Biological control is widely utilised for the management of invasive alien plants (IAP). With the ever-increasing number of IAPs, it is important to prioritise targets for biocontrol in order to ...maximise the use of resources and the chances of success. This paper reviewed 12 previous systems developed to prioritise plant targets for biocontrol. The review underpins the selection of attributes and methodologies for the prioritisation of targets for biocontrol in South Africa. All of the previous systems are purpose-built and context-specific, so a new system is required for the South African setting. Previous prioritisation systems were assessed based on the attributes and methodology adopted. The attributes of previous systems were grouped into three sections, being (1) impact/importance of the target plant, (2) likelihood of achieving success, and (3) investment required. Nineteen attributes from previous systems are included in the new system, while nine were excluded due to a requirement for legislation and/or research, or because they conflicted with objectives of the new system in some way. Two methodological approaches were identified for how systems sourced information, either sourcing information through expert knowledge or the use of available literature and data. This information was then applied through either a quantitative or qualitative scoring method. A quantitative scoring method, with information sourced from available resources, was selected as the most appropriate methodology in the context of the new system for South Africa. This review streamlined the development and testing of the South African Biological Control Target Selection system.
Invasive alien plants (IAPs) are considered one of the greatest threats to biodiversity in South Africa and are often associated with negative socio-economic and human health consequences. Biocontrol ...is seen as an effective strategy for managing IAPs however it can realistically only be considered for a subset of such plants given the limited funding resources available. Some plants are also better targets for biocontrol than others. This paper develops a prioritisation system to create an objective, transparent and easily usable method in which to target IAPs plants that are most suited to biocontrol in South Africa. The Biological Control Target Selection (BCTS) system builds on twelve previously developed prioritisation systems. The system uses three sections encompassing thirteen attributes that are combined to present the highest predicative powers to rank potential target IAPs as biocontrol targets.
We contend that invasion ecology requires a universal, measurable trait of species and their interactions with resources that predicts key elements of invasibility and ecological impact; here, we ...advocate that functional responses can help achieve this across taxonomic and trophic groups, among habitats and contexts, and can hence help unify disparate research interests in invasion ecology.
Criticisms about the safety of biological control of alien plants has resulted in a risk-averse approach, where the risks posed by the agent are paramount and the risks posed by the alien plant are ...neglected. We argue that the risk associated with non-target damage from agents needs to be assessed relative to that of their target alien plants. A literature review of the non-target risks associated with biological control agents was undertaken in terms of the risk to native species from agents relative to the risk to native species from their alien plant targets. We then developed a framework that compares the consequence with the likelihood of non-target damage for both agents and their targets to provide an overall risk rating. Assessments of the risk of damage from both agents and their target alien plants will enable researchers, managers and policy makers to better assess the risks from biological control.
Riparian restoration is an important objective for landscape managers seeking to redress the widespread degradation of riparian areas and the ecosystem services they provide. This study investigated ...the long-term outcomes of ‘one-off’ restoration activities undertaken in the Upper Murrumbidgee Catchment, NSW, Australia. The objective of the restoration was to protect and enhance riparian vegetation and control erosion, and consequently reduce sediment and nutrient delivery into the Murrumbidgee River. To evaluate the outcomes 10 years after restoration, rapid riparian vegetation and geomorphological assessments were undertaken at 29 sites spanning the four different restoration methods used (at least five replicates per treatment), as well as at nine comparable untreated sites. We also trialed the use of aerial imagery to compare width of riparian canopy vegetation and projective foliage cover prior to restoration with that observed after 10 years. Aerial imagery demonstrated the width of riparian canopy vegetation and projective foliage cover increased in all restored sites, especially those with native plantings. The rapid assessment process indicated that 10 years after riparian restoration, the riparian vegetation was in a better condition at treated sites compared to untreated sites. Width of riparian canopy vegetation, native mid-storey cover, native canopy cover and seedling recruitment were significantly greater in treated sites compared to untreated sites. Geomorphological condition of treated sites was significantly better than untreated sites, demonstrating the importance of livestock exclusion to improve bank and channel condition. Our findings illustrate the value of ‘one-off’ restoration activities in achieving long-term benefits for riparian health. We have demonstrated that rapid assessments of the vegetation and geomorphological condition can be undertaken post-hoc to determine the long-term outcomes, especially when supported with analysis of historical aerial imagery.
