Miqueleiz-Legaz, I. (Imanol)

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    Effective reassessments of freshwater fish species: a case study in a Mediterranean peninsula
    (2022) Miqueleiz-Legaz, I. (Imanol); Miranda-Ferreiro, R. (Rafael); Cancellario, T. (Tommaso); Ariño-Plana, A.H. (Arturo Hugo)
    IUCN Red List assessments for fish species can quickly become out of date. In recent years molecular techniques have added new ways of obtaining information about species distribution or populations. In this work, we propose the Iberian Peninsula as an example of reassessment needs in its endangered freshwater fish fauna. We compiled the list of freshwater fish species occurring in continental Spain and Portugal and examined their conservation status in global and national Red Lists. We retrieved records for these species in the Iberian Peninsula and calculated several biological indexes (richness and vulnerability indexes). Our results showed a patchy data coverage of fish records in the Iberian Peninsula. Threat levels reported within national Red Lists are higher than their global counterparts, reinforcing the necessity of improving and maintaining up to date national Red Lists. Iberian watersheds have moderate levels of threat and high levels of out of date assessments. The nearly fully completed genetic databases for Iberian fish species, along with the limited distribution of many endangered species and the necessity of update their assessments constitute an excellent opportunity to use data obtained from eDNA to improve species monitoring practices and their conservation status.
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    Conservation-status gaps for marine top-fished commercial species
    (2022) Miqueleiz-Legaz, I. (Imanol); Miranda-Ferreiro, R. (Rafael); Ojea, E. (Elena); Ariño-Plana, A.H. (Arturo Hugo)
    Biodiversity loss is a global problem, accelerated by human-induced pressures. In the marine realm, one of the major threats to species conservation, together with climate change, is overfishing. In this context, having information on the conservation status of target commercial marine fish species becomes crucial for assuring safe standards. We put together fisheries statistics from the FAO, the IUCN Red List, FishBase, and RAM Legacy databases to understand to what extent top commercial species¿ conservation status has been assessed. Levels of assessment for top-fished species were higher than those for general commercial or highly commercial species, but almost half of the species have outdated assessments. We found no relation between IUCN Red List traits and FishBase Vulnerability Index, depreciating the latter value as a guidance for extinction threat. The RAM database suggests good management of more-threatened species in recent decades, but more data are required to assess whether the trend has reverted in recent years. Outdated IUCN Red List assessments can benefit from reputed stock assessments for new reassessments. The future of IUCN Red List evaluations for commercial fish species relies on integrating new parameters from fisheries sources and improved collaboration with fisheries stakeholders and managers.
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    Assessment gaps and biases in knowledge of conservation status of fishes
    (2020) Miranda, R. (Rafael); Miqueleiz-Legaz, I. (Imanol); Bohm, M. (Monika); Ariño-Plana, A.H. (Arturo Hugo)
    More than 33,500 fish species inhabit freshwater and marine environments, according to FishBase database records. The International Union for the Conservation of Nature (IUCN) has assessed the conservation status of approximately half of them, the lowest percentage in any vertebrate group. In order to identify what factors may underlie this assessment gap, several traits were examined related to distribution, life-history, taxonomy, conservation, and the economic relevance of species according to their assessment status. IUCN assessment patterns were explored and separate analyses were included for freshwater and marine species. The results showed that IUCN assessments were biased towards economically developed regions, species with early description dates and species covered by current IUCN specialist groups. Species living in remote areas or habitats were more likely to be unassessed. In particular, South America had low assessment levels. Other traits such as commercial importance did not influence the assessment status of fish species. We therefore encourage assessment in poorly assessed areas and taxonomic subgroups to prompt timely conservation action to prevent species extinctions.
