scholarly journals Invasive species trait-based risk assessment for non-native freshwater fishes in a tropical city basin in Southeast Asia

PLoS ONE ◽  
2021 ◽  
Vol 16 (3) ◽  
pp. e0248480
Author(s):  
Joleen Chan ◽  
Yiwen Zeng ◽  
Darren C. J. Yeo

Biological invasions have created detrimental impacts in freshwater ecosystems. As non-native freshwater species include economically beneficial, but also harmful, species, trait-based risk assessments can be used to identify and prevent the import of potentially invasive species. Freshwater fishes are one of the most evaluated freshwater taxa to date. However, such assessments have mostly been done in sub-temperate to temperate regions, with a general lack of such research in the tropics. In view of this knowledge gap, this study aims to determine if a different set of traits are associated with successful establishment of non-native fishes within the tropics. In tropical Southeast Asia, Singapore represents a suitable model site to perform an invasive species trait-based risk assessment for the tropical region given its susceptibility to the introduction and establishment of non-native freshwater fishes and lack of stringent fish import regulation. A quantitative trait-based risk assessment was performed using random forest to determine the relative importance of species attributes associated with the successful establishment of introduced freshwater fishes in Singapore. Species having a match in climate, prior invasion success, lower absolute fecundity, higher trophic level, and involvement in the aquarium trade were found to have higher establishment likelihood (as opposed to native distributional range and maximum size being among the commonly identified predictors in subtropical/temperate trait-based risk assessments). To minimize invasive risk, incoming freshwater fishes could be screened in future for such traits, allowing lists of prohibited or regulated species to be updated. The findings could also potentially benefit the development of invasive species action plans and inform management decisions in the Southeast Asian region. Considering a geographical bias in terms of having relatively less documentation of biological invasions in the tropics, particularly Asia, this study highlights the need to perform more of such risk assessments in other parts of the tropics.

2018 ◽  
Vol 69 (7) ◽  
pp. 1159 ◽  
Author(s):  
P. Bayliss ◽  
C. M. Finlayson ◽  
J. Innes ◽  
A. Norman-López ◽  
R. Bartolo ◽  
...  

The internationally important river–floodplains of the Kakadu Region in northern Australia are at risk from invasive species and future sea-level rise–saltwater inundation (SLR–SWI), requiring assessments of multiple cumulative risks over different time frames. An integrated risk-assessment framework was developed to assess threats from feral animals and aquatic weeds at three SLR-scenario time frames (present-day, 2070 and 2100) to natural (magpie goose habitats), cultural (indigenous hunting–fishing sites) and economic (tourism revenue less invasive species control costs) values. Probability density functions (pdfs) were fitted to spatial data to characterise values and threats, and combined with Monte Carlo simulation and sensitivity analyses to account for uncertainties. All risks were integrated in a Bayesian belief network to undertake ‘what if’ management-scenario analyses, and incorporated known ecological interactions and uncertainties. Coastal landscapes and socio-ecological systems in the region will be very different by 2100 as a result of SLR; freshwater ecosystems will transform to marine-dominated ecosystems and cannot be managed back to analogue conditions. In this context, future invasive-species risks will decrease, reflecting substantial loss of freshwater habitats previously at risk and a reduction in the extent of invasive species, highlighting the importance of freshwater refugia for the survival of iconic species.


2016 ◽  
Vol 12 (4) ◽  
pp. 20151075 ◽  
Author(s):  
Stefano Fenoglio ◽  
Núria Bonada ◽  
Simone Guareschi ◽  
Manuel J. López-Rodríguez ◽  
Andrés Millán ◽  
...  

Biological invasions have increased significantly in response to global change and constitute one of the major causes of biodiversity loss. Insects make up a large fraction of invasive species, in general, and freshwaters are among the most invaded ecosystems on our planet. However, even though aquatic insects dominate most inland waters, have unparalleled taxonomic diversity and occupy nearly all trophic niches, there are almost no invasive insects in freshwaters. We present some hypotheses regarding why aquatic insects are not common among aquatic invasive organisms, suggesting that it may be the result of a suite of biological, ecological and anthropogenic factors. Such specific knowledge introduces a paradox in the current scientific discussion on invasive species; therefore, a more in-depth understanding could be an invaluable aid to disentangling how and why biological invasions occur.


