BUSCADOR RECOLECTA

Peer reviewed

Peer reviewed

Peer reviewed

The comparison of plants dispersed by endozoochory between two migratory waterbirds (gulls and storks) within the Doñana ricefields showed no community differences between species. From 21 plant taxa, eight plant species were considered weeds, four alien species and only two fleshy fruit. Endozoochory by migratory waterbirds has major implications for plant distributions in a rapidly changing world, Peer reviewed

Eutrophication is a major cause of wetland degradation worldwide. In recent decades, reductions in nutrient inputs have led to improvements in water quality in many rivers and lakes in central and northern Europe, but long-term trends are less clear in southern Europe. We conducted the first comprehensive study of water quality in Doñana (SW Spain), one of the most important wetland complexes in Europe and the Mediterranean region. The core area of Doñana is a large shallow, seasonal marsh (UNESCO World Heritage Site—WHS) that floods during rainy, cool winter months, then dries out during the summer. The marsh is fed by three main streams whose catchments are within a Biosphere Reserve but are impacted by greenhouses (for cultivating fruit, irrigated with groundwater), poorly treated urban wastewaters and tourism. From 2013 to 2016, we monitored nutrient (Total P, Total N, PO4−3, NH4+, NO3−, NO2−) and phytoplankton chlorophyll-a (chla) concentrations in surface waters of the Doñana marsh and the three main streams. We quantified changes in greenhouse cover since 1995 using satellite images. Nutrient concentrations in streams were consistently higher than in the marsh, particularly in the Partido and Rocina streams that regularly reached concentrations equivalent to a “bad physico-chemical status” under the EU Water Framework Directive (WFD), and whose catchments suffered a fivefold expansion of greenhouses from 1995 to 2016. The Partido was the most polluted stream, and the most affected by wastewater effluents, and had particularly high concentrations of NH4+ (Geometric Mean = 0.3 mg L−1) and NO2− (GM = 0.52 mg L−1) across seasons. Patterns in chla concentrations were less consistent, but streams (GM = 6.78 µg L−1) generally had higher concentrations than the marsh (GM = 4.27 µg L−1). Nutrient concentrations in spot samples within the marsh largely depended on a combination of evaporation (as revealed by higher stable isotope δ2H values in the water column) and spatial processes (concentrations increase close to stream entry points, where conductivity is lower). Anthropogenic nutrient pollution in entry streams is a serious problem in Doñana, with extensive stretches too toxic for fish. Reinforcement of policies aimed at reducing nutrient inputs to Doñana are urgently required to meet the biodiversity conservation and environmental objectives for the WHS and WFD, respectively. Paradoxically, the marsh is currently relied upon to purify the water entering from streams., Peer reviewed

1. The American brine shrimp Artemia franciscana is important in aquaculture and has become invasive in other continents, aided by dispersal via waterbirds. However, little is known about processes underlying its genetic diversity and population structure in its natural habitat in North America. These processes, including dispersal and local adaptation, are pivotal drivers of species distribution and community structure, and therefore central to aquatic biodiversity. 2. We studied 15 populations in natural saline lakes of Saskatchewan, Canada to determine the influence of variation in geological history, water chemistry, lake size and location. We aimed to determine the relative importance of isolation by distance (IBD) and isolation by environment (IBE) using the cytochrome c oxidase subunit 1 gene (CO1) as a mitochondrial marker and five nuclear microsatellite markers. 3. Geographic patterns for CO1 and microsatellites differed, with lakes clustering in different groups based on genetic distances according to the marker used. CO1 better indicated historical colonization processes, suggesting potential routes of initial colonization when lakes were formed after deglaciation 11,000-15,000 years ago. 4. Differentiation between lakes based on nuclear markers was strongly related to variation in hydrochemistry, suggested by distance-based redundancy analysis (dbRDA), but there was no indication of IBD. The ratio between alkalinity and the sum of Ca and Mg concentrations was particularly important, although a lake with a high Cl concentration caused by Potash mining also had a unique Artemia population. 5. Geochemistry is important in the adaptive radiation of anostracan crustaceans. Our study suggests it also underlies intraspecific genetic variation between populations, promoting IBE, and making dispersal ineffective when cysts are moved by birds between lakes with different hydrochemistry. This dataset was used in the following publication: Frisch, D., Lejeusne, C., Hayashi, M., Bidwell, M.T., Sánchez-Fontenla, J., Green, A.J. 2021. Brine chemistry matters: isolation by environment and by distance explain population genetic structure of Artemia franciscana in saline lakes. Freshwater Biology DOI: 10.1111/fwb.13737, Peer reviewed, This dataset was used in the following publication: Frisch, D., Lejeusne, C., Hayashi, M., Bidwell, M.T., Sánchez-Fontenla, J., Green, A.J. 2021. Brine chemistry matters: isolation by environment and by distance explain population genetic structure of Artemia franciscana in saline lakes. Freshwater Biology DOI: 10.1111/fwb.13737

