Zlatko Mihaljević

• PhD
• Professor (Full) at University of Zagreb

Context Floodplains play an important role in regulating regional water and nutrient cycles in riverscapes, also supporting high biodiversity. However, ecological requirements of aquatic macroinvertebrates in such habitats are still not sufficiently studied. Aims We analysed mayfly assemblages in two habitat types (near natural and anthropogenicall...

This study focused on the aquatic insect orders that serve as biological indicators. Ephemeroptera, Plecoptera, Trichoptera, Coleoptera, and Odonata were studied with their relationships to physical, chemical, hydrological and morphological variables in 14 streams on three Croatian mountains: Papuk, Medvednica and Psunj. From 675 samples collected...

Reservoirs serve functional purposes such as irrigation and power generation. However, concerns are raised due to the alterations of the connected riverine ecosystems. Chironomidae (Diptera), a diverse aquatic macroinvertebrate group, are vital to the functioning of ecosystems and serve as water quality indicators. Their holometabolous development...

The delicate balance of aquatic environments and communities living in them is closely linked to water quality, making its assessment a crucial factor in environmental management. Despite the progress driven by the European Water Framework Directive, challenges remain, especially in understanding and addressing the specificities of rare freshwater...

Floodplains are heterogeneous systems adjacent to large rivers periodically flooded by water originating from the river’s lateral flow. During floods, the water flows into the surrounding channels, ponds and lakes, creating an integrated dynamic system characterized by a mosaic of lotic and lentic habitats and by the exchange of nutrients and inhab...

Hydromorphological degradation is one of the most common stressors to freshwater ecosystems nowadays. Rivers lose riparian vegetation, habitat heterogeneity, natural flow velocity, etc., due to hydromorphological alterations. We analyzed macroinvertebrate communities in a wide range of hydromorphological conditions – from near natural sites to sign...

Simple Summary Chironomids or non-biting midges, which are a diverse group of insects, can be found in various freshwater habitats. Plitvice Lakes National Park in Croatia, known for its rich freshwater environment, is an ideal location for studying these insects in the long term. Our study aimed to uncover the types of chironomids present, underst...

According to the first Croatian check-list (Čerba et al. 2020), a total of 239 Chironomidae species has so far been recorded from the country. In the present paper we report the finding of two new taxa from the mountain stream Šumetlica, eastern Croatia, namely Boreoheptagyia legeri (Goetghebuer, 1933) and Diamesa cf. insignipes Kieffer, 1908. Šume...

Global climate change is expected to exacerbate extreme discharge events in freshwater ecosystems as a consequence of changes in precipitation volume and snow cover duration. Chironomid midges were used as a model organism in this study because of their small size and short life cycles, which enable fast colonization of new habitats and great resil...

Water mites are the most diverse freshwater group of Acari and despite growing research interest in the ecology of this group, the environmental influences along longitudinal river gradients on their assemblages are still not fully understood. The objective of this study was to determine how physico-chemical water properties and hydromorphological...

Here we present the results of a mayfly study conducted on a hydromorphologically altered lowland river in Croatia, the Bednja River. Twenty-two mayfly species were recorded, Baetis fuscatus (Linnaeus, 1761) and Serratella ignita (Poda, 1761) being the most widespread and Paraleptophlebia submarginata (Stephens, 1836) and Cloeon dipterum (Linnaeus,...

Lotic freshwater ecosystems are among the most threatened ecosystems worldwide due to the effects of multiple stressors, such as intensive land use in their catchments, morphological alterations, flow regulation, pollution, and climate change. Odonata are often used as valuable indicators of ecological integrity and anthropogenic disturbance of fre...

European lowland rivers are extensively impacted by hydromorphological pressures, and the relationship between individual benthic macroinvertebrate groups and these degradations are insufficiently investigated. Therefore, we studied distribution and ecological traits of Odonata inhabiting a lotic system in the Pannonian lowland ecoregion (ER 11) in...

Simple Summary The majority of European lowland rivers are under the impact of multiple stressors (water quality, hydromorphological alterations, land-use), however, the consequences of these influences on mayflies have not been sufficiently studied. Therefore, we studied mayfly assemblages and their relationship to environmental factors along a mi...

1. Riparian zones are vital areas of interaction between land and rivers and are often degraded by several pressures such as urbanisation, intensive agriculture and river engineering works. 2. This policy brief provides five key policy messages and recommendations to be considered by policy-makers, scientists, managers, and stakeholders to enhance...

Although intermittent rivers are present in all climate regions, their biodiversity and ecosystem functions were largely overlooked in the past. Recently, considerable effort has been made to improve our understanding of these, however, many data gaps still remain. We conducted a study to improve knowledge of the community patterns and processes in...

