Determination and modeling of spatial patterns of brown trout (salmo trutta linnaeus, 1758) in the Deva-Cares catchment: the role of connectivity and the niche

RESUMEN: El objetivo general de la Tesis Doctoral es determinar los patrones espaciales de la trucha común en la red fluvial de la cuenca del río Deva-Cares (norte de España) y analizar los diferentes roles que la conectividad y el nicho tienen en la determinación de la variabilidad espacial de las poblaciones de la trucha común. Los Capítulos III a VI conforman el núcleo central de esta Tesis Doctoral. En el Capítulo III, se presenta una metodología para clasificar todos los segmentos de una red fluvial como temporales o permanentes. En el Capítulo IV, se explora el rol que desempeñan las variables de nicho a diferentes escalas espaciales para determinar los patrones espaciales de densidad de la trucha común a nivel de red fluvial para cada una de las clases de edad analizadas (alevín, juvenil y adulto). También se considera el papel de la distancia hidrológica y Euclidea y la presencia de barreras impermeables para explicar los patrones de densidad espacial de la trucha común. En el capítulo V, se desarrolla un modelo numérico metapoblacional para estimar la distribución espacial de las densidades de trucha común de las tres clases de edad para toda la red fluvial en función de la topología, la conectividad y la dinámica poblacional. En el Capítulo VI, se exploran las consecuencias genéticas de la alteración de la conectividad en una población nativa de trucha común en la cuenca del río Deva-Cares. Tanto la conectividad espacial como las variables ambientales (i.e. conectividad-dispersión versus nicho) tienen un papel fundamental en la determinación de los patrones espaciales de la trucha común en la cuenca del río Deva-Cares.ABSTRACT: The general objective of this PhD Thesis is to determine the spatial patterns of brown trout in the Deva-Cares river network (Northern Spain) and to analyze the different roles that connectivity and the niche have on determining the spatial variability of this brown trout population. Chapter III to VI conform the core of this PhD Thesis. In Chapter III, a statistically-based methodology to classify river segments as temporary or perennial is presented for a whole river network. In Chapter IV, the role that niche variables at different spatial scales are playing on determining spatial density patterns of brown trout for each age-class (young-of-the-year, juveniles and adults) at a whole river network scale was explored. The role of hydrological and Euclidean distance, and the presence of impermeable barriers on explaining brown trout spatial density patterns was also considered. In chapter V, a numerical metapopulation model was developed to estimate the spatial distribution of the brown trout densities of three age-classes to the whole river network based on topology, connectivity and population dynamics. In Chapter VI, the genetic consequences of altered connectivity on a native brown trout population in the Deva-Cares catchment was explored. Both the spatial connectivity and environmental variables (i.e. connectivity-dispersal versus niche concepts) have shown to be important on determining the spatial patterns of brown trout in the Deva-Cares catchment.Agradecer al Instituto de Hidráulica Ambiental de la Universidad de Cantabria la confianza que tuvieron en mí para llevar a cabo la Tesis y poder formar parte de este gran equipo de trabajo. Al Ministerio de Economía y Competitividad por su financiación a través de las Ayudas para contratos predoctorales para la formación de doctores (BES-2013-065770) asociada al proyecto RIVERLANDS: Efectos del legado del uso del suelo en los procesos fluviales: implicaciones para la gestión integrada de cuenca (BIA2012-33572). Agradecer también la financiación de la estancia de investigación a través de las Ayudas a la movilidad predoctoral para la realización de estancias breves en centros de I+D españoles y extranjeros (EEBB-I-15-10186)

Management and conservation of fish populations in mountain streams: An holistic approach in the framework of LIFE DIVAQUA project

Producción CientíficaThe recovery of threatened and endangered fish species is among the highest priorities for biodiversity conservation in national parks and fisheries management in nearby areas. Threats to fish populations are numerous and include habitat fragmentation and degradation, proliferation of invasive and pathogen species, and climate change. Moreover, mountain areas often share the most critical threats. However, there does not exist a common strategy that integrates conservation and management plans for fish populations in mountain areas. In this regard, LIFE DIVAQUA designed a conservation strategy that integrates new knowledge gained from scientific research and long-term monitoring data, and considers the main threats to fish populations in mountain areas: (1) A long term monitoring program has been already implemented for 10 years, revealing temporal trends of fish populations in mountain streams. (2) Modeling of fish population by the use of environmental DNA allowed analyzing fish distributions in areas with scarce data and evaluating habitat suitability maps. (3) Fishways construction and removal of river barriers substantially increased the distribution area of endangered species. (4) The analysis of climate change effects in water temperature and hydrology led to the implementation of environmental flows under a climate change scenario; (5) Monitoring fish diseases, their occurrence, and temporal changes (e.g., Aeromonas spp.) can be used as an early warning signal of ecosystem unbalance. A pilot study for the implementation of this conservation and management plan in the LIFE DIVAQUA project is showing promising results. However, the success of conservation and management strategies requires a broader approach. This includes the participation of a wide range of partners and stakeholders and utilizes independent scientific oversight, assessment, and project adjustments to ensure conservation goals are met.Comisión Europea - (grant LIFE18 NAT/ES/000121

