Citizen science provides added value in the monitoring for coastal non-indigenous species

Continuous and comprehensive monitoring is one of the most important practices to trace changes in the state of the environment and target management efforts. Yet, governmental resources are often insufficient for monitoring all required environmental parameters, and therefore authorities have started to utilize citizen observations to supplement and increase the scale of monitoring. The aims of the present study were to show the potential of citizen science in environmental monitoring by utilising citizen observations of the non-indigenous Harris mud crab Rhithropanopeus harrisii in Finnish waters, where coastal monitoring is insufficient to estimate the distribution and spread of non-indigenous species. Harris mud crab has shown measurable impact locally and is considered invasive. For reporting the status of invasions to national and European authorities and planning for potential eradication efforts, up to date knowledge on NIS ranges are needed. Citizen observations on the species were collected from the first observation onwards between 2009 and 2018, at first via email and later through an active citizen observation web portal (Invasive Alien Species Portal). The outcomes of the study indicate that species-specific citizen observations can be a beneficial addition to supplement national monitoring programs to fulfil legislative reporting requirements and to target potential management. Recognizable species and geographical areas with low biodiversity provide a good opportunity to utilize citizen observations. Moreover, citizen observations may enable distribution assessments for certain species that would otherwise require excessive resources and sampling efforts. Highlights • Citizen observations are cost-efficient addition to routine monitoring. • Citizen science can provide presence data on dist inctly recognizable species. • Citizen science provides important information to target management actions. • Citizen science enables estimates for species distribution

Monitoring of sessile and mobile epifauna – Considerations for non-indigenous species

The present study aimed to develop monitoring methods for shallow water sessile and mobile epifauna with the main focus on enhancing the chance of early detection for new non-indigenous species (NIS) invasions. The field sampling was conducted between June and September in 2012, in the Archipelago Sea (Finland). The tested monitoring methods included baited traps that capture organisms and habitat collectors that provide habitat and refuges for organisms, as well as fouling plates. Catch efficiency of a trap/collector was defined as the number of NIS and all species caught, including their abundances. The American collector with oyster shells (habitat collector) caught the highest number of NIS, and their use is recommended in all places, where oyster shells are easily accessible. Sampling of all habitats of interest between 1 and 2 m depth is recommended with at least three habitat collectors per site. Highlights • Sampling of mobile and sessile epifauna with habitat collectors is recommended. • Habitat traps should provide attachment surfaces, habitats and refuges to organisms. • Sampling of all habitats present between 1 and 2 m depth is recommended. • Deployment of 3 collectors per site is suggested for routine coastal monitoring. • Timing and duration of sampling may differ significantly between geographical areas

Counting stars: contribution of early career scientists to marine and fisheries sciences

Scientific careers and publishing have radically changed in recent decades creating an increasingly competitive environment for early career scientists (ECS). The lack of quantitative data available on ECS in marine and fisheries sciences prevents direct assessment of the consequences of increased competitiveness. We assessed the contributions of ECS (up to 6 years post first publication) to the field using an indirect approach by investigating the authorships of peer-reviewed articles. We analysed 118461 papers published by 184561 authors in the top 20 marine and fisheries sciences journals over the years 1991–2020. We identified a positive long-term trend in the proportion of scientific articles (co-)authored by ECS. This suggests a growing contribution by ECS to publications in the field. However, the mean proportion of ECS (co-)authors within one publication declined significantly over the study period. Subsequent tests demonstrated that articles with ECS (co-)authors receive fewer citations and that the proportion of ECS (co-)authors on an article has a significant negative effect on the number of citations. We discuss the potential causes of these inequalities and urge systematic support to ECS to achieve more balanced opportunities for funding and publishing between ECS and senior scientists

Exceptions and exemptions under the ballast water management convention – Sustainable alternatives for ballast water management?

Highlights • Data quality is very important for conducting a reliable risk assessment. • Same locations should be confined to smallest practicable areas within a port. • Nearly all shipping routes with adequate data resulted in high-risk outcomes. • Pelagic larval traits are key factors in natural dispersal modelling assessments.The International Convention for the Control and Management of Ships' Ballast Water and Sediments (BWM Convention) aims to mitigate the introduction risk of harmful aquatic organisms and pathogens (HAOP) via ships’ ballast water and sediments. The BWM Convention has set regulations for ships to utilise exceptions and exemptions from ballast water management under specific circumstances. This study evaluated local and regional case studies to provide clarity for situations, where ships could be excepted or exempted from ballast water management without risking recipient locations to new introductions of HAOP. Ships may be excepted from ballast water management if all ballasting operations are conducted in the same location (Regulation A-3.5 of the BWM Convention). The same location case study determined whether the entire Vuosaari harbour (Helsinki, Finland) should be considered as the same location based on salinity and composition of HAOP between the two harbour terminals. The Vuosaari harbour case study revealed mismatching occurrences of HAOP between the harbour terminals, supporting the recommendation that exceptions based on the same location concept should be limited to the smallest feasible areas within a harbour. The other case studies evaluated whether ballast water exemptions could be granted for ships using two existing risk assessment (RA) methods (Joint Harmonised Procedure [JHP] and Same Risk Area [SRA]), consistent with Regulation A-4 of the BWM Convention. The JHP method compares salinity and presence of target species (TS) between donor and recipient ports to indicate the introduction risk (high or low) attributed to transferring unmanaged ballast water. The SRA method uses a biophysical model to determine whether HAOP could naturally disperse between ports, regardless of their transportation in ballast water. The results of the JHP case study for the Baltic Sea and North-East Atlantic Ocean determined that over 97% of shipping routes within these regions resulted in a high-risk indication. The one route assessed in the Gulf of Maine, North America also resulted in a high-risk outcome. The SRA assessment resulted in an overall weak connectivity between all ports assessed within the Gulf of the St. Lawrence, indicating that a SRA-based exemption would not be appropriate for the entire study area. In summary, exceptions and exemptions should not be considered as common alternatives for ballast water management. The availability of recent and detailed species occurrence data was considered the most important factor to conduct a successful and reliable RA. SRA models should include biological factors that influence larval dispersal and recruitment potential (e.g., pelagic larval duration, settlement period) to provide a more realistic estimation of natural dispersal