Predicting the influence of climate change on the potential distribution of naturalised alien plant species is an important and challenging task. While prioritisation of management actions for alien ...plants under current climatic conditions has been widely adopted, very few systems explicitly incorporate the potential of future changes in climate conditions to influence the distribution of alien plant species. Here, we develop an Australia-wide screening tool to assess the potential of naturalised alien plants to establish and spread under both current and future climatic conditions. The screening tool developed uses five spatially explicit criteria to establish the likelihood of alien plant population establishment and expansion under baseline climate conditions and future climates for the decades 2035 and 2065. Alien plants are then given a threat rating according to current and future threat to enable natural resource managers to focus on those species that pose the largest potential threat now and in the future. To demonstrate the screening tool, we present results for a representative sample of approximately 10% (n = 292) of Australia's known, naturalised alien plant species. Overall, most alien plant species showed decreases in area of habitat suitability under future conditions compared to current conditions and therefore the threat rating of most alien plant species declined between current and future conditions. Use of the screening tool is intended to assist natural resource managers in assessing the threat of alien plant establishment and spread under current and future conditions and thus prioritise detailed weed risk assessments for those species that pose the greatest threat. The screening tool is associated with a searchable database for all 292 alien plant species across a range of spatial scales, available through an interactive web-based portal at http://weedfutures.net/.
•We develop a tool to assess threat of alien plants spreading under climate change.•The screening tool uses five spatially explicit criteria to establish a threat rating.•Most alien plant species modelled declined between current and future conditions.•Management can use the tool to prioritise high risk species for eradication.•Results can be queried through a web-based portal at http://weedfutures.net/.
There are many examples of cryptic species that have been identified through DNA‐barcoding or other genetic techniques. There are, however, very few confirmations of cryptic species being ...reproductively isolated. This study presents one of the few cases of cryptic species that has been confirmed to be reproductively isolated and therefore true species according to the biological species concept. The cryptic species are of special interest because they were discovered within biological control agent populations. Two geographically isolated populations of Eccritotarsus catarinensis (Carvalho) Hemiptera: Miridae, a biological control agent for the invasive aquatic macrophyte, water hyacinth, Eichhornia crassipes (Mart.) Solms Pontederiaceae, in South Africa, were sampled from the native range of the species in South America. Morphological characteristics indicated that both populations were the same species according to the current taxonomy, but subsequent DNA analysis and breeding experiments revealed that the two populations are reproductively isolated. Crossbreeding experiments resulted in very few hybrid offspring when individuals were forced to interbreed with individuals of the other population, and no hybrid offspring were recorded when a choice of mate from either population was offered. The data indicate that the two populations are cryptic species that are reproductively incompatible. Subtle but reliable diagnostic characteristics were then identified to distinguish between the two species which would have been considered intraspecific variation without the data from the genetics and interbreeding experiments. These findings suggest that all consignments of biological control agents from allopatric populations should be screened for cryptic species using genetic techniques and that the importation of multiple consignments of the same species for biological control should be conducted with caution.
A cryptic species of mirid bug was discovered using DNA‐Barding and confirmed as being reproductively isolated though interbreeding experiments. This is one of the first cryptic species to be confirmed as being reproductively isolated and therefore a true species according to the biological species concept. The cryptic species is of special interest because it is a biological control agent that is used for the control of an environmental weed.
AIM: Climate change and the ability of alien populations to realize different climatic niches compared to native populations pose challenges for pre‐empting invasion risk. These issues are not ...addressed in Weed Risk Assessments (WRAs), which have been developed to identify potentially invasive species and prevent their importation. Chrysanthemoides monilifera, native to Southern Africa, has two subspecies invasive in Australia, which has led to an importation ban on all six subspecies. We assess whether the two invasive subspecies occupy different realized climatic niches, compared with native populations, and the climatic suitability of Australia for all subspecies under current and future climate scenarios. LOCATION: Southern Africa and Australia METHODS: Realized climatic niches of native and alien populations of two invasive subspecies (Bitou Bush and Boneseed) were compared using niche identity tests. The distribution of climatically suitable habitat within Australia for all subspecies was modelled using MaxEnt, under current and future climate scenarios. For invasive subspecies, models were calibrated using (1) native or (2) alien range data. RESULTS: Realized climatic niches of native and alien populations are not identical, with some alien populations of Boneseed occupying climatic niches absent from Southern Africa. As such, MaxEnt models for Boneseed based on native range data failed to classify one‐third of Australian populations as inhabiting suitable climate. MAIN CONCLUSIONS: We validate the Australian decision to ban all subspecies by showing that climatically suitable habitat in Australia for non‐introduced subspecies exceeds that of introduced subspecies, under current and future climates. Niche shifts and climate change alter estimates of invasion risks, and this may reduce efficacy of current WRAs. We call for greater dialogue to identify and standardize a comprehensive system for incorporating these challenging issues into WRA systems to ensure that they remain effective in reducing the weed risk into the future.