Cuencas Virtuales: bases para el diseño de un sistema nacional de monitoreo de recursos hídricos

El Uruguay transita cambios en el uso del suelo, la utilización de bienes y servicios provistos por la naturaleza, así como en los sistemas de gestión y gobernanza asociados. La expansión e intensificación de la agricultura y de las explotaciones forestales, junto a la intensificación ganadera durante los últimos 15 años, han condicionado importantes desafíos en la gestión del agua. Simultáneamente, la gestión de los recursos acuáticos procura superar la fragmentación en el análisis y toma de decisiones, avanzando hacia modelos más integrales, con mayor capacidad de aprendizaje y manejo de la incertidumbre. En este contexto, el proyecto procuró fortalecer los procesos de análisis y toma de decisión a través de la recopilación y construcción de bases de datos sobre atributos hidrológicos y de calidad del agua de estaciones de mues- treos localizados en el territorio nacional, así como diversas características de las cuencas de drenaje asociadas (tamaño de las cuencas, topografía, red de tributarios, tipo y usos del suelo, cobertura de pastizales y formaciones boscosas, vertidos puntuales, entre otros). Mediante la combinación de la teledetección, sistemas de información geográfico y técnicas estadísticas se identificaron los principales factores naturales y de origen antrópico que condicionan las diferencias espaciales observadas en atributos claves tanto de cantidad como de calidad. En este proceso se relevaron las principales fortalezas y debilidades del sistema de monitoreo actual, así como posibles estrategias de fortalecimiento en un escenario de cooperación interinstitucional e internivel de gobierno, combinando estrategias de descentralización y centralización, fomentando una estructura en red de capacidades de monitoreo, fiscalización y contralor distribuidas en el territorio. Los aportes del proyecto son insumos para un proceso de co-diseño de estrategias a definir en la red de actores del sistema actual de gobernanza del agua, proceso que se encuentra en pleno desarrollo.Agencia Nacional de Investigación e Innovació

Patterns of genetic diversity of brown trout in a northern Spanish catchment linked to structural connectivity

The alteration of structural connectivity in fluvial networks is important for the genetic dynamics of aquatic species. Exploring the effects of network fragmentation through genetic analysis is crucial to assess the conservation status of riverine species. In this study, we investigated the genetic consequences of the altered connectivity of brown trout in the Deva-Cares catchment (northern Spain). We investigated (1) genetic diversity, (2) genetic differentiation and genetic structure, (3) migration rates and effective population size and (4) genetic differentiation and riverscape characteristics. Analysis of the genetic variation among 197 individuals from the 13 study sites revealed a high degree of genetic differentiation (FsT≃ 0.181). Belowbarrier study sites had higher genetic diversity and lower FsT values, while headwater and above-barrier study sites had lower genetic diversity and higher FsT values. Most of the genetic groups identified were separated by one or more impermeable barriers. We reported an abrupt decrease in genetic diversity and effective population size in upper course tributaries and isolated reaches. Likewise, a downstream-biased gene flow was found, and it was most likely related to the fragmentation caused by barriers, since the results from migration indicated that gene flow between groups without impermeable barriers was higher bidirectionally. Isolation by impermeable barriers played a more important role than hydrological distance in determining the genetic structure. Most of the genetic groups showed small effective population sizes. Genetic analysis at the river network scale provides evidence for the role of barriers in determining genetic diversity patterns, highlighting the importance of maintaining and restoring river longitudinal connectivity.Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature. This study was partly funded by the Spanish Ministry of Economy and Competitiveness as part of the RIVERLANDS project (Ref: BIA-2012–33572). AMGF was supported by a predoctoral research grant (Ref: BES-2013–065770) from the Spanish Ministry of Economy and Competitiveness

Data from: Drivers of spatio-temporal patterns of salinity in Spanish rivers: a nationwide assessment

The salinization of freshwaters is a global water quality problem that leads to the biological degradation of aquatic ecosystems. However, little is known about the spatial extent of freshwater salinization and the relative contribution of each human activity (e.g. agriculture, urbanization, mining or shale-gas extraction). Here, we investigated environmental factors that explain spatio-temporal patterns of water salinity and examined the causes, the extent and the degree of salinization of Spanish rivers. Results showed a strong variation in water salinity among river typologies and between river reaches in good and poor ecological status according to the Water Framework Directive. The variation in water salinity was largely explained by a combination of natural (i.e. climate and geology) and anthropogenic (i.e. land use) factors. By contrast, land use factors as urbanization and agriculture were the main drivers of salinization, which affected more than one quarter of the rivers and streams in Spain, especially those in the most arid regions (central and southern regions) and in the main courses of the largest rivers such as the Ebro, Douro and Tajo rivers. The information provided here can be relevant to set priority regions and actions to ameliorate freshwater salinization

Cuencas Virtuales: bases para el diseño de un sistema nacional de monitoreo de recursos hídricos

