Ronaldo Sousa

Ronaldo Sousa
University of Minho · Department of Biology

PhD
Aquatic Ecology and Conservation. Biological invasions.

About

218
Publications
95,319
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Introduction
Ronaldo Sousa has broad interests in aquatic ecology and conservation combining empirical and theoretical approaches. Research topics include biological invasions, biodiversity and ecosystem functioning, ecosystem engineering, impacts of extreme climatic events and applied conservation mainly using invertebrates as surrogate species.
Additional affiliations
January 2000 - December 2009

Publications

Publications (218)
Article
Resource pulses are episodes of low frequency, large magnitude and short duration that result in increased resource availability in space and time, with consequences for food web dynamics. Studies assessing the importance of resource pulses by invasive alien species in the interface between terrestrial and aquatic ecosystems are rare, especially th...
Article
Full-text available
Study of the impacts of biological invasions, a pervasive component of global change, has generated remarkable understanding of the mechanisms and consequences of the spread of introduced populations. The growing field of invasion science, poised at a crossroads where ecology, social sciences, resource management, and public perception meet, is inc...
Article
Several non-indigenous bivalve species have been colonising aquatic ecosystems worldwide, in some cases with great ecological and economic impacts. In this paper, we focus on the ecosystem engineering attributes of non-indigenous invasive bivalves (i.e., the capacities of these organisms to directly or indirectly affect the availability of resource...
Article
Full-text available
Pseudunio auricularius (Spengler, 1793) is one of the most threatened unionid species worldwide. Translocation is considered one of the ultimate actions that can save this species from extinction in the Iberian Peninsula. Since 2013, massive mortalities have been recorded in the Canal Imperial de Aragón (CIA), an anthropogenic habitat where the hig...
Article
Full-text available
Climate change is expected to alter impacts of invasive alien species (IAS). As omnivores and ectotherms, invasive crayfish species (ICS) can be particularly influenced by altered thermal regimes with possible impacts on native species and key ecosystem processes, such as leaf-litter breakdown. We performed a controlled study using a multi-trophic...
Article
Full-text available
Identification of ecosystem services, i.e. the contributions that ecosystems make to human well-being, has proven instrumental in galvanising public and political support for safeguarding biodiversity and its benefits to people. Here we synthe-sise the global evidence on ecosystem services provided and disrupted by freshwater bivalves, a heterogeno...
Article
Full-text available
Taxonomic and aesthetic biases permeate biodiversity conservation. We used the LIFE program-the European Union's funding scheme for the environment-to explore the economic dimension of biases in species-and habitat-level conservation. Between 1992 and 2020, animal species received three times more funding than plants. Within plants, species at nort...
Article
The freshwater pearl mussel Margaritifera margaritifera has been suffering major population declines in Europe. This endangered species is a host specialist and exclusively requires salmonid species (Salmo trutta and Salmo salar) to complete its life cycle. In theory, obligatory biotic interactions should deserve special conservation attention, bec...
Article
Full-text available
Corbicula fluminea is a known aquatic invasive species responsible for several ecological and economic impacts. In Portugal, it is found in all major watersheds, although to varying degrees of invasion (regarding density, biomass and spatial distribution). The aim of this study was to evaluate the spatio-temporal differences in condition indices (C...
Article
Invasive alien species (IAS) are leading to the homogenisation of taxonomic and functional biodiversity, with negative consequences for key ecosystem processes in fresh water. Invasive signal crayfish (Pacifastacus leniusculus) is expected to disrupt detritus‐based food webs by affecting leaf breakdown and/or by decreasing invertebrate density and...
Book
Full-text available
The X Iberian Symposium on the Hydrographic Minho River Basin, organized by the Aquamuseu do Rio Minho/Câmara Municipal de Vila Nova de Cerveira and co-organized by the Interdisciplinary Centre of Marine and Environmental Research (CIIMAR) - University of Porto, in a multidisciplinary context, addressed themes that covered areas from the geochemist...
Article
O X Simpósio Ibérico Sobre a Bacia Hidrográfica do Rio Minho, organizado pelo Aquamuseu do Rio Minho/Câmara Municipal de Vila Nova de Cerveira e co-organizado pelo Centro Interdisciplinar de Investigação Marinha e Ambiental – Universidade do Porto, num contexto multidisciplinar, abordou temas que abrangeram áreas desde a geoquímica de sedimentos e...
Article
1. Pseudunio marocanus (Pallary, 1918) is an endemic species of Morocco and is considered one of the world's 100 most threatened species. The life cycle of this critically endangered freshwater mussel remains unknown. However, knowledge about the discharge period of its larvae and its ecological fish hosts is crucial to adopt more effective conserv...
