Isolation of Pseudomonas pseudomallei from clay layers at defined depths

Twelve strains of Pseudomonas pseudomallei were isolated from the soil and water of a sheep paddock over a two-year period. The organism was recovered from the clay layer of the soil profile as well as from water that seeps into this layer during the "wet" season. Five isolates were obtained before the commencement of the "wet" season; environmental factors appear to play an important role in the survival of Ps. pseudomallei during the "dry" season. Lower isolation rates were recorded than those indicated by workers in southeast Asia and Iran.

Quantifying the effects of climate change and water abstraction on a population of barramundi (Lates calcarifer), a diadromous estuarine finfish

Many aquatic species are linked to environmental drivers such as temperature and salinity through processes such as spawning, recruitment and growth. Information is needed on how fished species may respond to altered environmental drivers under climate change so that adaptive management strategies can be developed. Barramundi (Lates calcarifer) is a highly prized species of the Indo-West Pacific, whose recruitment and growth is driven by river discharge. We developed a monthly age- and length-structured population model for barramundi. Monte Carlo Markov Chain simulations were used to explore the population's response to altered river discharges under modelled total licenced water abstraction and projected climate change, derived and downscaled from Global Climate Model A1FI. Mean values of exploitable biomass, annual catch, maximum sustainable yield and spawning stock size were significantly reduced under scenarios where river discharge was reduced; despite including uncertainty. These results suggest that the upstream use of water resources and climate change have potential to significantly reduce downstream barramundi stock sizes and harvests and may undermine the inherent resilience of estuarine-dependent fisheries. © 2012 CSIRO.