Many members of the ETS-domain transcription factor family are important drivers of tumourigenesis. In this context, their activation by Ras-ERK pathway signaling is particularly relevant to the ...tumourigenic properties of many ETS-domain transcription factors. The PEA3 subfamily of ETS-domain transcription factors have been implicated in tumour metastasis in several different cancers.
Here, we have studied the expression of the PEA3 subfamily members PEA3/ETV4 and ER81/ETV1 in oesophageal adenocarcinomas and determined their role in oesophageal adenocarcinoma cell function. PEA3 plays an important role in controlling both the proliferation and invasive properties of OE33 oesophageal adenocarcinoma cells. A key target gene is MMP-1. The ERK MAP kinase pathway activates PEA3 subfamily members and also plays a role in these PEA3 controlled events, establishing the ERK-PEA3-MMP-1 axis as important in OE33 cells. PEA3 subfamily members are upregulated in human adenocarcinomas and expression correlates with MMP-1 expression and late stage metastatic disease. Enhanced ERK signaling is also more prevalent in late stage oesophageal adenocarcinomas.
This study shows that the ERK-PEA3-MMP-1 axis is upregulated in oesophageal adenocarcinoma cells and is a potentially important driver of the metastatic progression of oesophageal adenocarcinomas.
Many health and social needs can be assessed and met in community settings, where lower-cost, person-centered, preventative and proactive services predominate. This study reports on the development ...and implementation of a person-centered care model integrating dental, social, and health services for low-income older adults at a community dental clinic co-located within a senior wellness center.
A digital comprehensive geriatric assessment (CGA) and referral system linking medical, dental, and psychosocial needs by real-time CGA-derived metrics for 996 older adults (age ≥ 60) was implemented in 2016-2018 as part of a continuous quality improvement project. This study aims to describe: 1) the development and content of a new CGA; 2) CGA implementation, workflows, triage, referrals; 3) correlations between CGA domains, and adjusted regression models, assessing associations with self-reported recent hospitalizations, emergency department (ED) visits, and clinically-assessed dental urgency.
The multidisciplinary team from the senior wellness and dental centers planned and implemented a CGA that included standard medical history along with validated instruments for functional status, mental health and social determinants, and added oral health. Care navigators employed the CGA with 996 older adults, and made 1139 referrals (dental = 797, care coordination = 163, social work = 90, mental health = 32). CGA dimensions correlated between oral health, medical status, depressive symptoms, isolation, and reduced quality of life (QoL). Pain, medical symptoms, isolation and depressive symptoms were associated with poorer self-reported health, while general health was most strongly correlated with lower depressive symptoms, and higher functional status and QoL. Isolation was the strongest correlate of lower QoL. Adjusted odds ratios identified social and medical factors associated with recent hospitalization and ED visits. General and oral health were associated with dental urgency. Dental urgency was most strongly associated with general health (AOR = 1.78,95%CI 1.31, 2.43), dental symptoms (AOR = 2.39,95%CI 1.78, 3.20), dental pain (AOR = 2.06,95%CI 1.55-2.74), and difficulty chewing (AOR = 2.80, 95%CI 2.09-3.76). Dental symptoms were associated with recent ED visits (AOR = 1.61, 95%CI 1.12-2.30) or hospitalizations (AOR = 1.47, 95%CI 1.04-2.10).
Community-based inter-professional care is feasible with CGAs that include medical, dental, and social factors. A person-centered care model requires coordination supported by new workflows. Real-time metrics-based triage process provided efficient means for client review and a robust process to surface needs in complex cases.
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