Knowledge Gaps in Economic Costs of Invasive Alien Fish Worldwide

Invasive alien fishes have had pernicious ecological and economic impacts on both aquatic ecosystems and human societies. However, a comprehensive and collective assessment of their monetary costs is still lacking. In this study, we collected and reviewed reported data on the economic impacts of invasive alien fishes using InvaCost, the most comprehensive global database of invasion costs. We analysed how total (i.e. both observed and potential/predicted) and observed (i.e. empirically incurred only) costs of fish invasions are distributed geographically and temporally and assessed which socioeconomic sectors are most affected. Fish invasions have potentially caused the economic loss of at least US$37.08 billion (US2017 value) globally, from just 27 reported species. North America reported the highest costs (\u3e85$2.28 billion (6.1% of total costs), indicating that the costs of damage caused by invasive alien fishes are often extrapolated and/or difficult to quantify. Most of the observed costs were related to damage and resource losses (89%). Observed costs mainly affected public and social welfare (63%), with the remainder borne by fisheries, authorities and stakeholders through management actions, environmental, and mixed sectors. Total costs related to fish invasions have increased significantly over time, fro

The economic costs, management and regulation of biological invasions in the Nordic countries

A collective understanding of economic impacts and in particular of monetary costs of biological invasions is lacking for the Nordic region. This paper synthesizes findings from the literature on costs of invasions in the Nordic countries together with expert elicitation. The analysis of cost data has been made possible through the InvaCost database, a globally open repository of monetary costs that allows for the use of temporal, spatial, and taxonomic descriptors facilitating a better understanding of how costs are distributed. The total reported costs of invasive species across the Nordic countries were estimated at $8.35 billion (in 2017 US$ values) with damage costs significantly outweighing management costs. Norway incurred the highest costs ($3.23 billion), followed by Denmark ($2.20 billion), Sweden ($1.45 billion), Finland ($1.11 billion) and Iceland ($25.45 million). Costs from invasions in the Nordics appear to be largely underestimated. We conclude by highlighting such knowledge gaps, including gaps in policies and regulation stemming from expert judgment as well as avenues for an improved understanding of invasion costs and needs for future research.<br/

Accelerative and decelerative effects of hedonic valence and emotional arousal during visual scene processing

Perceptual processing of natural scene pictures is enhanced when the scene conveys emotional content. Such “motivated attention” to pleasant and unpleasant pictures has been shown to improve identification accuracy in non-speeded behavioural tasks. An open question is whether emotional content also modulates the speed of visual scene processing. In the present studies we show that unpleasant content reliably slowed two-choice categorization of pictures, irrespective of physical image properties, perceptual complexity, and categorization instructions. Conversely, pleasant content did not slow or even accelerated choice reactions, relative to neutral scenes. As indicated by lateralized readiness potentials, these effects occurred at cognitive processing rather than motor preparation/execution stages. Specifically, analysis of event-related potentials showed a prolongation of early scene discrimination for stimuli perceived as emotionally arousing, regardless of valence, and reflected in delayed peaks of the N1 component. In contrast, the timing of other processing steps, reflected in the P2 and late positive potential components and presumably related to post-discriminatory processes such as stimulus–response mapping, appeared to be determined by hedonic valence, with more pleasant scenes eliciting faster processing. Consistent with this model, varying arousal (low/high) within the emotional categories mediated the effects of valence on choice reaction speed. Functionally, arousal may prolong stimulus analysis in order to prevent erroneous and potentially harmful decisions. Pleasantness may act as a safety signal allowing rapid initiation of overt responses