Zoltán Csabai

• Ph.D.
• Head of Department at University of Pecs

1. Daily changes in the flight activity of aquatic insects have been investigated in only a few water beetles and bugs. The diel flight periodicity of aquatic insects and the environmental factors governing it are poorly understood. 2. We found that primary aquatic insects belonging to 99 taxa (78 Coleoptera, 21 Heteroptera) fly predominantly in mi...

Dispersal flight is the most important and almost the only way for primary aquatic insects to find new water habitats. During a 30-week-long project, we monitored the flight dispersal behaviour of aquatic beetles and bugs with using highly and horizontally polarizing agricultural black plastic sheets laid onto the ground. Based on the flight data o...

Life cycle and microdistribution patterns of Cordulegaster heros, a charismatic species for nature conservation, are poorly known. Life history characteristics and multiscale habitat preferences of the larvae were followed for one year in monthly intervals by systematic samplings in eight headwaters, which resulted in data on 2562 individuals. We h...

Based on an earlier observation in the field, we hypothesized that light intensity and horizontally polarized reflected light may strongly influence the flight behaviour of night-active aquatic insects. We assumed that phototaxis and polarotaxis together have a more harmful effect on the dispersal flight of these insects than they would have separa...

The essential key to routine molecular species identification (DNA barcoding/metabarcoding) is the existence of an error-free DNA barcode reference library providing full coverage of all species. Published studies generally state the need to produce more barcodes, and control their quality, but unfortunately, the number of barcoded species is still...

Freshwater ecosystems represent an unparalleled diversity of habitats and species, but the actual distribution of many species remains obscured or incomplete. The aim of the survey was to contribute to the knowledge on the fauna of lesser-known areas and fill the gaps in the distribution maps of the species. The dataset is based on a one-year-long...

Drying river networks include non‐perennial reaches that cease to flow or dry, and drying is becoming more prevalent with ongoing climate change. Biodiversity responses to drying have been explored mostly at local scales in a few regions, such as Europe and North America, limiting our ability to predict future global scenarios of freshwater biodive...

Background Chironomidae, with over 7,300 described species, are amongst the most diverse and abundant insect families in freshwater ecosystems worldwide. Chironomids are known for their widespread distribution from various water types. The level of documentation of chironomid fauna varies considerably amongst European countries, with more comprehen...

Expertise in biodiversity research (taxonomy, faunistics, conservation with taxonomic background) appears to decline worldwide. While the “taxonomic impediment” is discussed extensively in the literature, much fewer papers focus on the identification crisis, i.e., the decreasing number of experts who can identify species, and the decline of species...

Aim To determine which riverine invertebrate traits respond consistently to anthropogenic impacts across multiple biogeographic regions. Location Europe. Time Period 1981–2021. Major Taxa Studied Riverine invertebrates. Methods We compiled a database of riverine invertebrate community time series for 673 sites across six European countries span...

Understanding the joint influence of natural disturbance, spatial connectivity and biogeography on biodiversity is essential to forecast its responses to climate change. Macroinvertebrate communities in drying river networks constitute an ideal study system to understand the interplay of these ecological processes. We analyze the taxonomic and func...

A doubt has arisen about the taxonomic status of Agabus lotti within the Agabus uliginosus species group due to morphological similarities and lack of molecular data. In this study, a comprehensive morphological and molecular analysis of specimens from Central Europe was conducted, focusing on the Hungarian population. Morphological comparisons of...

Climate and land use changes, as well as human water use and flow alterations, are causing worldwide shifts in river flow dynamics. During the last decades, low-flows, flow intermittence, and drying have increased in many regions of the world, including Europe. This trend is projected to continue and exacerbate in the future, resulting in more freq...

True flies comprise approximately one-tenth of all animal species on Earth, yet despite their prevalence and ecological significance in freshwater ecosystems, members of the insect order Diptera are frequently neglected in stream studies. This absence or inconsistency regarding Diptera in literature and taxonomic lists may leave readers with a sens...

Several theoretical models have been proposed as the underlying mechanisms behind occupancy frequency distribution (OFD) patterns. For instance, the metapopulation dynamic model predicts bimodal OFD pattern indicating the dominance of dispersal processes in structuring the assemblages, while the niche‐based model predicts unimodal right‐skewed OFD...