Conference Paper
Full-text available
The Asian clam (Corbicula spp.) was first detected in 2004 in the Ebro River (Aragón, Spain). In 2006, it was also found in the Canal Imperial de Aragón (CIA) and in 2007 in the Canal de Tauste (CT). Both artificial canals held large populations of native freshwater mussels and are the main habitat of Pseudunio auricularius (Spengler 1793). However...
Article
Full-text available
Theidentification of key biodiversity areas (KBA) was initiated by the International Union for Conservation of Nature in 2004 to overcome taxonomic biases in the selection of important areas for conservation, including freshwater ecosystems. Since then, several KBAs have been identified mainly based on the presence of trigger species (i.e., species...
Conference Paper
Full-text available
Pseudunio auricularius is one of the most threatened freshwater mussel species worldwide and is classified as Critically Endangered in the IUCN Red List. The artificial Canal Imperial de Aragón (CIA) in the Ebro basin (Aragón-Spain) presents the largest census colony in the world (around 6000 tagged specimens), but since 2013 it has suffered a shar...
Article
Full-text available
Droughts can change the distribution and alter the behaviour, phenology and physiology of many species, leading in extreme cases to high mortalities or even extirpation. In this study, a before/after comparison was performed in two Portuguese river basins (Rabaçal and Tuela) to assess the possible effects of an extreme drought on the abundance and...
Article
Full-text available
Populations of the critically endangered freshwater mussel Pseudunio auricularius (Spengler, 1793) have been suffering sharp declines, particularly in the Ebro basin (Iberian Peninsula). Among other factors, pollution could be responsible for these declines. We conducted, for the first time, acute toxicological tests (96 h) with heavy metals and am...
Article
Full-text available
Molluscs are among the most diverse and widespread animal groups in freshwater habitats. Unfortunately, like most freshwater taxa, they are decreasing dramatically and are now among the most threatened animals on Earth, with many species already extinct or on the brink of extinction. Here, we review our current knowledge on the biodiversity and con...
Article
• Freshwater mussels (Order Unionida) are highly threatened. Interspecific competition for food sources with invasive alien species is considered to be one of the factors responsible for their decline because successful invaders are expected to have wider trophic niches and more flexible feeding strategies than their native counterparts. • In this...
Article
Anthropogenic freshwater habitats may provide undervalued prospects for long‐term conservation as part of species conservation planning. This fundamental, but overlooked, issue requires attention considering the pace that humans have been altering natural freshwater ecosystems and the accelerated levels of biodiversity decline in recent decades. We...
Article
Full-text available
The morphological plasticity of bivalve species may impair their correct identification. Pisidium species (Sphaeriidae) are difficult to distinguish, notably the common pea clam, Pisidium ca-sertanum (Poli, 1791), which is a polymorphic species, often misidentified and confused with other Pisidium species. This is especially true since this species...
Article
• Freshwater ecosystems are essential to human well‐being and most have high biodiversity. However, this biodiversity has been suffering severe declines owing to the expansion of human activities. Protected areas (PAs) are essential for biodiversity conservation and have proved to be successful in stopping species extirpation if managed properly. U...
Chapter
Although biodiversity is considered a value to be protected to avoid the degradation of ecosystem functions, conservation practices ignore the role of many species. Species are not protected according to their degree of risk, but according to their degree of attractiveness. The so-called iconic species are used as flag species to convince the publi...
Article
The Unionidae represent an excellent model taxon for unravelling the drivers of freshwater diversity, but, phylogeographic studies on Southeast Asian taxa are hampered by lack of a comprehensive phylogeny and mutation rates for this fauna. We present complete female- (F) and male-type (M) mitogenomes of four genera of the Southeast Asian clade Cont...
Article
Full-text available
Through the Habitats Directive (92/43/EEC) and the financial investments of the LIFE projects, Europe has become an experimental arena for biological conservation. With an estimated annual budget of €20 billion, the EU Biodiversity Strategy for 2030 has set an ambitious goal of classifying 30% of its land and sea territory as Protected Areas and en...
Article
Full-text available
A simple and low-cost method of monitoring and collecting particulate matter detaching from (or interacting with) aquatic animals is described using a novel device based on an airlift pump principle applied to floating cages. The efficiency of the technique in particle collection is demonstrated using polyethylene microspheres interacting with a cy...
