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Abstract
Background
Long-term biomonitoring of macroinvertebrates is a popular and valuable approach for assessing the status of freshwater ecosystems, identifying the impact of stressors, and evaluating ecosystem health. Although macroinvertebrate-based biomonitoring can be effective in detecting changes in distribution patterns and community trends over time, crayfish often remain undetected or unreported by biomonitoring efforts despite their importance in maintaining the functioning of aquatic ecosystems.

Results
By analyzing a comprehensive database of long-term macroinvertebrate time series, we found that most sampling methods and assessment schemes can detect both native and non-native crayfish in running waters if sites are continuously sampled. However, native crayfish were detected to a lesser extent and by fewer methods. Kick-net sampling and assessment techniques prevailed as the most efficient methods for capturing crayfish. However, the substantial number of time series lacking crayfish data calls into question whether these methods are sufficiently comprehensive to encapsulate crayfish populations accurately. The use of other targeted methods such as baited traps or hand catching may provide a more reliable estimate of their presence.

Conclusions
Given the detrimental impacts of non-native crayfish and the decline in native crayfish populations, we strongly recommend that stakeholders and managers incorporate a combination of these approaches into their monitoring efforts. The use of different taxonomic levels (family vs. genus vs. species level) in estimating biological indices and biomonitoring tools can cause delays in identifying new non-native specie's occurrences, hindering effective water quality assessment and ecosystem management by governments and stakeholders. Therefore, whenever possible, we call for standardized taxonomic levels for biomonitoring studies and management strategies to accurately address these issues and make recommendations going forward.

Part 4: Complex System Modelling and Simulation ; International audience ; The price of copper and its variations represent a very important financial issue for mining companies and for the Chilean government because of its impact on the national economy. The price of commodities such as copper is highly volatile, dynamic and troublous. Due to this, forecasting is very complex. Using publicly data from October 24th of 2013 to August 29th of 2014 a multivaried based model using meta-heuristic optimization techniques is proposed. In particular, we use Genetic Algorithms and Simulated Annealing in order to find the best fitting parameters to forecast the variation on the copper price. A non-parametric test proposed by Timmermann and Pesaran is used to demonstrate the forecasting capacity of the models. Our numerical results show that the Genetic Algorithmic approach has a better performance than Simulated Annealing, being more effective for long range forecasting.

AbstractIn today's ever-evolving scientific landscape, invasion science faces a plethora of challenges, such as terminological inconsistency and the rapidly growing literature corpus with few or incomplete syntheses of knowledge, which may be perceived as a stagnation in scientific progress. We explore the concept of 'competency', which is extensively debated across disciplines such as psychology, philosophy, and linguistics. Traditionally, it is associated with attributes that enable superior performance and continuous ingenuity. We propose that the concept of competency can be applied to invasion science as the ability to creatively and critically engage with global challenges. For example, competency may help develop innovative strategies for understanding and managing the multifaceted, unprecedented challenges posed by the spread and impacts of non-native species, as well as identifying novel avenues of inquiry for management. Despite notable advancements and the exponential increase in scholarly publications, invasion science still encounters obstacles such as insufficient interdisciplinary collaboration paralleled by a lack of groundbreaking or actionable scientific advancements. To enhance competency in invasion science, a paradigm shift is needed. This shift entails fostering interdisciplinary collaboration, nurturing creative and critical thinking, and establishing a stable and supportive environment for early career researchers, thereby promoting the emergence of competency and innovation. Embracing perspectives from practitioners and decision makers, alongside diverse disciplines beyond traditional ecological frameworks, can further add novel insights and innovative methodologies into invasion science. Invasion science must also address the ethical implications of its practices and engage the public in awareness and education programs. Such initiatives can encourage a more holistic understanding of invasions, attracting and cultivating competent minds capable of thinking beyond conventional paradigms and contributing to the advancement of the field in a rapidly changing world.

Abstract
Background
Biological invasions threaten the functioning of ecosystems, biodiversity, and human well-being by degrading ecosystem services and eliciting massive economic costs. The European Union has historically been a hub for cultural development and global trade, and thus, has extensive opportunities for the introduction and spread of alien species. While reported costs of biological invasions to some member states have been recently assessed, ongoing knowledge gaps in taxonomic and spatio-temporal data suggest that these costs were considerably underestimated.

Results
We used the latest available cost data in InvaCost (v4.1)—the most comprehensive database on the costs of biological invasions—to assess the magnitude of this underestimation within the European Union via projections of current and future invasion costs. We used macroeconomic scaling and temporal modelling approaches to project available cost information over gaps in taxa, space, and time, thereby producing a more complete estimate for the European Union economy. We identified that only 259 out of 13,331 (~ 1%) known invasive alien species have reported costs in the European Union. Using a conservative subset of highly reliable, observed, country-level cost entries from 49 species (totalling US$4.7 billion; 2017 value), combined with the establishment data of alien species within European Union member states, we projected unreported cost data for all member states.

Conclusions
Our corrected estimate of observed costs was potentially 501% higher (US$28.0 billion) than currently recorded. Using future projections of current estimates, we also identified a substantial increase in costs and costly species (US$148.2 billion) by 2040. We urge that cost reporting be improved to clarify the economic impacts of greatest concern, concomitant with coordinated international action to prevent and mitigate the impacts of invasive alien species in the European Union and globally.