The fundamental value of universal nomenclatural systems in biology is that they enable unambiguous scientific communication. However, the stability of these systems is threatened by recent discussions asking for a fairer nomenclature, raising the possibility of bulk revision processes for "inappropriate" names. It is evident that such proposals co...

Freshwater macroinvertebrates are a diverse group and play key ecological roles, including accelerating nutrient cycling, filtering water, controlling primary producers, and providing food for predators. Their differences in tolerances and short generation times manifest in rapid community responses to change. Macroinvertebrate community compositio...

List of the 1543 additional coauthors. Co-authors who contributed revising translations are listed first. Then, the rest of the coauthors are listed according alphabetic order of countries/territories.

Inland navigation in Europe is proposed to increase in the coming years, being promoted as a low-carbon form of transport. However, we currently lack knowledge on how this would impact biodiversity at large scales and interact with existing stressors. Here we addressed this knowledge gap by analysing fish and macroinvertebrate community time series...

The taxonomic status of Agabus lotti within the Agabus uliginosus species group has been a subject of debate due to morphological similarities and lack of molecular data. In this study, we conducted a comprehensive morphological and molecular analysis of specimens from Central Europe, focusing on the Hungarian population. Morphological comparisons...

Transitioning from perennial to non-perennial flow regimes causes ecological shifts in aquatic communities. Aquatic macroinvertebrates deploy resistance and resilience strategies to cope with flow intermittency, crucial in rivers with long-term seasonal dry episodes. Less is known, about how these strategies support community persistence in streams...

Context Global change, including land-use change and habitat degradation, has led to a decline in biodiversity, more so in freshwater than in terrestrial ecosystems. However, the research on freshwaters lags behind terrestrial and marine studies, highlighting the need for innovative approaches to comprehend freshwater biodiversity. Objectives We i...

Standardized terminology in science is important for clarity of interpretation and communication. In invasion science – a dynamic and rapidly evolving discipline – the proliferation of technical terminology has lacked a standardized framework for its development. The result is a convoluted and inconsistent usage of terminology, with various discrep...

Humans impact terrestrial, marine and freshwater ecosystems, yet many broad-scale studies have found no systematic, negative biodiversity changes (for example, decreasing abundance or taxon richness). Here we show that mixed biodiversity responses may arise because community metrics show variable responses to anthropogenic impacts across broad spat...

The zebra mussel Dreissena polymorpha is one of the most successful, notorious, and detrimental aquatic invasive non-native species worldwide, having invaded Europe and North America while causing substantial ecological and socioeconomic impacts. Here, we investigated the spatiotemporal trends in this species' invasion success using 178 macroinvert...

Standardized terminology in science is important for clarity of interpretation and communication. In invasion science — a dynamic and quickly evolving discipline — the rapid proliferation of technical terminology has lacked a standardized framework for its language development. The result is a convoluted and inconsistent usage of terminology, with...

Freshwater navigation is expected to increase in the coming years, being promoted as a low-carbon form of transport. However, we currently lack knowledge on how this will impact biodiversity at large scales and interact with existing stressors. We addressed this knowledge gap by analyzing fish and macroinvertebrate community time series spanning th...

Non-native species introductions have been acknowledged as one of the main drivers of freshwater biodiversity decline worldwide, compromising provided ecosystem services and functioning. Despite growing introduction numbers of non-native species, their impacts in conjunction with anthropogenic stressors remain poorly documented. To fill this gap, w...

Owing to a long history of anthropogenic pressures, freshwater ecosystems are among the most vulnerable to biodiversity loss¹. Mitigation measures, including wastewater treatment and hydromorphological restoration, have aimed to improve environmental quality and foster the recovery of freshwater biodiversity². Here, using 1,816 time series of fresh...

The use of long-term datasets is crucial in ecology because it provides a comprehensive understanding of natural fluctuations, changes in ecosystems over extended periods of time, and robust comparisons across geographical scales. This information is critical in detecting and analysing trends and patterns in species populations, community dynamics,...

Several theoretical models have been proposed as the underlying mechanisms behind occupancy frequency distribution (OFD) patterns. For instance, the metapopulation dynamic model predicts bimodal OFD pattern indicating the dominance of dispersal processes in structuring the assemblages, while the niche-based model predicts unimodal right-skewed OFD...