2019 ◽  
Vol 76 (10) ◽  
pp. 1914-1921 ◽  
Author(s):  
Karl A. Lamothe ◽  
D. Andrew R. Drake

Freshwater ecosystems are among the most threatened environments on our planet. Disturbances across the terrestrial landscape accrue within freshwater ecosystems and, combined with global stressors such as climate change and invasive species, create a complex situation for recovering imperilled fishes. Given the drastic global decline of freshwater fishes, similarly extreme efforts are needed for their conservation and recovery — repatriation represents one such opportunity. Species repatriation describes the act of releasing a species in areas where extirpation has occurred. Paradoxically, a long history of fish introductions for recreational purposes exists, yet examples of repatriation for imperilled fishes are relatively rare compared with terrestrial species. Stemming from the restoration and species introduction literature, we identify five ecological themes to consider when evaluating repatriation potential of freshwater fishes and suggest that repatriation represents the “drastic” approach needed to achieve meaningful conservation milestones.


NeoBiota ◽  
2019 ◽  
Vol 48 ◽  
pp. 113-127 ◽  
Author(s):  
Jorge E. Ramírez-Albores ◽  
Ernesto I. Badano ◽  
Joel Flores ◽  
José Luis Flores-Flores ◽  
Laura Yáñez-Espinosa

Interest in invasive species has increased around the world over the last several decades. In Mexico, studies on invasive species date as early as 1939 and the number of publications has increased considerably in recent decades. However, to our knowledge, the analysis of information gaps and research priorities is lacking. Therefore, it is necessary to identify gaps in the knowledge of invasive species in order to define future research priorities and focus conservation efforts. We assessed the current state of knowledge of biological invasions in Mexico based on the existing literature. Our aim was to identify in which areas information is absent or insufficient and which areas should be prioritised. We identified a total of 869 references. The number of references increased over time and the topics were strongly biased towards two areas: 1) natural history and geographical distribution patterns and 2) effects on native biota and ecosystems. The remaining topics were only moderately or poorly studied. Most studies focused on vascular plants (n = 280) and fishes (n = 174). Notably, a large portion of the references (n = 215) focused on only eight invasive alien species, including their ecological and socioeconomic impacts. Only 95 references examined the effects of alien species on biodiversity; these studies were mainly carried out on islands (n = 41) or in terrestrial or freshwater ecosystems in protected natural areas (n = 165). The findings of the present review can guide future studies in filling in the existing research gaps on biological invasions. Additionally, future studies should aim to define national priorities of the impacts of biological invasions and to promote the prevention and control of alien species by considering the distinct vectors and pathways of introduction and movement.


2013 ◽  
Vol 154 (43) ◽  
pp. 1709-1712 ◽  
Author(s):  
Csaba Móczár

Introduction: Cardiovascular risk assessment may help in the identification of symptom-free subjects with high cardiovascular risk. Aim: The author studied the correlation between SCORE and Reynolds risk assessment systems based on data from the cardiovascular risk screening program carried out in subjects without cardiovascular disease. Method: Data obtained from 4462 subjects (1977 men and 2485 women; mean age, 47,4 years) were analysed. The comparison was based on risk categories of the SCORE system. Results: There was a strong correlation between the two scoring systems in the low risk population (under <2% SCORE risk the Spearman rho = 1, p < 0.001). A weak correlation was found in the medium risk group (between 3–4% the Spearman rho = 0.59–0.49, p < 0.001 and between 10–14% the Spearman rho = 0.42, ns.) and a stronger correlation in the high risk group (>15% the Spearmen rho = 0.8, p = 0.017). When correlations were analysed in gender and age categories, the weakest correlation was detected in medium risk women over 40 years of age. In cases when the differences between the two scoring systems were significant, the hsCRP levels were significantly higher (4.1 vs. 5.67 mg/L, p < 0.001). Conclusions: Introduction of hsCRP into cardiovascular risk assessments can refine the risk status of symptom-free subjects, especially among intermediate risk middle-age women (two-step risk assessment). Orv. Hetil., 154 (43), 1709–1712.


2005 ◽  
Vol 80 (3) ◽  
pp. 921-939 ◽  
Author(s):  
Ed O'Donnell ◽  
Joseph J. Schultz

Many auditors use an audit methodology that requires a strategic risk assessment of their client's business model as a first step for assessing audit risks. This study examines whether the holistic perspective that auditors acquire in making a strategic risk assessment influences the extent to which they adjust account-level risk assessments when they encounter changes in accounts that are inconsistent with information about client operations. Based on halo theory from the performance evaluation literature, we hypothesize that auditors who (1) perform (do not perform) strategic assessment, and (2) develop favorable (unfavorable) strategic risk assessments, are less (more) likely to adjust account-level risk assessments for inconsistent fluctuations. Data from two laboratory experiments using experienced auditors support both hypotheses. Findings suggest that the halo effect generated during strategic assessment influences judgment by altering auditor tolerance for inconsistent fluctuations.