El Uruguay transita cambios en el uso del suelo, la utilización de bienes y servicios provistos por la naturaleza, así como en los sistemas de gestión y gobernanza asociados. La expansión e intensificación de la agricultura y de las explotaciones forestales, junto a la intensificación ganadera durante los últimos 15 años, han condicionado importantes desafíos en la gestión del agua. Simultáneamente, la gestión de los recursos acuáticos procura superar la fragmentación en el análisis y toma de decisiones, avanzando hacia modelos más integrales, con mayor capacidad de aprendizaje y manejo de la incertidumbre. En este contexto, el proyecto procuró fortalecer los procesos de análisis y toma de decisión a través de la recopilación y construcción de bases de datos sobre atributos hidrológicos y de calidad del agua de estaciones de mues- treos localizados en el territorio nacional, así como diversas características de las cuencas de drenaje asociadas (tamaño de las cuencas, topografía, red de tributarios, tipo y usos del suelo, cobertura de pastizales y formaciones boscosas, vertidos puntuales, entre otros). Mediante la combinación de la teledetección, sistemas de información geográfico y técnicas estadísticas se identificaron los principales factores naturales y de origen antrópico que condicionan las diferencias espaciales observadas en atributos claves tanto de cantidad como de calidad. En este proceso se relevaron las principales fortalezas y debilidades del sistema de monitoreo actual, así como posibles estrategias de fortalecimiento en un escenario de cooperación interinstitucional e internivel de gobierno, combinando estrategias de descentralización y centralización, fomentando una estructura en red de capacidades de monitoreo, fiscalización y contralor distribuidas en el territorio. Los aportes del proyecto son insumos para un proceso de co-diseño de estrategias a definir en la red de actores del sistema actual de gobernanza del agua, proceso que se encuentra en pleno desarrollo.Agencia Nacional de Investigación e Innovació

Tackling climate change impacts on biodiversity towards integrative conservation in Atlantic landscapes

International audienc

Aquatic connectivity: challenges and solutions in a changing climate.

Publication status: PublishedFunder: Government of Cantabria, Fénix ProgrammeFunder: Christ's College, University of Cambridge, Galapagos Islands Fund; doi: http://dx.doi.org/10.13039/501100000590Funder: Fisheries and Oceans Canada, Freshwater Habitat Initiative; doi: http://dx.doi.org/10.13039/501100000041The challenge of managing aquatic connectivity in a changing climate is exacerbated in the presence of additional anthropogenic stressors, social factors, and economic drivers. Here we discuss these issues in the context of structural and functional connectivity for aquatic biodiversity, specifically fish, in both the freshwater and marine realms. We posit that adaptive management strategies that consider shifting baselines and the socio-ecological implications of climate change will be required to achieve management objectives. The role of renewable energy expansion, particularly hydropower, is critically examined for its impact on connectivity. We advocate for strategic spatial planning that incorporates nature-positive solutions, ensuring climate mitigation efforts are harmonized with biodiversity conservation. We underscore the urgency of integrating robust scientific modelling with stakeholder values to define clear, adaptive management objectives. Finally, we call for innovative monitoring and predictive decision-making tools to navigate the uncertainties inherent in a changing climate, with the goal of ensuring the resilience and sustainability of aquatic ecosystems

Impacts of diffuse urban stressors on stream benthic communities and ecosystem functioning: A review

Catchment urbanisation results in urban streams being exposed to a multitude of stressors. Notably, stressors originating from diffuse sources have received less attention than stressors originating from point sources. Here, advances related to diffuse urban stressors and their consequences for stream benthic communities are summarised by reviewing 92 articles. Based on the search criteria, the number of articles dealing with diffuse urban stressors in streams has been increasing, and most of them focused on North America, Europe, and China. Land use was the most common measure used to characterize diffuse stressor sources in urban streams (70.7 % of the articles characterised land use), and chemical stressors (inorganic nutrients, xenobiotics, metals, and water properties, including pH and conductivity) were more frequently reported than physical or biological stressors. A total of 53.3 % of the articles addressed the impact of urban stressors on macroinvertebrates, while 35.9 % focused on bacteria, 9.8 % on fungi, and 8.7 % on algae. Regarding ecosystem functions, almost half of the articles (43.5 %) addressed changes in community dynamics, 40.3 % addressed organic matter decomposition, and 33.9 % addressed nutrient cycling. When comparing urban and non-urban streams, the reviewed studies suggest that urbanisation negatively impacts the diversity of benthic organisms, leading to shifts in community composition. These changes imply functional degradation of streams. The results of the present review summarise the knowledge gained to date and identify its main gaps to help improve our understanding of urban streams.This study has received funding from the Iberian Association of Limnology (AIL) through the project URBIFUN (Urbanization effects on the relationship between microbial biodiversity and ecosystem functioning), awarded to Míriam Colls and Ferran Romero. Authors thank as well the Basque Government (Consolidated Research Group IT951-16) and the MERLIN project 101036337 – H2020-LC-GD-2020/H2020-LC-GD-2020-3.info:eu-repo/semantics/publishedVersio