Under the EU Water Framework Directive, ecological assessment and management are based on type-specific reference conditions. In the EU it may be difficult to find sites in large rivers with at least near-natural conditions, though this is not the case in southeast Europe, where stretches of large rivers still exist with at least near-natural condi...

Here we present a first record of Baetis vardarensis Ikonomov, 1962 in Croatian freshwater habitats. The species was collected in February and March 2020 at two sites in the Sava River. With this record, Croatian mayfly species richness increased to a total of 85 species. In addition, one of the species previously known only from literature, Kagero...

The freshwater polychaete Hypania invalida is indigenous to the Ponto-Caspian region. The transfer of the species from the Black Sea to most of Europe was mainly via the Danube River, and its distribution increased rapidly after the opening of the Rhine-Main-Danube Canal in 1992. The presence of this species may influence the relationships of other...

Hydromorphological alterations are among the most widespread anthropogenic pressures in rivers andstreams. They comprise channelization, damming, water abstraction etc. resulting in habitats alteration and subsequentchanges in aquatic community composition. Aim of this study was to test to what extent hydromorphologicalalterations influence aquatic...

Increasing human pressures have a negative impact on freshwater habitats and their biota worldwide. To protect habitats and the species contained within them, ecological assessments over a gradient of near natural to degraded freshwater habitats are essential. Odonata assemblages were investigated at 46 study sites in Croatia encompassing slightly...

Freshwater ecosystems are endangered worldwide by various human pressures, resulting in dramatic habitat and species loss. Many aquatic invertebrates respond to disturbances in their habitat, and mayflies are among the most sensitive ones. Therefore, we investigated mayfly response to anthropogenic disturbances at 46 study sites encompassing slight...

Chironomid identification for freshwater bioassessment purposes is rarely finer than family or subfamily level. This has led to their taxonomic neglect and a lack of knowledge about their characteristics and ecology at the genus or species level, which in turn makes their implementation in bioassessment models even less appealing. The aim of this s...

The family of non-biting midges (Diptera, Chironomidae) represent one of the most common and abundant group in freshwaters, inhabiting a wide variety of habitats and ecological niches. Although there is a long tradition of limnological research in Croatia, to date no extensive species list has been made for this insect family. Thus, we summarized t...

Many studies have reported a negative impact of freshwater habitat modification on biota. Nevertheless, some man-made water bodies have proven to be valuable for biodiversity conservation as they can harbour many species. We investigated 36 man-made water bodies to determine their suitability as habitats for Odonata. Larvae were sampled in littoral...

Studies on aquatic Diptera in the Plitvice Lakes National Park (Croatia) conducted in the last 50 years have produced 157 species and 7 taxa of aquatic Diptera placed in 13 families. Samples were collected at 25 sampling sites representing the four main types of karst aquatic habitats: spring, stream, tufa barriers and lakes. All records of all the...

Predicting anthropogenic actions resulting in undesirable changes in aquatic systems is crucial for the development of effective and sustainable water management strategies. Due to the co-occurrence of stressors and a lack of appropriate data, the effects on large rivers are difficult to elucidate. To overcome this problem, we developed a partial c...

The freshwater oligochaete Branchiura sowerbyi is indigenous to southeast Asia, but can be found inhabiting most of Europe. This tubificid was even described for the first time outside of its natural area of occurrence: in the garden of the Royal Botanic Society in London. It has spread over all continents except Antarctica, and in Europe it has be...

Predation is a biotic interaction that links water mites to different taxonomic groups of benthic invertebrates. Diptera larvae (Chironomidae) and microcrustaceans (Cladocera, Copepoda, Ostracoda) are known to be the most commonly preferred prey by water mites. Although these predatory interactions are known from observations and ex situ investigat...

Water mites are predators on microcrustations (Copepoda, Cladocera, Ostracoda) and insect larvae (mostly Diptera). Their communities usually have great diversity with high species richness but relatively low abundance. This may have important implications for poorly investigated predator-prey interactions of water mites in natural habitats. A subla...

Man-made freshwater habitats have been widely used to successfully modify the environment for human benefit, including purposes of irrigation, flood control or electricity generation. Over the past decade, our knowledge about the mayfly fauna and its ecology in South-East Europe has been growing, yet the data related to lentic assemblages remain ve...

Stoneflies are among the most sensitive aquatic insect taxa and therefore arguably the best indicator of the excellent, i.e. pristine, ecological status of surface streams. Karst habitats are one of the most exciting freshwater habitats in terms of biological-geological interplay. They, in turn, support a biodiversity far superior to surrounding fr...

Even though alderflies, as well as many other aquatic macroinvertebrates, are widely used as indicators of freshwater quality, the knowledge of their distribution, biology and ecology in karst freshwater habitats is still very scarce. Aiming to fill this gap, we investigated alderfly assemblages along an oligotrophic karst hydrosystem. Sampling was...

