop Protection Australia Pty Ltd 2. Efficacy of Boxer Gold in the control of annual ryegrass in wheat, Dr Abul Hashem, Dr Catherine Borger, Department of Agriculture and Food, Mr Ken McKee, Field Development Manager, Syngenta Crop Protection Australia Pty Ltd 3. Alternative herbicides to avoid trifluralin resistance, Catherine Borger and Abul Hashem, Department of Agriculture and Food 4. Exiting new herbicides for ryegrass control in wheat, Peter Newman, Department of Agriculture and Food 5. Herbicide options for resistant wild radish in wheat, Peter Newman, Department of Agriculture and Food 6. A near-complete control of wild radish with three new herbicide products, Aik Cheam and Siew Lee, Department of Agriculture and Food 7. An investigation of diflufenican resistance mechanism/s in wild radish, Meagan Pearce, Dr Michael Walsh and Prof. Stephen Powles, Western Australian Herbicide Resistance Initiative, School of Plant Biology, University of WA 8. Synergistic effects of Group C and GroupF herbicides on resistant and susceptible wild radish populations, Kent Stone, Dr Michael Walsh and Prof. Stephen Powles, Western Australian Herbicide Resistance Initiative, School of Plant Biology, University of WA 9. Precept® for the management of wild radish resistant to PDS inhibiting herbicides, Mike Clarke and Andrew Loorham, Bayer Cropscience Pty Ltd, Dr Michael Walsh, WAHRI, University of Western Australia 10. Evolution of glyphosate resistance in annual ryegrass: Effects of cutting rates, Roberto Busi and Stephen B. Powles, Western Australian Herbicide Resistance Initiative, School of Plant Biology, The University of Western Australia 11. Metribuzin and other herbicides pre-sowing of lupins, Peter Newman, Department of Agriculture and Food 12. Crop topping lupins with glufosinate gives poor control of ryegrass seed set, Peter Newman, Department of Agriculture and Food 13. Brome grass has developed multiple resistance to Group B and C herbicides, Dr Abul Hashem, Dr Catherine Borger and Dr Shahab Pathan, Department of Agriculture and Food 14. Effect of sowing methods, Logran® and Metribuzin on weeds and wheat grain yield, Alexandra Douglas and Abul Hashem, Department of Agriculture and Food 15. Effect of alternative Group K herbicides on control of on-row annual ryegrass in wide row lupins, Dr Abul Hashem1, Ray Fulwood2 and Chris Roberts1, 1Department of Agriculture and Food, 2Farmer, Meckering, Western Australia 16. Control and seed production of annual ryegrass in wide row lupins within the Western Australian wheatbelt, Abul Hashem1,6, Alex Douglas1,6, Shahab Pathan1, Glen Riethmuller1,6 and 1,6Sally Peltzer, Department of Agriculture and Food, 6CRC Australian Weed Management 17. Effective weed control in wide row lupins, Glen Riethmuller, Abul Hashem and Shahab Pathan, Department of Agriculture and Food, and CRC Australian Weed Management 18. Slender iceplant control, Lorinda Hunt1, John Borger1, Meir Altman1,4 and Dr Ed Barrett-Lennard1,4, Department of Agriculture and Food, Western Australia1, University of Western Australia and Future Farm Industries CRC4 19. Chemical and non-chemical weed control – a European perspective, Glen Riethmuller, Department of Agriculture and Food 20. Mouldboard ploughing shows promise on sand, Peter Newman, Stephen Davies and Sally Peltzer, Department of Agriculture and Food 21. Weed seed head trimming, Glen Riethmuller and Abul Hashem, Department of Agriculture and Food 22. A survey of summer weed incidence and distribution across the WA wheatbelt, Pippa Michaela, Bill McLeodb, Catherine Borgerb and Alex Douglasb, aCurtin University of Technology, bDepartment of Agriculture and Food 23. Herbicide tolerance of field pea varieties, Harmohinder Dhammu and Mark Seymour, Department of Agriculture and Food 24. Herbicide tolerance of current/new wheat varieties, Dr Harmohinder Dhammu, Department of Agriculture and Food 25. Herbicide tolerance of new oat varieties, Harmohinder Dhammu, Vince Lambert and Chris Roberts, Department of Agriculture and Food 26. Herbicide tolerance of saltbush and bluebush, Lorinda Hunt1, John Borger1, Meir Altman1,4 and Dr Ed Barrett-Lennard1,4, Department of Agriculture and Food1, University of Western Australia and Future Farm Industries CRC4 27. A review of 2,4-D formulations and vapour drift, John H. Moore, Department of Agriculture and Food 28. Movement of 2,4-D butyl ester and the dose response of three formulations of 2,4-D on canola, John H. Moore, Department of Agriculture and Food 29. Pathways to registration – Improving pesticide research outcomes, Dr Rohan Rainbow, Manager Crop Protection, Grains Research and Development Corporatio