Article
Full-text available
The number of non-native freshwater fishes in the Iberian Peninsula has been greatly increasing. In this study, individuals of the genus Phoxinus were detected in 18 out of 138 stream sites sampled across the Douro Basin in 2017 and 2018. A total of 26 individuals were barcoded using partial cytochrome c oxidase subunit I (COI) and cytochrome b (cy...
Preprint
Full-text available
Through the Habitats Directive (92/43/EEC) and the LIFE projects financial investments, Europe has been the world experimental arena for biological conservation. With an estimated budget of 20 billion euro/year, the EU Biodiversity Strategy for 2030 has set an ambitious goal of reaching 30% Protected Areas and ensure no deterioration in conservatio...
Article
Meiofauna organisms play an important role in ecological, trophic and sedimentary processes in estuarine ecosystems. Recently, the application of environmental DNA (eDNA) for investigating meiofauna in different environments, improved the accessibility to its diversity and composition in a scale, frequency and depth previously unattainable. Neverth...
Article
European freshwater pearl mussel (Margaritifera margaritifera) populations are declining despite a growing effort to conserve them. Here we used a combination of local ecological knowledge (LEK) and field sampling to assess past and current distribution and conservation status of this endangered species in Cávado and Neiva Rivers (Portugal). We per...
Article
Populations of the critically endangered freshwater mussel Pseudunio auricularius (Spengler, 1793) have been suffering sharp declines, particularly in the Ebro basin (Iberian Peninsula). Among other factors, pollution could be responsible for these declines. We conducted, for the first time, acute toxicological tests (96 h) with heavy metals and am...
Poster
Full-text available
El objetivo de este estudio fue analizar por primera vez la sensibilidad de M. auricularia frente a diferentes metales llevando a cabo ensayos toxicológicos agudos (96h) siguiendo las directrices de la ASTM International Standard Guide y utilizando para ello agua dura reconstituida (160-180 mg CaCO3).
Article
1. Coextinction is the simplest form of secondary extinction and freshwater mussels (Bivalvia, Unionida) may be particularly prone to this phenomenon as their life cycle includes an obligatory parasitic larval stage on fish hosts. 2. The main aims of this study were to determine the possible ecological fish hosts of Anodonta anatina (Linnaeus, 175...
Article
Meiofaunal organisms play a key role in estuarine ecosystems, being responsible for significant ecological processes. However, meiofauna constitutes a particularly difficult community to be monitored through conventional morphology-based approaches. New emerging tools, such as DNA metabarcoding, facilitate the access to these communities and provid...
Article
Full-text available
Using a new fossil-calibrated mitogenome-based approach, we identified macroevolutionary shifts in mitochondrial gene order among the freshwater mussels (Unionoidea). We show that the early Mesozoic divergence of the two Unionoidea clades, Margaritiferidae and Unionidae, was accompanied by a synchronous split in the gene arrangement in the female m...
Article
Freshwater mussels are undergoing rapid global declines due to habitat loss and fragmentation, but little is known about the effects of small hydropower plants. Here we assessed the impact of small hydropower plants on the abundance and size structure of the imperilled pearl mussel Margaritifera margaritifera. For this, we sampled 66 sites in three...
Article
Full-text available
We report for the first time that the freshwater mussel Microcondylaea bonellii (Férussac, 1827) functions as a suitable host for the European bitterling Rhodeus amarus (Bloch, 1782). Given the recent expansion of R. amarus in Europe, the possible physiological cost (e.g. competition for oxygen, reduction in water circulation, and consequent impair...
Article
Due to their sensitivity and dramatic declines, freshwater mussels are prime targets for conservation and environmental monitoring. For this, however, information is needed on life history and ecological traits, which is lacking in many taxa, including threatened species. Species recently described or recognized as valid are of particular concern,...
Article
Full-text available
1. The life cycle of Unio foucauldianus Pallary, 1936, a critically endangered freshwater mussel species (Bivalvia: Unionida), includes a parasitic phase using fish as hosts. Therefore, to develop more efficient conservation strategies it is essential to know which are the suitable fish hosts of U. foucauldianus. 2. In this study, two approaches we...
Conference Paper
Meiobenthic organisms are key components of estuarine environments, providing invaluable functions and services. In particular, meiofaunal organisms participate actively in nutrient cycles and energy flux, supporting higher trophic levels, as well as the stabilization of sediments. Due to their small size (between 30 µm and 1mm) and high dispersal...
Article
Full-text available
Mass mortality events, the rapid, catastrophic die-off of organisms, have recently been recognized as important events in controlling population size, but are difficult to quantify given their infrequency. These events can lead to large inputs of animal carcasses into aquatic ecosystems, which can have ecosystem scale impacts. Invasive freshwater b...
