Western flower thrips,
, first arose as an important invasive pest of many crops during the 1970s-1980s. The tremendous growth in international agricultural trade that developed then fostered the ...invasiveness of western flower thrips. We examine current knowledge regarding the biology of western flower thrips, with an emphasis on characteristics that contribute to its invasiveness and pest status. Efforts to control this pest and the tospoviruses that it vectors with intensive insecticide applications have been unsuccessful and have created significant problems because of the development of resistance to numerous insecticides and associated outbreaks of secondary pests. We synthesize information on effective integrated management approaches for western flower thrips that have developed through research on its biology, behavior, and ecology. We further highlight emerging topics regarding the species status of western flower thrips, as well as its genetics, biology, and ecology that facilitate its use as a model study organism and will guide development of appropriate management practices.
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•The accuracy of species distribution models is influenced by physiological tolerance data.•The red-eared slider, as a typical invasive alien species, is widespread in China.•The ...embryo temperature tolerance range of the red-eared slider was between 21.8 °C and 33.1 °C.•Red-eared slider’s high suitability areas mainly in south and central. The suitability areas predicted by the SDMs reduced 20% when considering embryo temperature tolerance data of red-eared slider.•The high suitability areas for red-eared sliders are mainly concentrated in South China, Central China, and East China.
Species distribution models (SDMs) have been widely used to predict potentially suitable habitats for invasive alien species (IAS) and evaluate invasion risk. However, SDMs have been discredited because they ignore the physiological processes by which species respond to their environment. Integrating physiological tolerance into the model is essential to improve the prediction accuracy of SDMs. Currently, this approach has not been applied in the study of the worldwide invasive species, the red-eared slider (Trachemys scripta elegans), which is one of the world’s 100 worst invasive species and is widespread in China. In this study, based on hatching experiments, we found that the embryo temperature tolerance range of the red-eared slider was between 21.8 °C and 33.1 °C. Further, we studied the effect of embryo temperature tolerance on the prediction of potential invasion areas for this alien reptile species. The high suitability area (530,214.71 km2) predicted by the SDM incorporating embryo temperature tolerance data were 20.9% smaller than that (641,107.60 km2) predicted by the SDM without considering embryo temperature tolerance. The difference between the two SDMs is primarily concentrated at the edges of the high suitability areas. The incorporation of embryo temperature tolerance data influenced the model's predictions by effectively reducing the extent of edges of the high suitability areas. High suitability areas for red-eared sliders are mainly concentrated in South China, Central China, and East China, with a few in North and Southwest China. There is almost no invasion risk in most of the northeast and northwest provinces of China. This study not only has theoretical significance for optimizing model predictions, but also provides an important scientific basis for prevention and risk assessment of invasion by red-eared sliders in China.
The United States has thousands of invasive species, representing a sizable, but unknown burden to the national economy. Given the potential economic repercussions of invasive species, quantifying ...these costs is of paramount importance both for national economies and invasion management. Here, we used a novel global database of invasion costs (InvaCost) to quantify the overall costs of invasive species in the United States across spatiotemporal, taxonomic, and socioeconomic scales. From 1960 to 2020, reported invasion costs totaled $4.52 trillion (USD 2017). Considering only observed, highly reliable costs, this total cost reached $1.22 trillion with an average annual cost of $19.94 billion/year. These costs increased from $2.00 billion annually between 1960 and 1969 to $21.08 billion annually between 2010 and 2020. Most costs (73%) were related to resource damages and losses ($896.22 billion), as opposed to management expenditures ($46.54 billion). Moreover, the majority of costs were reported from invaders from terrestrial habitats ($643.51 billion, 53%) and agriculture was the most impacted sector ($509.55 billion). From a taxonomic perspective, mammals ($234.71 billion) and insects ($126.42 billion) were the taxonomic groups responsible for the greatest costs. Considering the apparent rising costs of invasions, coupled with increasing numbers of invasive species and the current lack of cost information for most known invaders, our findings provide critical information for policymakers and managers.