Prevention of infections and fever to improve outcome in older patients with acute stroke (PRECIOUS): a randomised, open, phase III, multifactorial, clinical trial with blinded outcome assessment

BackgroundInfections and fever after stroke are associated with poor functional outcome or death. We assessed whether prophylactic treatment with anti-emetic, antibiotic, or antipyretic medication would improve functional outcome in older patients with acute stroke. MethodsWe conducted an international, 2∗2∗2-factorial, randomised, controlled, open-label trial with blinded outcome assessment in patients aged 66 years or older with acute ischaemic stroke or intracerebral haemorrhage and a score on the National Institutes of Health Stroke Scale ≥ 6. Patients were randomly allocated (1:1) to metoclopramide (oral, rectal, or intravenous; 10 mg thrice daily) vs. no metoclopramide, ceftriaxone (intravenous; 2000 mg once daily) vs. no ceftriaxone, and paracetamol (oral, rectal, or intravenous; 1000 mg four times daily) vs. no paracetamol, started within 24 h after symptom onset and continued for four days. All participants received standard of care. The target sample size was 3800 patients. The primary outcome was the score on the modified Rankin Scale (mRS) at 90 days analysed with ordinal logistic regression and reported as an adjusted common odds ratio (an acOR 1 harm). This trial is registered (ISRCTN82217627). FindingsFrom April 2016 through June 2022, 1493 patients from 67 European sites were randomised to metoclopramide (n = 704) or no metoclopramide (n = 709), ceftriaxone (n = 594) or no ceftriaxone (n = 482), and paracetamol (n = 706) or no paracetamol (n = 739), of whom 1471 were included in the intention-to-treat analysis. Prophylactic use of study medication did not significantly alter the primary outcome at 90 days: metoclopramide vs. no metoclopramide (adjusted common odds ratio [acOR], 1.01; 95% CI 0.81–1.25), ceftriaxone vs. no ceftriaxone (acOR 0.99; 95% CI 0.77–1.27), paracetamol vs. no paracetamol (acOR 1.19; 95% CI 0.96–1.47). The study drugs were safe and not associated with an increased incidence of serious adverse events. InterpretationWe observed no sign of benefit of prophylactic use of metoclopramide, ceftriaxone, or paracetamol during four days in older patients with a moderately severe to severe acute stroke. FundingThis project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No: 634809

Deconstructing compassionate conservation

Compassionate conservation focuses on 4 tenets: first, do no harm; individuals matter; inclusivity of individual animals; and peaceful coexistence between humans and animals. Recently, compassionate conservation has been promoted as an alternative to conventional conservation philosophy. We believe examples presented by compassionate conservationists are deliberately or arbitrarily chosen to focus on mammals; inherently not compassionate; and offer ineffective conservation solutions. Compassionate conservation arbitrarily focuses on charismatic species, notably large predators and megaherbivores. The philosophy is not compassionate when it leaves invasive predators in the environment to cause harm to vastly more individuals of native species or uses the fear of harm by apex predators to terrorize mesopredators. Hindering the control of exotic species (megafauna, predators) in situ will not improve the conservation condition of the majority of biodiversity. The positions taken by so-called compassionate conservationists on particular species and on conservation actions could be extended to hinder other forms of conservation, including translocations, conservation fencing, and fertility control. Animal welfare is incredibly important to conservation, but ironically compassionate conservation does not offer the best welfare outcomes to animals and is often ineffective in achieving conservation goals. Consequently, compassionate conservation may threaten public and governmental support for conservation because of the limited understanding of conservation problems by the general public