Intermittent rivers and ephemeral streams are the world's dominant type of river ecosystem and are becoming more common because of global change. However, the inclusion of intermittent rivers and ephemeral streams in water policies and management plans remains largely limited because monitoring schemes and tools are designed for perennial rivers. I...

As alien invasive species are a key driver of biodiversity loss, understanding patterns of rapidly changing global species compositions depends upon knowledge of invasive species population dynamics and trends at large scales. Within this context, the Ponto-Caspian region is among the most notable donor regions for aquatic invasive species in Europ...

The aim of our study was to compare the richness and composition of macroinvertebrate assemblages in natural reed and artificial rip-rap habitats in a shallow lake 50+ years after shoreline modifications. Lake Balaton (Hungary) provided a unique study system as approximately half of its shoreline (c.105 km) has been modified. Littoral macroinverteb...

In riverine ecosystems the species distribution, determined primarily by their environment often shows zonation patterns that are also typical in the case of net-spinning caddisfly larvae (Trichoptera: Hydropsychidae). In the present research, we aimed to build an ensemble of base learner machine learning (ML) models based on the most important env...

We outline a 100% georeferenced dataset of aquatic macroinvertebrate occurrence records collected from the operational area of the Körös-Maros National Park Directorate (SE Hungary) between 2012 and 2021. The species-level dataset includes 25,935 recordsof 644 taxa from 625 localities of wide variety of freshwater habitats from soda pans to lowland...

Ongoing climate change and rising water demands are resulting in the increasingly frequent occurrence of stream drying, particularly in smaller streams in humid temperate climates. These streams are often situated in outlying regions with insuffcient wastewater treatment management leading to inconsistent inputs of nutrients into receiving water sy...

Aim Invasive alien species are a growing problem worldwide due to their ecological, economic and human health impacts. The “killer shrimp” Dikerogammarus villosus is a notorious invasive alien amphipod from the Ponto‐Caspian region that has invaded many fresh and brackish waters across Europe. Understandings of large‐scale population dynamics of hi...

As alien invasive species are a key driver of biodiversity loss, understanding patterns of rapidly changing global species compositions depends upon knowledge of biological invasion dynamics and trends. The Ponto-Caspian region is among the most notable donor regions for aquatic invasive species in Europe. Using macroinvertebrate time series collec...

Globalization has led to the introduction of thousands of alien species worldwide. With growing impacts by invasive species, understanding the invasion process remains critical for predicting adverse effects and informing efficient management. Theoretically, invasion dynamics have been assumed to follow an “invasion curve” (S-shaped curve of availa...

Climate change is putting increasing pressure on flowing waters. Drastic water level fluctuations in rivers or drying up of small and medium-sized streams all contribute to the biodiversity crisis threatening freshwater ecosystems. Benthic diatoms are important elements of biofilm in small streams. However, knowledge on the relationship between ben...

River networks are among Earth’s most threatened hot-spots of biodiversity and provide key ecosystem services (e.g., supply drinking water and food, climate regulation) essential to sustaining human well-being. Climate change and increased human water use are causing more rivers and streams to dry, with devastating impacts on biodiversity and ecosy...

Rivers are dynamic ecosystems in which both human impacts and climate‐driven drying events are increasingly common. These anthropogenic and natural stressors interact to influence the biodiversity and functioning of river ecosystems. Disentangling ecological responses to these interacting stressors is necessary to guide management actions that supp...

With ongoing climate change and increasing water resource pressures, the knowledge and predictability of stream drying is essential for water management. However, the hydrological data for assessing the flow regime of temporary streams are often non-existent or scarce. The flow regime strongly affects stream ecological functioning and ecosystem pro...

The aim of this review is to summarize the literature knowledge about how abiotic environmental factors and biotic interactions affect the sequentially overlapping longitudinal distribution of Central European species of the net-spinning freshwater caddisfly larvae of the genus Hydropsyche (Trichoptera: Hydropsychidae). In this relation, several ph...

The Asian clam (Corbicula fluminea) is one of the rapidly spreading, very successful aquatic invasive species, which has become established widely in many parts of the world. Its spread is assumed to be by both passive and active dispersal. However, the importance of active pedal movement in dispersal is hardly known. Since there was no direct evid...