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•From 1960 to 2020 reported costs of US biological invasions were at least $1.22 tril.•Annual invasion costs increased from $2 bil in 1960–69 to $21 bil in 2010–20.•Most costs were damages ($896 bil), with lower management investments ($47 bil).•Agriculture sector ($510 bil) and terrestrial habitat ($644 bil) were impacted most.•Knowledge gaps in reporting make these monetary costs severely underestimated.
Aim: To use global databases to (1) provide a visualization of global geographical patterns of species invasions, origins and pathways and (2) depict the international uptake of legislative and ...policy responses to invasive alien species (IAS). Location: Global. Methods: Patterns of recorded species invasions and pathways of introduction were mapped and visualized using data from the Global Invasive Species Database (GISD) and the CABI Invasive Species Compendium (CABI ISC), along with associated legal instruments relevant to IAS compiled from the ECOLEX database. A novel indicator of the asymmetry between each country's 'ingress/egress' of IAS (kappa, K), was developed to further explore spatial patterns. Results: Substantial variation in the spatial patterns of invasion was determined, with the Global North, some newly industrialized countries and small tropical islands being the main recipients of IAS and asymmetry (K) being highest in New World countries and small islands. Of the 1517 recorded IAS, 39% were introduced only intentionally and 26% only unintentionally, 22% both intentionally and unintentionally, while 13% had no information available. The dominant pathway for species invasions was horticulture and the nursery trade, with 31% of the species introduced outside of their natural geographical range. Large increases in legislation on IAS have occurred since the 1990s, particularly for those countries that have high numbers of species invasions. Main conclusions: Clear global patterns in the distributions of IAS are determined, supporting arguments emphasizing the role of colonial history, economic development and trade in driving the human-mediated movement of species. Dominant pathways for species invasions are similar across different regions. Policy responses towards IAS show an increasing desire from the international community to act on species invasions. Current patterns suggest that Africa and Central Asia are priority areas for future IAS research and control.
Biological invasions are a global threat to biodiversity. Since the spread of invasive alien plants may have many impacts, an integrated approach, assessing effects across various ecosystem ...components, is needed for a correct understanding of the invasion process and its consequences. The nitrogen-fixing tree Robinia pseudoacacia (black locust) is a major invasive species worldwide and is used in forestry production. While its effects on plant communities and soils are well known, there have been few studies on soil fauna and microbes.
We investigated the impacts of the tree on several ecosystem components, using a multi-trophic approach to combine evidence of soil chemical properties and soil microbial, nematode, microarthropod and plant communities. We sampled soil and vegetation in managed forests, comparing those dominated by black locust with native deciduous oak stands.
We found qualitative and quantitative changes in all components analysed, such as the well-known soil nitrification and acidification in stands invaded by black locust. Bacterial richness was the only component favoured by the invasion. On the contrary, abundance and richness of microarthropods, richness of nematodes, and richness and diversity of plant communities decreased significantly in invaded stands. The invasion process caused a compositional shift in all studied biotic communities and in relationships between the different ecosystem components.
We obtained clear insights into the effects of invasion of managed native forests by black locust. Our data confirms that the alien species transforms several ecosystem components, modifying the plant-soil community and affecting biodiversity at different levels. Correct management of this aggressive invader in temperate forests is urgently required.
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•We analysed the impacts of Robinia pseudoacacia invasion.•We analysed impacts on soil chemical properties, plant and soil biotic communities.•We found qualitative and quantitative changes in all components analysed.•We detected soil nitrification and acidification in stands invaded by black locust.•Changes (mostly biodiversity reduction) were observed in biotic communities.
Addressing context dependence in ecology Catford, Jane A.; Wilson, John R.U.; Pyšek, Petr ...
Trends in ecology & evolution (Amsterdam),
February 2022, 2022-02-00, 20220201, Letnik:
37, Številka:
2
Journal Article
Recenzirano
Odprti dostop
Context dependence is widely invoked to explain disparate results in ecology. It arises when the magnitude or sign of a relationship varies due to the conditions under which it is observed. Such ...variation, especially when unexplained, can lead to spurious or seemingly contradictory conclusions, which can limit understanding and our ability to transfer findings across studies, space, and time. Using examples from biological invasions, we identify two types of context dependence resulting from four sources: mechanistic context dependence arises from interaction effects; and apparent context dependence can arise from the presence of confounding factors, problems of statistical inference, and methodological differences among studies. Addressing context dependence is a critical challenge in ecology, essential for increased understanding and prediction.
