Taming the terminological tempest in invasion science

Standardised terminology in science is important for clarity of interpretation and communication. In invasion science – a dynamic and rapidly evolving discipline – the proliferation of technical terminology has lacked a standardised framework for its development. The result is a convoluted and inconsistent usage of terminology, with various discrepancies in descriptions of damage and interventions. A standardised framework is therefore needed for a clear, universally applicable, and consistent terminology to promote more effective communication across researchers, stakeholders, and policymakers. Inconsistencies in terminology stem from the exponential increase in scientific publications on the patterns and processes of biological invasions authored by experts from various disciplines and countries since the 1990s, as well as publications by legislators and policymakers focusing on practical applications, regulations, and management of resources. Aligning and standardising terminology across stakeholders remains a challenge in invasion science. Here, we review and evaluate the multiple terms used in invasion science (e.g. ‘non-native’, ‘alien’, ‘invasive’ or ‘invader’, ‘exotic’, ‘non-indigenous’, ‘naturalised’, ‘pest’) to propose a more simplified and standardised terminology. The streamlined framework we propose and translate into 28 other languages is based on the terms (i) ‘non-native’, denoting species transported beyond their natural biogeographic range, (ii) ‘established non-native’, i.e. those non-native species that have established self-sustaining populations in their new location(s) in the wild, and (iii) ‘invasive non-native’ – populations of established non-native species that have recently spread or are spreading rapidly in their invaded range actively or passively with or without human mediation. We also highlight the importance of conceptualising ‘spread’ for classifying invasiveness and ‘impact’ for management. Finally, we propose a protocol for classifying populations based on (i) dispersal mechanism, (ii) species origin, (iii) population status, and (iv) impact. Collectively and without introducing new terminology, the framework that we present aims to facilitate effective communication and collaboration in invasion science and management of non-native species

Evaluating the invasiveness of Acacia paradoxa in South Africa

We present the first detailed survey of a population of Acacia paradoxa DC. (syn. Acacia armata R.Br.), Kangaroo Thorn, in South Africa. The species is listed under the Conservation of Agricultural Resources Act as a category 1 invasive plant and, until 2008, was being managed as part of Working for Water's general alien clearing operations. Acacia paradoxa is currently restricted to a small population (~11,350 plants over ~295 ha) on the northern slopes of Devil's Peak, Table Mountain National Park in the Western Cape. Its distribution is highly clumped, and at a local scale it has formed thick stands of up to 20 plants m−2. Using a bioclimatic model we predict that it has a large potential distribution in South Africa, especially along the southern coast. We confirmed the categorisation of A. paradoxa as a potential landscape transformer that requires immediate control by conducting a formal risk assessment using the Australian Weed Risk Assessment system. However, the population appears to be spreading slowly, and, while there is a significant seed-bank in some places (~1000 seeds m−2), this is largely restricted to below the canopy of existing plants. Therefore, the population has not and likely will not rapidly spread in area, and so containment is feasible. Dedicated and thorough annual follow ups are required because plants can produce seeds when they are 1 year old and standard clearing operations have missed flowering plants.Working for Wate

Evaluating the invasiveness of Acacia paradoxa in South Africa

We present the first detailed survey of a population of Acacia paradoxa DC. (syn. Acacia armata R.Br.), Kangaroo Thorn, in South Africa. The species is listed under the Conservation of Agricultural Resources Act as a category 1 invasive plant and, until 2008, was being managed as part of Working for Water's general alien clearing operations. Acacia paradoxa is currently restricted to a small population (~ 11,350 plants over ~ 295 ha) on the northern slopes of Devil's Peak, Table Mountain National Park in the Western Cape. Its distribution is highly clumped, and at a local scale it has formed thick stands of up to 20 plants m- 2. Using a bioclimatic model we predict that it has a large potential distribution in South Africa, especially along the southern coast. We confirmed the categorisation of A. paradoxa as a potential landscape transformer that requires immediate control by conducting a formal risk assessment using the Australian Weed Risk Assessment system. However, the population appears to be spreading slowly, and, while there is a significant seed-bank in some places (~ 1000 seeds m- 2), this is largely restricted to below the canopy of existing plants. Therefore, the population has not and likely will not rapidly spread in area, and so containment is feasible. Dedicated and thorough annual follow ups are required because plants can produce seeds when they are 1 year old and standard clearing operations have missed flowering plants. © 2009 Elsevier B.V. All rights reserved.Articl