Natural floodplains are rapidly disappearing ecosystems worldwide, primarily due to changing hydrology. Continental Croatia harbours some of the largest remaining and best preserved natural riverine floodplains in Europe. To establish conservation priorities, we surveyed water beetle assemblages in three large floodplains situated in the Danube, Dr...

We present the results of the first-ever DNA barcoding study of odonates from the Maltese Islands. In total, ten morphologically identified species were collected during a two-week long expedition in 2018. Eighty cytochrome c oxidase subunit I (COI) barcodes were obtained from the collected specimens. Intra- and interspecific distances ranged from...

Stream macroinvertebrates, as non-target organisms, may face with either a single or a complex stressor during a restoration treatment. We quantified the structural, phylogenetic, and functional responses to both single (water retention) and complex (water retention and grazing) stressors and analysed how the ecological quality changes, in order to...

Intermittent rivers are prevalent in many countries across Europe, but little is known about the temporal evolution of intermittence and its relationship with climate variability. Trend analysis of the annual and seasonal number of zero-flow days, the maximum duration of dry spells and the mean date of the zero-flow events is performed on a databas...

Dispersal is an essential process in population and community dynamics, but is difficult to measure in the field. In freshwater ecosystems, information on biological traits related to organisms' morphology, life history and behaviour provides useful dispersal proxies, but information remains scattered or unpublished for many taxa. We compiled infor...

• In case of dryings, the hyporheic zone is one of the most important refugia for stream macroinvertebrate communities, including the few Odonata species living in these habitats, such as Cordulegaster species. There is no information on the desiccation resistance strategies and methods of any members of the genus, including Cordulegaster heros. •...

Studying Intermittent Rivers and Ephemeral Streams (IRES) requires regular observations of streamflow. Unfortunately, intermittent streams are poorly monitored, particularly in temperate climates. To fill gaps in knowledge of the dynamics of intermittent streams, a pilot initiative within the SMIRES project (Datry et al., 2017, https://www.smires.e...

Motivation: Dispersal is an essential process in population and community dynamics but is difficult to measure in the field. In freshwater systems, relevant information on the dispersal of many taxa remains scattered or unpublished, and biological traits related to organisms morphology, life history and behaviour offer useful dispersal proxies. We...

The river Danube is the backbone of the 'southern invasion corridor', one of the most important passages for the spread of Ponto-Caspian invaders in Europe. However, not all of these species used the passive or active upstream movement in the main channel to reach the upper sections and tributaries, some found detours. Mass occurrences of the Ponto...

Owing to their limited geographical distribution and unique ecological characteristics , Pannonian salt marshes and soda pans are considered among the most vulnerable aquatic habitats in Europe. Despite the unique nature of the soda pans and adjacent wetlands, little is known about their aquatic macroinvertebrate fauna, and there is a shortfall in...

Effective identification of species using short DNA fragments (DNA barcoding and DNA metabarcoding)requires reliable sequence reference libraries of known taxa. Both taxonomically comprehensive coverage and content quality are important for sufficient accuracy. For aquatic ecosystems in Europe, reliable barcode reference libraries are particularly...

Effective identification of species using short DNA fragments (DNA barcoding and DNA metabarcoding) requires reliable sequence reference libraries of known taxa. Both taxonomically comprehensive coverage and content quality are important for sufficient accuracy. For aquatic ecosystems in Europe, reliable barcode reference libraries are particularly...

Due to the untouched and almost pristine conditions of the Drava region, to date 438 species belonging to various aquatic macroinvertebrate animal groups have been recorded from the Drava and its floodplain. Therefore the aquatic fauna of this area is among the richest in Hungary. The most unique species of the Drava is the caddisfly Platyphylax fr...

(The paper is in Hungarian with English abstract, published in Crisicum journal) The Fehér-tó is one of the most important astatic soda pans in the Carpathian basin. The pond is separated by a dam to eastern and western basins, which are different in hydrological regime and extension of macrovegetation. In 2015 physico-chemical parameters were meas...

Taxonomic and functional patterns of macroinvertebrate communities were investigated to reveal the importance of different habitat units within a marsh system in maintaining its macroinvertebrate diversity. Hydrogeomorphic units based on their functional characteristics were used to distinguish 3 types of aquatic habitats within the marsh system: (...

