A review of the biology, ecology, distribution and control of Mozambique tilapia, Oreochromis mossambicus (Peters 1852) (Pisces: Cichlidae) with particular emphasis on invasive Australian populations

Oreochromis mossambicus (Peters 1852) are native to the eastward flowing rivers of central and southern Africa but from the early 1930s they have been widely distributed around the world for aquaculture and for biological control of weeds and insects. While O. mossambicus are now not commonly used as an aquaculture species, the biological traits that made them a popular culture species including tolerance to wide ranging ecological conditions, generalist dietary requirements and rapid reproduction with maternal care have also made them a 'model' invader. Self-sustaining populations now exist in almost every region to which they have been imported. In Australia, since their introduction in the 1970s, O. mossambicus have become established in catchments along the east and west coasts and have the potential to colonise other adjacent drainages. It is thought that intentional translocations are likely to be the most significant factor in their spread in Australia. The ecological and physical tolerances and preferences, reproductive behaviour, hybridization and the high degree of plasticity in the life history traits of O. mossambicus are reviewed. Impacts of O. mossambicus on natural ecosystems including competitive displacement of native species, habitat alteration, predation and as a vector in the spread of diseases are discussed. Potential methods for eradicating or controlling invasive populations of O. mossambicus including physical removal, piscicides, screens, environmental management and genetic technologies are outlined.

Assessing the potential of the rust fungus Puccinia spegazzinii as a classical biological control agent for the invasive weed Mikania micrantha in Papua New Guinea

The rust fungus Puccinia spegazzinii was introduced into Papua New Guinea (PNG) in 2008 as a classical biological control agent of the invasive weed Mikania micrantha (Asteraceae), following its earlier release in India, mainland China and Taiwan. Prior to implementing field releases in PNG, assessments were conducted to determine the most suitable rust pathotype for the country, potential for damage to non-target species, most efficient culturing method and potential impact to M. micrantha. The pathotype from eastern Ecuador was selected from the seven pathotypes tested, since all the plant populations evaluated from PNG were highly susceptible to it. None of the 11 plant species (representing eight families) tested to confirm host specificity showed symptoms of infection, supporting previous host range determination. A method of mass-producing inoculum of the rust fungus, using a simple technology which can be readily replicated in other countries, was developed. Comparative growth trials over one rust generation showed that M. micrantha plants infected with the rust generally had both lower growth rates and lower final dry weights, and produced fewer nodes than uninfected plants. There were significant correlations between the number of pustules and (a) the growth rate, (b) number of new nodes and (c) final total dry weight of single-stemmed plants placed in open sunlight and between the number of pustules and number of new nodes of multi-stemmed plants placed under cocoa trees. The trials suggest that field densities of M. micrantha could be reduced if the rust populations are sufficiently high. Crown Copyright (C) 2013 Published by Elsevier Inc. All rights reserved.

Australia's newest quarantine for biological control

The paper describes the QC3 quarantine facility and supporting infrastructure which were purpose built for weed biological control at the Ecosciences Precinct. The quarantine is one of two new weed quarantine facilities in Australia and will service northern Australia. An account of the sharing philosophy between CSIRO and the Queensland Government and the necessity of working very closely with architects, project managers, builders and quarantine personnel is also given. This philosophy contributed to certification of the facility without any undue delays.

Cucumber volatile blend, a promising female-biased lure for Bactrocera cucumis (French 1907) (Diptera: Tephritidae: Dacinae), a pest fruit fly that does not respond to male attractants

Bactrocera cucumis (French 1907), the ‘cucumber fruit fly’, is a horticultural pest in Australia that primarily infests cucurbits and has also been recorded from tomatoes, papaw and several other hosts. It does not respond to known male lures, cue-lure and methyl eugenol, making monitoring and control difficult. A cucumber volatile blend lure was recently developed in Hawaii and found to be an effective female-biased attractant for the melon fly B. cucurbitae. This lure was field tested in north Queensland, Australia in McPhail traps in comparison with orange ammonia, Cera Trap® and a control, and was found to more consistently trap B. cucumis than the other lures. B. cucumis were caught at 41% of the cucumber volatile lure trap clearances, compared with 27% of the orange ammonia, 18% of the Cera Trap and 16% of the control trap clearances. The cucumber volatile lure was more attractive to B. cucumis in low population densities and also trapped B. cucumis earlier on average than the other lures. Data analysed from the site with highest trap catches (Spring Creek) showed that the cucumber volatile lure caught significantly more B. cucumis than the other traps in four of the 11 trap clearance periods, and for the remaining clearances, no other trap type caught significantly more flies than the cucumber volatile lure. The cucumber volatile lure had a strong female-biased attraction but it was not significantly more female-biased than orange ammonia or Cera Trap. Cucumber volatile lure traps were cleaner to service resulting in better quality specimens than the orange ammonia trap or Cera Trap. These findings have potential implications for market access monitoring for determining pest freedom, and for biosecurity monitoring programmes in other countries that wish to detect B. cucumis early.