Multi-lingual literature searches are needed to unveil global knowledge

Scientific syntheses integrate and assess knowledge in a field of research by laying out the current state of knowledge and identifying gaps, thereby fostering research on new or overlooked questions (Pullin & Stewart, 2006; Wyborn et al., 2018). From an applied ecological perspective, scientific syntheses are important tools for comparing the effects of management actions across ecosystems. Through rigorous and comprehensive scientific syntheses, managers and researchers can learn what works best to increase the efficacy of solutions to ecological problems. Because of their integrative nature, scientific syntheses in Ecology often aim to be global in scope. However, standards for what characterizes a comprehensive research synthesis of global scope are variable and, currently, literature search efforts of published scientific syntheses rarely match their proposed scope. An important issue with global scientific syntheses is language as reviews and meta-analyses tend to limit the scope of their search to few or only one language

The importance of flower visitors not predicted by floral syndromes

Flower visitors that do not fit a perceived floral syndrome are often over-looked and deemed unimportant. In Tritoniopsis revoluta, an irid with a very long corolla tube conforming to the long proboscid fly pollination syndrome, we determine visitation rates of bees and long proboscid flies, as well as ascertain whether bees could be important pollen vectors in this system. We confirmed the presence of extremely long proboscid Prosoeca longipennis flies in one T. revoluta population, but found that fly visitation was absent in most populations. Instead, we found that in the absence of flies, nectar wells up the corolla tubes and becomes accessible to Amegilla bees, which were the most frequent visitors to T. revoluta at most sites and carried pollen, suggesting they could effect pollination. The highest bee visitation rates were in T. revoluta populations with unusually short tubed plants, where nectar was more accessible than in plants with long corolla tubes. Short tubed populations with more bee activity had higher average seed set than long tubed populations, suggesting that bees might contribute significantly to fitness in this apparently long-proboscid fly pollinated plant. Although these results do not support the use of syndromes for predicting all of a flower's important pollinators, they do support the idea that floral morphology will be shaped by the most effective pollinators at the time. © 2009 Elsevier B.V. All rights reserved.Articl

Corrigendum to "The importance of flower visitors not predicted by floral syndromes". [South African Journal of Botany. 2009, 75:660-667] (DOI:10.1016/j.sajb.2009.08.002)

[No abstract available]Erratu

The importance of flower visitors not predicted by floral syndromes

AbstractFlower visitors that do not fit a perceived floral syndrome are often over-looked and deemed unimportant. In Tritoniopsis revoluta, an irid with a very long corolla tube conforming to the long proboscid fly pollination syndrome, we determine visitation rates of bees and long proboscid flies, as well as ascertain whether bees could be important pollen vectors in this system. We confirmed the presence of extremely long proboscid Prosoeca longipennis flies in one T. revoluta population, but found that fly visitation was absent in most populations. Instead, we found that in the absence of flies, nectar wells up the corolla tubes and becomes accessible to Amegilla bees, which were the most frequent visitors to T. revoluta at most sites and carried pollen, suggesting they could effect pollination. The highest bee visitation rates were in T. revoluta populations with unusually short tubed plants, where nectar was more accessible than in plants with long corolla tubes. Short tubed populations with more bee activity had higher average seed set than long tubed populations, suggesting that bees might contribute significantly to fitness in this apparently long-proboscid fly pollinated plant. Although these results do not support the use of syndromes for predicting all of a flower's important pollinators, they do support the idea that floral morphology will be shaped by the most effective pollinators at the time