‘Context dependence’ is widely used to describe disparate results in ecology, but the term is poorly defined and inconsistently used.Context dependence arises when ecological relationships vary in magnitude or sign, depending on the conditions under which they are observed.Context dependence can result from multiple factors and processes, so, unless the underlying causes are identified, concluding that relationships are context dependent provides limited understanding.We distinguish between apparent and mechanistic context dependence, with the former an artefact of study design and approach and the latter reflecting ecological interaction effects.Recognising and addressing the different sources of context dependence should facilitate increased understanding, prediction, and generalisation in ecology.
The global increase in biological invasions is placing growing pressure on the management of ecological and economic systems. However, the effectiveness of current management expenditure is difficult ...to assess due to a lack of standardised measurement across spatial, taxonomic and temporal scales. Furthermore, there is no quantification of the spending difference between pre-invasion (e.g. prevention) and post-invasion (e.g. control) stages, although preventative measures are considered to be the most cost-effective. Here, we use a comprehensive database of invasive alien species economic costs (InvaCost) to synthesise and model the global management costs of biological invasions, in order to provide a better understanding of the stage at which these expenditures occur. Since 1960, reported management expenditures have totalled at least US$95.3 billion (in 2017 values), considering only highly reliable and actually observed costs — 12-times less than damage costs from invasions ($1130.6 billion). Pre-invasion management spending ($2.8 billion) was over 25-times lower than post-invasion expenditure ($72.7 billion). Management costs were heavily geographically skewed towards North America (54%) and Oceania (30%). The largest shares of expenditures were directed towards invasive alien invertebrates in terrestrial environments. Spending on invasive alien species management has grown by two orders of magnitude since 1960, reaching an estimated $4.2 billion per year globally (in 2017 values) in the 2010s, but remains 1–2 orders of magnitude lower than damages. National management spending increased with incurred damage costs, with management actions delayed on average by 11 years globally following damage reporting. These management delays on the global level have caused an additional invasion cost of approximately $1.2 trillion, compared to scenarios with immediate management. Our results indicate insufficient management — particularly pre-invasion — and urge better investment to prevent future invasions and to control established alien species. Recommendations to improve reported management cost comprehensiveness, resolution and terminology are also made.
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•Since 1960, management for biological invasions totalled at least $95.3 billion.•Damage costs from invasions were substantially higher ($1130.6 billion).•Pre-invasion management spending is 25-times lower than post-invasion.•Management and damage costs are increasing rapidly over time.•Proactive management substantially reduces future costs at the trillion-$ scale.
Crypticity in Biological Invasions Jarić, Ivan; Heger, Tina; Castro Monzon, Federico ...
Trends in ecology & evolution (Amsterdam),
April 2019, 2019-Apr, 2019-04-00, 20190401, Letnik:
34, Številka:
4
Journal Article
Recenzirano
Ecological effects of alien species can be dramatic, but management and prevention of negative impacts are often hindered by crypticity of the species or their ecological functions. Ecological ...functions can change dramatically over time, or manifest after long periods of an innocuous presence. Such cryptic processes may lead to an underestimation of long-term impacts and constrain management effectiveness. Here, we present a conceptual framework of crypticity in biological invasions. We identify the underlying mechanisms, provide evidence of their importance, and illustrate this phenomenon with case studies. This framework has potential to improve the recognition of the full risks and impacts of invasive species.
Crypticity of biological invasions may blur invasion impacts and reduce their predictability.
The impacts are often only detected in retrospect, and understood with delay, long after control measures would have been effective.
Crypticity of biological invasions can be driven by inherent crypticity of alien species and their ecological functions and by time lags, spatio-temporal variability, and anthropogenic impacts.
Considering crypticity in biological invasions would strongly enhance efficiency of monitoring and management planning.
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