National marine NIS assessment - Raw_data_REVISED

The raw data tables include all species records and abundances collected from Finnish open database for assessing the abundance and distribution of already established NIS, as well as NIS proportions in all samples and the calculations needed to assess community biodiversity index for all sub-basins and assessment periods.</p

Meta-analysis on the ecological impacts of widely spread non-indigenous species in the Baltic Sea

Highlights: • Effects of widespread NIS on ecosystem features and properties were quantified. • Most impactful NIS, processes underlying the changes and sources of uncertainty were identified. • Among communities, fish have been impacted the most while the pelagic realm is more affected than the benthic. • Significant effects were evident on the entire food web. • The effect size method offers a robust approach for general applications on quantification of the effects of NIS. Abstract: The introduction of non-indigenous species (NIS) is a major driver for global change in species biogeography, often associated with significant consequences for recipient ecosystems and services they provide for humans. Despite mandated by several high-level international legislative instruments, comprehensive quantitative evaluation on ecosystem impacts of marine NIS is scarce and lack a robust and data-driven assessment framework. The current study is aiming at fulfilling this gap, through quantitative assessment on the effects of the widespread NIS of the Baltic Sea on multiple ecosystem features and components including direct food-web effects. The outcomes of this study allowed identifying the most impacting widespread NIS, together with defining the processes underlying the most significant changes and outlined major sources of uncertainty. Lack and/or bias in the availability of evidence of impacts was recorded for several (both recent and early) introductions. Realizing a sophisticated, data and information-hungry framework for the evaluation of ecosystem impacts of NIS is not pragmatic for management purposes in the foreseeable future. Instead, simple approaches, such as application of common statistical parameters like absolute effect size, are more likely to result in tangible outcomes. As bearing no unit, effect sizes can be later easily aggregated across taxa, affected ecosystem features or spatial scales. The proposed approach enables performing systematic comparisons on the severity of impacts of different NIS along different study disciplines and ecosystems

Quantifying impacts of human pressures on ecosystem services : Effects of widespread non-indigenous species in the Baltic Sea

Highlights •This paper presents a framework to evaluate the effects of non-indigenous species (NIS) on ecosystem services (ES). •All studied NIS pose large and significant effects on ES. •Applicability of the framework extends to all realms. •Implementation of the framework will assist in moving to evidence-based assessments of NIS impacts. Abstract Ecosystem services (ES) are the benefits natural ecosystems provide to society, such as food provisioning, water supply, climate regulation and recreational benefits. Biological invasions are a major driver of global change, and several non-indigenous species (NIS) may alter key ecological feedbacks with ultimate consequences to ES, livelihoods and human wellbeing. Nonetheless, the effects of NIS on ES supply remain largely unquantified. Here we present the first quantitative case study assessing the impacts of widespread NIS on ES in the Baltic Sea, by developing and employing a robust and repeatable data-driven approach. All NIS with a sufficient knowledge base pose large and highly significant effects on ES, resulting on average 55 % change in the intensity of ES. Most impacts affected regulation services, concerning both abiotic and biotic realms, with little evidence on cultural and provisioning services. The methodology can be easily employed beyond the current study realm e.g. to better understand the roles of human pressures on ES in any ecosystem. Importantly, the study also identified major biases not only in the availability of taxonomic and sub-regional evidence, but also in the different study types employed to create the evidence base

Biological testing of ships’ ballast water indicates challenges for the implementation of the Ballast Water Management Convention

Ships’ ballast water and sediments are vectors that contribute to the unintentional spread of aquatic non-native species globally. Ballast water management, as well as commissioning testing of ballast water management systems and compliance monitoring under the regulations of the International Maritime Organization (IMO) aim at minimizing the unwanted spread of organisms. This study compiles data for treated ballast water samples collected and analyzed from 228 ships during 2017–2023. The samples were collected from the ballast discharge line or directly from the ballast tank for enumeration of living organism concentrations in the categories of ≥50µm and &lt;50 to ≥10µm -sized organisms, as well as indicator microbes in comparison to the ballast water performance standard of the IMO (Regulation D-2). In addition, several ship-specific factors were examined to infer potential factors affecting compliance rates. Nearly all ships were compliant with the ballast water performance standard for indicator microbes and &lt;50 to ≥10µm -sized organisms, whereas almost half of all samples exceeded the limit of ten viable organisms m-3 for the ≥50µm -sized organisms. Compliance testing results did not differ significantly between sampling years, indicating that compliance rate did not change through time. The rate of compliance was higher for commissioning testing than compliance testing. Clear ship- or system-specific factors that lead to compliance or non-compliance were not detected, even though type of ballast water management system, filter mesh size associated with the system and source of ballast water affected compliance significantly either for the samples taken from the discharge line, or ballast tank. As compliance did not improve significantly over time, compliance testing of ships’ ballast water should be undertaken to ensure that the systems remain operational after commissioning and ships meet requirements of the D-2 standard. Furthermore, the study outcomes promote further research on the efficiency of filter mesh sizes and different filtration units associated with ballast water management systems, to improve mechanical removal of larger organisms. Finally, as several ships exceeded the compliance limit by hundreds or thousands of living organisms, technological advancements and operational measures may be needed to improve the overall reliability of ballast water management