Mozzies motivate microbats
While the humble mosquito is not welcome buzzing around and sharing viruses with humans, it has a valuable ecological role to play as a prey item for insectivorous bats, an ACU-led study has revealed.
Balancing the competing needs of environmental conservation and human health is critical, as urbanisation threatens wildlife, and their habitats and the very wildlife we are trying to protect may sometimes pose risks to our own health.
The multi-disciplinary team including Dr Leroy Gonsalves and Dr Vaughan Monamy (ACU), Dr Bradley Law (NSW Department of Primary Industries) and Dr Cameron Webb (University of Sydney and Westmead Hospital) has examined the role of mosquitoes as prey for bats as part of a broader project investigating potential indirect effects of mosquito control on the diet of small forest bats.
Findings of this study, Foraging Ranges of Insectivorous Bats Shift Relative to Changes in Mosquito Abundance, have just been published in the international journal, PLOS ONE.
The article presents the results of a radio tracking study in which the research team tracked the movements of a small (4 g) bat species (Vespadelus vulturnus, little forest bat) during two periods of contrasting extremes of mosquito abundance. Vespadelus vulturnus, a predator of mosquitoes, shifted from foraging in endangered coastal saltmarsh to endangered coastal swamp forest communities.
“The shift in foraging range of V. Vulturnus was relative to changes in abundance of mosquitoes (and no other prey) in these two habitats, highlighting the importance of mosquitoes as prey for this bat species,” lead researcher Dr Gonsalves said.
This study was the first in Australia to provide quantitative data about the importance of mosquitoes to the insectivorous bat diet by assessing whether foraging ranges of predators shift in relation to mosquito abundance and distribution. Important recommendations that may be applied to the management of pest and vector mosquito species while protecting local wildlife that use these as prey are also presented in the article.
Has bottled water lost its cool?
The bottled water fad may have finally dried up as Melbourne Fashion Week organisers banned plastic water bottles at this year’s event – replacing them with reusable aluminium bottles and refilling stations.
BPA, which has been in commercial use for making plastics since the 1950s, is getting a lot of bad press in toxicology and science circles. BPA is known to leach from plastic containers into their contents. Concerns were raised when the chemical was detected in the urine of 95 per cent of humans sampled in the US (including pregnant women), with higher levels in children.
BPA has been linked (in animal studies) to health problems including developmental and reproductive concerns, infertility, obesity, hypertension, diabetes, thyroid concerns and attention deficit disorder.
Breast and prostate cancer have also been reported in animal studies.
Opinions vary about the health risks of BPA. In some quarters, toxic effects in high-dose animal studies are not considered suitable for human-risk categorisation. ACU Professor of Toxicology Chris Winder said that action was ramping up to ban the chemical.
“Canada’s food regulator has banned its use, calling it a toxic chemical, and the US and EU are looking to reduce the level of BPA products being sold,” said Professor Winder.
“BPA is on its way out. The bad press is causing drink manufacturers to look for other plastics. Within 10 years most regulators will have taken steps to do something about it and within 20 years it will be gone.”
Tackling the complex issues of refugees
Rethinking Displacement: Asia Pacific Perspectives explores the interconnected factors that compel people to move within their homelands or traverse various borders. Bringing together historical and contemporary accounts, the book uses critical examinations to illustrate the commonalities in their lived experiences.
“Displacement is the scandal of the closing decades of the last century and the beginning of the new one,” said Ranabir Samaddar, Director, Mahanirban Calcutta Research Group.
“Human rights activists, humanitarian agencies, policy makers, development experts, and government planners are struggling to cope with the problem of displacement.”
“This collection of essays not only manages to fill the need, by bringing in the perspective of the new global order, it manages to tell us a different story of the Asian Century. Rethinking Displacement: Asia Pacific Perspectives is a must read for critical social scientists and developmental specialists of our time.”
Edited by Professor Ruchira Ganguly-Scrase, Professor of International Development Studies at ACU and Dr Kuntala Lahiri-Dutt,Fellow of the Resource Management in Asia Pacific program at The Australian National University, the book reiterates the ideas of sociologist Zigmund Bauman that displacement is the inherent story of modernity. Fr Frank Brennan SJ AO officially launched the book, and provided the audience with an insight into the nature of the book asa welcoming addition for its scrupulous academic concern in depicting the issues of displacement”.
“I am hopeful and confident that the wide range of issues addressed in the book will help the reader to come to understand the complexity of factors around refugees and develop more humane policies,” said Fr Brennan.
Investigating alcohol-related violence
In Australia, the impact of alcohol consumption is of growing concern, and the high economic cost and harms associated with alcohol-related violence receive continuing attention from both media and policy makers.
However, the longitudinal relationship between alcohol consumption and violence is unclear, with findings from prospective studies producing mixed results.
Lead Victorian researchers Professor Sheryl Hemphill and Dr Kirsty Balog, from ACU’s School of Psychology, are investigating the longitudinal relationships between alcohol consumption and violence among young Australians.
The current study used Victorian data from the International Youth Development Study to examine longitudinal relationships between alcohol consumption and severe interpersonal violence across the developmental periods of early adolescence to late adolescence emerging adulthood.
The International Youth Development Study began in 2002 and is a collaborative project between ACU, Deakin University, The University of Melbourne, and the University of Washington, USA.
Professor Hemphill said the study has found that alcohol use during early and mid adolescence can dredict violence two years later.
“A relationship between past year alcohol use and violence was found from Year 7 to Year 9 and Year 9 to Year 11. The results for links between heavy episodic drinking and violence were different, with some evidence for reciprocal relationships. However, for both measures of alcohol, some of these relationships no longer remained when covariates such as family conflict and affiliation with antisocial and drug-using friends were included in the models,” said Professor Hemphill.
“These findings suggest that risk processes begin in late childhood, or very early adolescence, so we need to target common risk factors for violence and alcohol at this time. For heavy episodic drinking and violence, given the reciprocal relationships, efforts to reduce one problem behaviour are likely to reduce the other.
“Further, the role that the social and family contexts have in influencing the relationships between alcohol use and interpersonal violence should be considered in further research to better inform preventive efforts.”