: Waterbirds can transport aquatic invertebrates internally, contributing to metapopulation dynamics between aquatic habitats in a terrestrial matrix. However, research into this dispersal process to date has focused on individual field sites, or laboratory studies. We investigated the invertebrates dispersed by endozoochory by the lesser black-backed gull Larus fuscus wintering in Andalusia, south-west Spain in 2016-2017, comparing seven sites interconnected by their movements, with different degrees of anthropogenization (three landfills, two saltpan complexes, a lake and a ricefield area). In the ricefields, we also compared gulls with the larger white stork Ciconia ciconia. A total of 642 intact invertebrates and their propagules (mainly plumatellid bryozoans, cladocerans and other branchiopods) were recorded in excreta (faeces and pellets) from gulls and storks. A greater diversity and abundance of invertebrates were recorded in ricefields, notably 43 individuals of the alien snail Physa acuta. One snail was still alive in a gull pellet three weeks after being stored in a fridge. This represents the first record of snail dispersal within waterbird pellets. Viability was also confirmed for the cladoceran Macrothrix rosea recorded in ricefields, and the alien brine shrimp Artemia franciscana recorded mainly in saltpans. In ricefields, gulls and pellets had significantly fewer propagules and fewer taxa than storks and faeces respectively.Through their high mobility, gulls and storks can disperse invertebrates between different natural and artificial habitats, and even to landfills. They can promote metapopulation dynamics for native bryozoans and branchiopods, but also the spread of invasive snails and brine shrimp., Peer reviewed

1. Omnivorous waterbirds play an important role in aquatic ecosystems as dispersal vectors via direct ingestion, transportation and egestion of plant and invertebrate propagules (i.e. endozoochory). Predatory birds also have the potential to disperse plants and invertebrates that were first carried internally or externally by their prey animals. However, the potential contribution of predatory waterbird species to propagule dispersal in aquatic ecosystems remains understudied. 2. We chose the grey heron Ardea cinerea (Ardeidae) to study the potential of predatory waterbirds to disperse propagules within and among aquatic ecosystems. We hypothesized that (1) herons disperse a wide variety of plant and invertebrate propagules, from different habitats, with different morphologies (i.e. dispersal syndromes), and including both native and alien species; (2) propagules are ingested with prey species that are primary dispersal vectors (i.e., herons are secondary dispersers); (3) heron pellets show a similar abundance and richness of propagules across their widespread range. We collected 73 regurgitated heron pellets containing undigestible remains from 12 locations across the United Kingdom and The Netherlands, and examined the taxonomic diversity of plant seeds, invertebrates and prey remains. 3. Pellets were dominated by mammal hairs (99% by volume), and bones confirmed the ingestion of small mammals (prevalence of 38%, e.g. water voles Arvicola amphibius), fish (14%), and birds or amphibians (6%). A total of 266 intact plant seeds were recovered from 71% of the pellets, representing 50 taxa from 17 plant families, including the alien Cotula coronopifolia. The cumulative number of plant species dispersed was lower at higher latitudes. Eight plant species recorded had not previously been recorded as dispersed via waterbirds, and only three species have an “endozoochorous dispersal syndrome”. Plant taxa were dominated by Caryophyllaceae, Cyperaceae, Juncaceae and Poaceae, with 24 species from the littoral zone (Ellenberg moisture values of 7-12) and 21 terrestrial species (Ellenberg moisture values of 4-6). Intact invertebrate propagules were found in 30% of the pellets, dominated by Cladocera (Daphniidae) and Bryozoa (including the alien Plumatella casmiana). 4. Our results demonstrate that grey herons disperse plant seeds and aquatic invertebrates widely in north-western Europe. Herons regurgitate pellets that contain plant and invertebrate propagules from both aquatic or terrestrial habitats, for which secondary dispersal via ingestion along with prey is the likely underlying mechanism (i.e. propagules either attached to or in the digestive systems of the various prey). Our findings showcase the potential of predatory waterbirds as vectors of plants and invertebrates, and how they may facilitate connectivity between freshwater and terrestrial habitats., Peer reviewed

The dataset includes a file with information relative to blood chemistry values (16 parameters), body measurementes (2 parameters), moulting stage (3 categories), body-mass index (1 parameter) and sex (2 categories) of black-necked grebes (669 individuals) during the moulting periods (late August-early December) of 2008 and 2009 at the Odiel marshes, southwestern Spain: (i) File: Blood chemistry values and body measurements of black-necked grebes according to moulting stage and sex., The study was funded by grant P07-CVI-02700 from the Consejeria de Innovacion, Ciencia y Empresa (Junta de Andalucia)/EU-ERDF., Peer reviewed

Mapes sobre diferents tipus d’impactes en tot el Mar Mediterrani. Dades primàries (mapes) associades a un article acceptat per la revista Scientific Reports (2018). Publicat a: https://doi.org/10.1038/s41598-018-33237-w, Dades primàries (mapes) associades a un article publicat a la revista Scientific Reports, 2018, vol. 8. http://doi.org/10.1038/s41598-018-33237-w