Article
Margaritifera auricularia is one of the most endangered freshwater mussels (Bivalvia, Unionida) in the world. Since 2013, the abundance of this species in the Ebro River basin (Spain) has sharply declined, driving the species to the verge of regional extinction. Therefore, any management measures that might facilitate the recovery of this species w...
Article
Anthropogenic habitats may function as a refuge for some species, including freshwater mussels (Bivalvia, Unionida). In this study we assessed possible differences in density, size and condition index of the Moroccan freshwater pearl mussel Pseudunio marocanus (Pallary, 1918), formerly Margaritifera marocana, colonizing an-thropogenic (sāqya = irri...
Article
Fluxes of organic matter (OM) from terrestrial ecosystems subsidize stream food webs, which support the production of ecologically and economically important species such as the sea lamprey Petromyzon marinus. Debris have been previously observed in the gut contents of sea lamprey ammocoetes, but their origin and/or the nutritional sources assimila...
Article
Anthropogenic habitats may serve as a refuge for aquatic species, including freshwater mussels (Bivalvia, Unionida). Evaluating the role of anthropogenic habitats is a fundamental, but still ignored, conservation issue given the pace that humans have been converting natural ecosystems. In this study, possible differences in abundance, size and cond...
Conference Paper
https://doi.org/10.1139/gen-2019-0083 Genome, 2019, 62(6): 372 Background: DNA metabarcoding provides a practical approach to investigate communities hard to track through traditional morphological approaches as, for instance, the estuarine meiofauna. In this study, we examined the patterns of small-scale spatial variation of meiofaunal communiti...
Article
Bivalve shells can persist over a geological time, acting as important physical resources to the associated fauna. However, few studies have investigated their relevance as persistent long-term ecological attributes to the ecosystem. As such, it is relevant to investigate the shell decays in riverine systems subjected to different environmental con...
Chapter
The Portuguese coast is located in a biogeographic transition zone, between temperate and subtropical waters where the northern or southern distribution limits of many species are found. Portuguese coastline is characterized by specific hydrographical features with a cooler northern region affected by both upwelling and rainfall leading to higher v...
Article
Full-text available
The complete mitogenomes of one (M-)ale (North America), one Hermaphroditic (Europe), and two (F-)emale (North America and Europe) individuals of the freshwater pearl mussel Margaritifera margaritifera were sequenced. The M-type and F-type (Female and Hermaphroditic) mitogenomes have 17,421 and 16,122 nucleotides, respectively. All with the same co...
Article
Freshwater mussels (Bivalvia, Unionida) are one of the most imperilled faunal groups globally, being the introduction of invasive species a possible major mechanism of threat. The Asian clam Corbicula fluminea is a problematic invasive species in aquatic ecosystems and can impair the survival of parasitic larvae (glochidia) of native freshwater mus...
Article
The freshwater pearl mussel Margaritifera margaritifera is a highly threatened species in Europe. Several mechanisms may be responsible for the decline in distribution and abundance of European pearl mussel populations, but almost no quantitative data exists about the possible negative impacts of invasive alien species (IAS). In this study, we clea...
Article
Freshwater mussels are declining globally, and effective conservation requires prioritizing research and actions to identify and mitigate threats impacting mussel species. Conservation priorities vary widely, ranging from preventing imminent extinction to maintaining abundant populations. Here, we develop a portfolio of priority research topics for...
Article
We present the most updated list of non-native freshwater fauna established in Portugal, including the Azores and Madeira archipelagos. This list includes 67 species at national level but corresponds to 84 species records, of which 53 are in the mainland, 23 in the Azores and 8 in Madeira archipelagos. We also discuss the progression of the cumulat...
Presentation
Full-text available
Margaritifera auricularia is one of the 200 species of unionids assessed in the IUCN Red List, being listed as critically endangered. The population of the Ebro basin (Spain) has suffered a strong reduction in recent years, registering very high mortalities of adult specimens, especially those found in the Canal Imperial de Aragón. Different hypoth...
Article
Full-text available
The impact of invasive alien species (IAS) on an ecosystem is primarily studied at the species level, whereas the functional impacts of their genetic and phenotypic traits are poorly investigated. We used two laboratory based experiments to assess how intrapopulation phenotypic traits (size, sex, and num- ber of claws) of the invasive red swamp cra...
Article
We present the most updated list of non-native freshwater fauna established in Portugal, including the Azores and Madeira archipelagos. This list includes 67 species at national level but corresponds to 84 species records, of which 53 are in the mainland, 23 in the Azores and 8 in Madeira archipelagos. We also discuss the progression of the cumulat...