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    Fish conservation in the 21st century: Lessons learned and perspectives for a sustainable future
    (2021-06-24) Miqueleiz-Legaz, I. (Imanol); Miranda-Ferreiro, R. (Rafael); Ariño-Plana, A.H. (Arturo Hugo)
    Las acciones humanas amenazan gravemente la biodiversidad acuática. De entre todos los vertebrados que viven en los ambientes acuáticos, los peces son los más diversos y esenciales por el papel que juegan en los ecosistemas acuáticos. Anteriormente, el estado de conservación de los peces ha sido evaluado gradualmente por la Lista Roja de la IUCN, pero aún están peor evaluados que otros vertebrados. Por ello, se necesitan más estudios para entender la conservación de los peces y proponer nuevas soluciones que mejoren sus evaluaciones y su estado de conservación y viabilidad. En este trabajo, comenzamos por evaluar la completitud de las evaluaciones de los peces en la Lista Roja de la IUCN. Al encontrar un 50% de especies sin evaluar, analizamos los rasgos de las especies de peces para explicar cuáles están influyendo en su evaluación, distinguiendo entre especies dulceacuícolas y marinas e identificando varias razones biogeográficas, biológicas y sociales. También analizamos el sesgo de evaluación en los peces de mayor importancia comercial, que resaltaron en el primer análisis. Evaluamos su estado de conservación con relación a los datos disponibles sobre capturas declaradas y reconstruidas, y sus implicaciones en la sostenibilidad de las pesquerías. Expandimos el estudio de las evaluaciones de la Lista Roja de la IUCN para incluir las tendencias de evaluación de peces en las últimas décadas. Analizamos las evaluaciones y evaluamos el papel de cada país en la conservación de los peces relacionándolo con la capacidad económica de los países y proponiendo líneas de acción para futuras evaluaciones y reevaluaciones de la Lista Roja de la IUCN. Siguiendo los resultados obtenidos, exploramos la situación de las evaluaciones de peces dulceacuícolas en la península Ibérica, como ejemplo de región con una gran proporción de peces amenazados con evaluaciones desfasadas. Propusimos recomendaciones basadas en el uso de técnicas moleculares para aumentar la información disponible mejorar futuras reevaluaciones de la ictiofauna ibérica de agua dulce. Como las áreas protegidas críticas son herramientas críticas de conservación, exploramos la cobertura que éstas ofrecen a las especies de peces. Para ello, identificamos los ríos más irremplazables utilizando mapas de distribución de peces dulceacuícolas, y los comparamos con la red actual de áreas protegidas, que resultó ofrecer una baja protección a los ríos irremplazables. Además, comparamos las áreas protegidas irremplazables para peces de agua dulce con aquellas que se han identificado como irremplazables para los vertebrados terrestres, encontrando discordancias que sugirieron la necesidad de reevaluar el diseño y gestión de áreas protegidas. Finalizamos esta tesis discutiendo los resultados y concluyendo con varias recomendaciones y líneas de acción para guiar la conservación de peces en los próximos años.
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    Spatial priorities for freshwater fish conservation in relation to protected areas
    (Wiley, 2023) Miranda, R. (Rafael); Miqueleiz-Legaz, I. (Imanol); Ariño-Plana, A.H. (Arturo Hugo)
    Abstract1. Freshwater habitats are vital for both humans and nature owing to theirexceptional biodiversity and valuable ecosystem services, but they are currentlyfacing serious threats. The designation and management of protected areas havebeen proposed as the most feasible way to ensure conservation objectives for thefuture. However, traditional approaches have not protected freshwater faunaeffectively, especially freshwater fish.2. Previous studies have identified the most irreplaceable terrestrial places toachieve conservation goals. Here, the aim was to investigate how the presentnetwork of protected areas preserves irreplaceable rivers for freshwater fish.3. The irreplaceability of the world's river basins was calculated using InternationalUnion for the Conservation of Nature Red List distribution maps, considering therarity, richness, and conservation status of their freshwater fish fauna. Theoverlap between irreplaceable basins and the present network of protected areaswas also calculated.4. The results highlight the conservation significance of tropical rivers, particularlythose in the Neotropics. The subset of the basins covering 30% of the mostirreplaceable land surface (in line with the United Nations 30by30 target)encompasses 99% of freshwater fish species. However, protected areas do notseem to provide sufficient protection to these basins, as 89% of their surface arealies outside protected areas. Only 7% of freshwater ecoregions meet the UnitedNations 30by30 target.5. Given the context of climate change, allocating new protected areas becomescrucial in providing better survival opportunities for freshwater fish species.Despite the limitations inherent to the absence of total knowledge of freshwaterfish biogeography and the irreplaceability index itself, this study identifies prioritysites for their conservation that may help inform decision-making in the future toestablish more effective protected areas.
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    Monitoring extinction risk and threats of the world's fishes based on the Sampled Red List Index
    (2022) Freeman, R. (Robin); Pollock, C. (Caroline); Miqueleiz-Legaz, I. (Imanol); Bohm, M. (Monika); Polidoro, B. (Beth); Carpenter, K.E. (Kent E.); Collen, B. (Ben); Miranda-Ferreiro, R. (Rafael); Sayer, C. (Catherine); Dulvy, N.K. (Nicholas K.); Hilton-Taylor, C. (Craig); Darwall, W. (William); Dewhurst-Richman, N. (Nadia)
    Global biodiversitytargets require us to identify species at risk of extinction and quantify status and trends of biodiversity. The Red List Index (RLI) tracks trends in the conservation status of entire species groups over time by monitoring changes in categories assigned to species. Here, we calculate this index for the world's fishes in 2010, using a sampled approach to the RLI based on a randomly selected sample of 1,500 species, and also present RLI splits for freshwater and marine systems separately. We further compare specific traits of a worldwide fish list to our sample to assess its representativeness. Overall, 15.1% of species in the sample were estimated to be threatened with extinction, resulting in a sampled RLI of 0.914 for all species, 0.968 in marine and 0.862 in freshwater ecosystems. Our sample showed fishing as the principal threat for marine species, and pollution by agricultural and forestry effluents for freshwater fishes. The sampled list provides a robust representation for tracking trends in the conservation status of the world's fishes, including disaggregated sampled indices for marine and freshwater fish. Reassessment and backcasting of this index is urgent to check the achievement of the commitments proposed in global biodiversity targets.