The Romanian fauna comprises two species of Aquarius Schellenberg, 1800, eight species of Gerris Fabricius, 1794 and one species of Limnoporus Stål, 1868, and we hereby update the distribution and provide insights on the phenology and ecology of all eleven species in this country. We furthermore update the distribution of the two closely related sp...

Intermittent rivers and ephemeral streams (IRES) are common across Europe and dominate some Mediterranean river networks. In all climate zones, IRES support high biodiversity and provide ecosystem services. As dynamic ecosystems that transition between flowing, pool, and dry states, IRES are typically poorly represented in biomonitoring programmes...

More than half of the global river network is composed of intermittent rivers and ephemeral streams (IRES), which are expanding in response to climate change and increasing water demands. After years of obscurity, the science of IRES has bloomed recently and it is being recognised that IRES support a unique and high biodiversity, provide essential...

Detailed new records of 101 aquatic beetle taxa from 179 sites of Rhodes, Crete and Corfu Islands were given. Further species which were only known from these islands based on publication data and database records were also listed. Regarding the eight discussed families, 11, 16 and 18 species were recorded for the first time, and the number of wate...

We examined how two native co-occurring gammarids (Gammarus fossarum Koch, 1836 and G. roeselii Gervais, 1835) are distributed among microhabitats, depending on their sympatric or allopatric distribution. Under near pristine circumstances, in cases of single species occurrences, no microhabitat preference was found in G. fossarum, whereas G. roesel...

Although the influence of invasive species on the distribution of native species is well-studied, our knowledge on the processes driving the co-occurrence of native gammarid species is limited. We studied the co-occurrence of two common European gammarids, Gammarus fossarum and Gammarus roeselii, along a stream continuum in Mecsek Mountains, SW Hun...

A comprehensive survey on aquatic and semiaquatic bugs (Heteroptera: Nepomorpha and Gerromorpha) of three Greek holiday islands, Rhodes, Crete and Corfu, was conducted from 2007 to 2010 at 237 localities. In this paper, hundreds of detailed records for 30 taxa in nine families are given. The occurrences of Rhagovelia infernalis africana Lundblad, 1...

The protection, preservation and restoration of aquatic ecosystems and their functions are of global importance. For European states it became legally binding mainly through the EU-Water Framework Directive (WFD). In order to assess the ecological status of a given water body, aquatic biodiversity data are obtained and compared to a reference water...

The Ugrai-rét is one of the most diversified and most precious protected areas of the Kis-Sárrét (Körös-Maros National Park), but so far, its aquatic macroinvertebrate fauna was poorly studied, and only 107 species have been known. In this study, our aim was to explore the aquatic macroinvertebrate fauna in detail. Thorough faunistical samplings we...

2nd Central European Symposium for Aquatic Macroinvertebrate Research (CESAMIR) between 3 and 8 July 2016 at the University of Pécs, Pécs, SW Hungary. http://cesamir.ttk.pte.hu/

Records of the predaceous diving beetles of the genus Eretes Laporte, 1833 (Coleoptera: Dytiscidae) in Central Europe are summarised. While old records from the beginning of the twentieth century from the Czech Republic, Hungary, and Romania belong to Eretes griseus (Fabricius, 1781), a species which has not been recaptured in Central Europe for ne...

In odonates, the emergence behaviour and finding suitable substrates for successful molting may influence the next generation and ultimately can determine the survival of the entire population. Understanding emergence behavior of endangered species and those granted special conservation status is particularly important. Despite this, little is know...

The Kis-Sárrét is one of the most diversified and most precious protected areas of the Körös–Maros National Park, but so far, our knowledge about its aquatic macroinvertebrate fauna was far from exhaustive, and only 163 species have been known. In this study, our aim was to explore the aquatic macroinvertebrate fauna in detail and to compile the an...

In 2013 faunistical investigations were carried out three times at 24 sampling points spread over the territory of an alkaline temporary wetland in the protected area of Szabadkígyós (Körös–Maros National Park), called Nagy-gyöp. 883 new faunistic records of 155 aquatic macroinvertebrate taxa are given. New occurrence data of protected and/or red l...