Ecology, Behaviour and Control of Apis cerana with a Focus on Relevance to the Australian Incursion

Apis cerana Fabricius is endemic to most of Asia, where it has been used for honey production and pollination services for thousands of years. Since the 1980s, A. cerana has been introduced to areas outside its natural range (namely New Guinea, the Solomon Islands, and Australia), which sparked fears that it may become a pest species that could compete with, and negatively affect, native Australian fauna and flora, as well as commercially kept A. mellifera and commercial crops. This literature review is a response to these concerns and reviews what is known about the ecology and behaviour of A. cerana. Differences between temperate and tropical strains of A. cerana are reviewed, as are A. cerana pollination, competition between A. cerana and A. mellifera, and the impact and control strategies of introduced A. cerana, with a particular focus on gaps of current knowledge.

Predictive modelling to aid the regional-scale management of a vertebrate pest

Extensive resources are allocated to managing vertebrate pests, yet spatial understanding of pest threats, and how they respond to management, is limited at the regional scale where much decision-making is undertaken. We provide regional-scale spatial models and management guidance for European rabbits (Oryctolagus cuniculus) in a 260,791 km(2) region in Australia by determining habitat suitability, habitat susceptibility and the effects of the primary rabbit management options (barrier fence, shooting and baiting and warren ripping) or changing predation or disease control levels. A participatory modelling approach was used to develop a Bayesian network which captured the main drivers of suitability and spread, which in turn was linked spatially to develop high resolution risk maps. Policy-makers, rabbit managers and technical experts were responsible for defining the questions the model needed to address, and for subsequently developing and parameterising the model. Habitat suitability was determined by conditions required for warren-building and by above-ground requirements, such as food and harbour, and habitat susceptibility by the distance from current distributions, habitat suitability, and the costs of traversing habitats of different quality. At least one-third of the region had a high probability of being highly suitable (support high rabbit densities), with the model supported by validation. Habitat susceptibility was largely restricted by the current known rabbit distribution. Warren ripping was the most effective control option as warrens were considered essential for rabbit persistence. The anticipated increase in disease resistance was predicted to increase the probability of moderately suitable habitat becoming highly suitable, but not increase the at-risk area. We demonstrate that it is possible to build spatial models to guide regional-level management of vertebrate pests which use the best available knowledge and capture fine spatial-scale processes.

Australia’s present scientific capacity to progress the biological control of weeds

Australia has a very proud record of achievement in biological control of weeds and the underpinning science. From the earliest campaigns against prickly pear and lantana, weed biocontrol developed with major contributions from CSIRO and state governments to produce outstanding successes against weeds such as salvinia, rubber vine, Noogoora burr, bridal creeper and prickly pear. Maximum research activity occurred in the 1980s when some 30 scientists were working world wide on Australia’s weed problems. Activity declined gradually until the last few years when government divestment in agricultural research greatly diminished capacity. There are now approximately eight full-time scientist equivalents supporting Australia’s weed biocontrol effort. Australia may now need to adopt a team approach to tackle future major weed biological control projects.

Life cycle and host range of Phycitasp. rejected for biological control of prickly acacia in Australia

Prickly acacia (Vachellia nilotica subsp. indica), a native of the Indian subcontinent, is a serious weed of the grazing areas of northern Australia and is a target for classical biological control. Native range surveys in India identified a leaf webber, Phycita sp. (Lepidoptera: Pyralidae) as a prospective biological control agent for prickly acacia. In this study, we report the life cycle and host-specificity test results Phycita sp. and highlight the contradictory results between the no-choice tests in India and Australia and the field host range in India. In no-choice tests in India and Australia, Phycita sp. completed development on two of 11 and 16 of 27 non-target test plant species, respectively. Although Phycita sp. fed and completed development on two non-target test plant species (Vachellia planifrons and V. leucophloea) in no-choice tests in India, there was no evidence of the insect on the two non-target test plant species in the field. Our contention is that oviposition behaviour could be the key mechanism in host selection of Phycita sp., resulting in its incidence only on prickly acacia in India. This is supported by paired oviposition choice tests involving three test plant species (Acacia baileyana, A. mearnsii and A. deanei) in quarantine in Australia, where eggs were laid only on prickly acacia. However, in paired oviposition choice trials, only few eggs were laid, making the results unreliable. Although oviposition choice tests suggest that prickly acacia is the most preferred and natural host, difficulties in conducting choice oviposition tests with fully grown trees under quarantine conditions in Australia and the logistic difficulties of conducting open-field tests with fully grown native Australian plants in India have led to rejection of Phycita sp. as a potential biological control agent for prickly acacia in Australia.