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    European water frame directive ecoregions do not adequately represent freshwater fish biogeography
    (Elsevier B.V., 2024) Miranda, R. (Rafael); Miqueleiz-Legaz, I. (Imanol); Cancellario, T. (Tommaso)
    The quest to understand species’ distribution patterns and delineate their limits has led to the establishment of the world’s ecoregions, large units of land containing a distinct assemblage of species, both for terrestrial and marine ecosystems. However, freshwaters constitute their own special case within terrestrial ecosystems, and have only recently been divided into freshwater ecoregions, primarily based on watershed limits. Freshwater ecoregions used by the European Water Frame Directive (WFD), which guides freshwater management policies in the European Union, have been criticized for not adequately representing freshwater fish biogeography. This study compares the geographic agreement between WFD ecoregions and freshwater fish distribution at the European scale. Using IUCN Red List distribution maps, we determined the composition of freshwater fish communities in major European basins. Then, we calculated a similarity matrix in order to cluster freshwater basins with more related fish assemblages. We compare our findings with WFD ecoregions and global ecoregions from the Freshwater Ecoregions of the World (FEOW) database. Our results reveal that WFD ecoregions do not sufficiently capture freshwater fish assemblage differences across Europe. Mediterranean basins exhibit high freshwater fish endemism and greater species variation, whereas central European basins harbor more similar fauna. Overall, our results align more with those of FEOW. To enhance the relevance of freshwater ecoregions in Europe for management and conservation, we propose several measures to ensure a comprehensive study involving all stakeholders in the process of defining these ecoregions accurately.
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    Presence of invasive alien species (IAS) in impounded waters of Navarre (Spain) using multi-mesh gillnets
    (2022) Miqueleiz-Legaz, I. (Imanol); Moncada, G. (Gonzalo); Baquero-Martin, E. (Enrique); Tobes, I. (Ibon); Ruiz-de-la-Cuesta, I. (Ignacio); Torrens, J. (Julen); Miranda, E. (Enrique); Miranda-Ferreiro, R. (Rafael); Escribano-Compains, N. (Nora); Escudero, J. (Javier)
    The introduction of invasive alien species (IAS) is a severe problem in ecosystems worldwide, heavily impacting biodiversity and especially endemic species. This situation is especially worrying in the Iberian Peninsula, since Spain and Portugal¿s rivers and lakes host an outstanding richness of endemic freshwater species. Ignorance about IAS presence and distribution is a serious problem that hampers its management. Regarding invasive fish species, difficulties in sampling and studying the ichthyofauna of lentic and deep waters, where many IAS inhabit, comprise some of the reasons for this lack of knowledge. In this study, we sampled the fish community of ten impounded waters in Navarre (Ebro River Basin, Spain) using multi-mesh gillnets. Four sampling points were dams located in rivers, and the remaining points were ponds. One of these ponds had a direct connection with a water channel, and another was found in a flood plain, so it connects with a nearby river in floods. The remaining ponds did not have a direct connection to any major river. A total of 14 fish species were detected (9 of which were IAS (64.3%)), with 3383 specimens collected (56% IAS). Only one of the analyzed dams did not contain IAS. Numerically, the most abundant fish was the exotic bleak (Alburnus alburnus) (almost 44% of the captures), followed by the native Ebro nase (Parachondrostoma miegii) (23.4%).
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    From expert to data-driven biodiversity knowledge: assessing ecosystem irreplaceability with IUCN red list data for freshwater fish
    (2019) Miqueleiz-Legaz, I. (Imanol); Miranda-Ferreiro, R. (Rafael); Ariño-Plana, A.H. (Arturo Hugo)
    Critical as they are for humans and nature, freshwater ecosystems are threatened-but the extent and depth of these threats are not well understood, especially if essential biodiversity data are lacking. Any policy aimed at protecting such ecosystems must first assess the threat factors and the potential harm, well before proposing conservation measures such as the creation and development of Protected Areas (PAs). These assessments must be done using a deep and sound knowledge of the actual and potential biodiversity variables. Freshwater ecosystems have been largely neglected in traditional PA design and management (Abell et al. 2007), be it for scarcity of biodiversity data, or for more perception-related reasons such as visibility and accessibility driving the allocation of conservation resources to more data-rich environments.