Furlan E.,University of Melbourne |
Griffiths J.,CESAR Consultants |
Griffiths J.,Australian Department of Primary Industries and Fisheries |
Gust N.,Australian Department of Primary Industries and Fisheries |
And 6 more authors.
Australian Journal of Zoology | Year: 2011
The body size of the platypus (Ornithorhynchus anatinus) is known to vary across both its latitudinal range and relatively short geographic distances. Here we consider how variation in platypus length and weight associates with environmental variables throughout the species' range. Based on data from over 800 individuals, a Bergmann's cline (increased body size in regions of lower temperature) was detected across the species latitudinal range. The opposite association, however, was present at smaller scales when comparing platypus body size and temperature within southern mainland Australia, or within an individual river basin. Temperature regimes alone clearly did not dictate body size in platypuses, although disentangling the effects of different climatic variables on body size variation was difficult because of correlations amongst variables. Nevertheless, within suitable platypus habitat in south-eastern Australia, areas of relatively lower rainfall and higher temperatures were typically associated with larger-bodied platypuses. The potential benefits to larger-bodied animals living under these conditions are explored, including consideration of variation in energy expenditure and food availability. Assuming these associations with environmental variables are biologically significant, a shift in platypus body size is anticipated in the future with predicted changes in climate. © 2011 CSIRO.
Mccoll S.A.,CESAR Consultants |
Khan M.,Agri Science Queensland |
Umina P.A.,CESAR Consultants |
Umina P.A.,University of Melbourne
Australian Journal of Entomology | Year: 2011
Here we review the current knowledge of green mirids, Creontiades dilutus (Hemiptera: Miridae). Creontiades dilutus are highly polyphagous pests that are endemic to Australia. They are widely distributed across Australia and feed on a broad range of agricultural crops. Recently, C. dilutus has become an important focus of pest control in Australian cotton crops, most likely due to a decrease in insecticide use associated with the widespread uptake of transgenic cotton varieties. Prior to this, C. dilutus had been coincidentally controlled in cotton by applications of insecticides targeted at other pests such as Helicoverpa spp. Further, the pest status of C. dilutus in summer pulse crops has become more apparent due to the increased research dedicated to this area over the past decade. We review various aspects of the biology and ecology of C. dilutus, including their life cycle, feeding behaviour and host plants. We also examine current control methods and laboratory-rearing techniques, which will be important for the development of novel control strategies in cotton and other cropping environments. Possible future research directions are highlighted, such as dispersal capabilities and extent of genetic structure within C. dilutus populations, as these will have important implications for effective and sustainable control in the future. © 2010 The Authors. Journal compilation © 2010 Australian Entomological Society.
Umina P.A.,University of Melbourne |
Arthur A.L.,University of Melbourne |
McColl S.A.,CESAR Consultants |
Hoffmann A.A.,University of Melbourne |
Roberts J.M.K.,University of Melbourne
Crop Protection | Year: 2010
Control of invertebrate pests in broad-acre agriculture largely relies on the application of broad-spectrum pesticides, however resistance problems and environmental concerns are driving a search for alternatives including more selective products. Here we explore the feasibility of using novel chemical groupings in the control of problematic pests that attack germinating pastures and grain crops in Australia. A modified laboratory bioassay is described for testing the response of several invertebrate pests to pesticides that have contact and systemic/translaminar properties. Two contact pesticides (fenitrothion and gamma-cyhalothrin) and three pesticides with strong systemic/translaminar properties (lambda-cyhalothrin, abamectin and diafenthiuron) showed promise for control of the collembolan Sminthurus viridis and four mite pests (Halotydeus destructor, Balaustium medicagoense, Penthaleus falcatus and Bryobia sp.). No single pesticide emerged as the most efficacious against all these pests, highlighting the need for correct pest identification before making control recommendations. Incorporating these new chemical options into pest control programs may help to control emerging pests and counter pesticide resistance issues. Selective pesticides in particular are likely to be compatible with integrated control programs that promote the establishment and maintenance of beneficial natural enemies. © 2009 Elsevier Ltd. All rights reserved.