Author(s):  
Grant Duwe

As the use of risk assessments for correctional populations has grown, so has concern that these instruments exacerbate existing racial and ethnic disparities. While much of the attention arising from this concern has focused on how algorithms are designed, relatively little consideration has been given to how risk assessments are used. To this end, the present study tests whether application of the risk principle would help preserve predictive accuracy while, at the same time, mitigate disparities. Using a sample of 9,529 inmates released from Minnesota prisons who had been assessed multiple times during their confinement on a fully-automated risk assessment, this study relies on both actual and simulated data to examine the impact of program assignment decisions on changes in risk level from intake to release. The findings showed that while the risk principle was used in practice to some extent, the simulated results showed that greater adherence to the risk principle would increase reductions in risk levels and minimize the disparities observed at intake. The simulated data further revealed the most favorable outcomes would be achieved by not only applying the risk principle, but also by expanding program capacity for the higher-risk inmates in order to adequately reduce their risk.


2021 ◽  
Vol 13 (2) ◽  
pp. 826
Author(s):  
Meiling Zhou ◽  
Xiuli Feng ◽  
Kaikai Liu ◽  
Chi Zhang ◽  
Lijian Xie ◽  
...  

Influenced by climate change, extreme weather events occur frequently, and bring huge impacts to urban areas, including urban waterlogging. Conducting risk assessments of urban waterlogging is a critical step to diagnose problems, improve infrastructure and achieve sustainable development facing extreme weathers. This study takes Ningbo, a typical coastal city in the Yangtze River Delta, as an example to conduct a risk assessment of urban waterlogging with high-resolution remote sensing images and high-precision digital elevation models to further analyze the spatial distribution characteristics of waterlogging risk. Results indicate that waterlogging risk in the city proper of Ningbo is mainly low risk, accounting for 36.9%. The higher-risk and medium-risk areas have the same proportions, accounting for 18.7%. They are followed by the lower-risk and high-risk areas, accounting for 15.5% and 9.6%, respectively. In terms of space, waterlogging risk in the city proper of Ningbo is high in the south and low in the north. The high-risk area is mainly located to the west of Jiangdong district and the middle of Haishu district. The low-risk area is mainly distributed in the north of Jiangbei district. These results are consistent with the historical situation of waterlogging in Ningbo, which prove the effectiveness of the risk assessment model and provide an important reference for the government to prevent and mitigate waterlogging. The optimized risk assessment model is also of importance for waterlogging risk assessments in coastal cities. Based on this model, the waterlogging risk of coastal cities can be quickly assessed, combining with local characteristics, which will help improve the city’s capability of responding to waterlogging disasters and reduce socio-economic loss.


2016 ◽  
Vol 27 (5) ◽  
pp. 474-490 ◽  
Author(s):  
Abderrahmane Bouda ◽  
Nour El Islam Bachari ◽  
Lylia Bahmed ◽  
Ryad Boubenia

Purpose – Ballast water of merchant ship is a source of introduction of invasive species around the globe. The purpose of this paper is to present a quantitative risk assessment applied to a model port, the Port of Arzew in Algeria, and based on an analysis of this port’s shipping traffic. Design/methodology/approach – The risk assessment for introduction of invasive species is interpreted in the form of a probabilistic process, with a combination of two probabilities. The first probability is related to the ability of a species to arrive to the destination (recipient port), depending on the quantity of water ballast discharged and the duration of voyage. The second one is based on the species ability to survive in their new environment, which depends on the environmental similarity between donor port and Arzew port. Findings – This assessment’s outcome consists on a classification of scenarios regarding their acceptability. Consequently, it helped to classify donor ports according to a risk scale, from low risk to high-risk donor ports. Research limitations/implications – The phenomenon of invasion of aquatic species is a complex process. Factors such as adaptation and tolerance of species, the attendance or absence of predators, were not taken into account in this study. Practical implications – This study could be used by the maritime administration as a decision-making tool regarding the issue of exemptions under the IMO International Convention on the Management of Ballast Water and Sediments 2004. Originality/value – This is one of the first known studies in Algeria and dealing with ballast water management. The results of this assessment provide useful information to policy makers, in order to develop a national strategy to reduce the impact of shipping pollution on the marine environment.


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