Research examining mayfly ecology in karst streams and rivers has increased in recent years, though microhabitat preferences remain poorly characterized. We examined mayfly assemblage taxonomy, functional feeding groups and microhabitat preferences in two contrasting lotic Dinaric karst catchments, one pristine and one anthropogenically impacted. A...

Despite increasing numbers of studies on aquatic insects in South-East European streams, there are still gaps in the knowledge about their distribution and assemblage composition in many regions. As one of the most abundant and sensitive aquatic insects, mayflies are widely used as bioindicator taxa. With the main goal of improving the knowledge of...

Mayfly emergence was studied in the Plitvice Lakes National Park (Croatia) monthly over a 2-year period in four habitats (springs, streams, mountainous rivers, tufa barriers) using monthly collections of emergence traps. A total of 12 mayfly taxa were recorded. Almost half of the collected specimens belonged to the genus Baetis Leach, 1815, which w...

Remarkably, unlike other parts of Europe, the ecology of mayflies in the southeastern regions is still poorly known. Here we present the first comprehensive study of Ephemeroptera in the tufa-depositing habitats of the Dinaric Karst. The study was conducted in Plitvice Lakes National Park monthly during a one-year period (2007–2008) in different ty...

Mayfly ecological traits are studied in relation to diverse type of habitats.

Ecology is a science that studies the mutual interactions between organisms and their environment. The fundamental subject of interest in ecology is the individual. Topics of interest to ecologists include the diversity, distribution and number of particular organisms, as well as cooperation and competition between organisms, both within and among...

A total of 12 dragonfly species were recorded at Vlačine Reservoir in the Dinaric Western Balkan region (ER 5) in Croatia. Habitat conditions, i.e. vegetation structure and physico-chemical water properties of the reservoir, are presented and discussed. Habitat conditions were suitable for life cycle completion of Mediterranean species such as Lind...

Mayflies are one of the most important orders of freshwater inhabiting insects and they are widely used in ecological studies. Mayfly ecology and distribution in the Mediterranean part of the Western Balkans are insufficiently investigated. Our study encompassed 9 sampling sites along the course of the Cetina River, the longest Mediterrranean river...

The influences of river regulations on aquatic biota are insufficiently investigated. We assessed the level of ecological disturbance of the mayfly assemblages through the damming and flow alterations at two highly regulated Mediterranean rivers in Croatia: the Cetina River and its tributary, the Ruda. Contrary to our hypotheses, species richness,...

Knowledge of the mayfly biodiversity in the Balkan Peninsula is still far from complete. Compared to the neighbouring countries, the mayfly fauna in Croatia is very poorly known. Situated at the crossroads of central and Mediterranean Europe and the Balkan Peninsula, Croatia is divided into two ecoregions: Dinaric western Balkan and Pannonian lowla...

Springs are stable environments with constant abiotic factors and therefore of use in variety of ecologicalexperiments. We investigated the influence of canopy coverage on abundance, diversity, phenology andfeeding guilds among Diptera assemblages at two rheocrene karst springs located near each other. Thesprings differed by canopy coverage while p...

The mayfly fauna of Plitvice Lakes NP was investigated at 14 sampling sites representing different types of karstic freshwater habitat (springs, streams, tufa barriers and lakes). Specimens were sampled from February 2007 to February 2009 using different methods and 19 taxa were identified. Lotic habitats supported more mayfly species than lentic h...

Knjiga koju držite u rukama nastala je suradnjom genetičara i ekologa (evolucija se nametnula sama od sebe kao nužno polje ispreplitanja osnovnih genetičkih i ekoloških saznanja). Budući da smo i jedni i drugi biolozi po svojem osnovnom pozivu, nije nam bilo teško usuglasiti vlastite poglede na modernu biologiju. A to je upravo ono što je izdavačka...

The aim of our study was to investigate how exposure to heavy metal-rich waters from gypsum mining affects the morphology and levels of primary DNA damage in Gammarus balcanicus. Chemical analysis revealed increased concentrations of metals in water and sediment collected at a site impacted by gypsum mine wastewaters. The specimens also showed elev...

Adult aquatic dance flies (Empididae) were collected during July 2012 and July 2013 in Montenegro using sweep nets and by aspirator at 21 sampling sites. From 25 species recorded in this study, 22 species are new to the fauna of Montenegro: Chelifera pyrenaica Vaillant, Hemerodromia laudatoria Collin, Clinocera stagnalis (Haliday), Clinocera wesmae...

Man-made activities such as mining generate certain amounts of metal contaminated wastes which can reach aquatic environment and cause the serious effects on different organisms and ecosystem. Chemical analysis of the environmental samples is the most direct approach to reveal their pollution status but it cannot always provide information on biolo...

Emergence patterns of blackflies (Diptera: Simuliidae) were investigated for 2 years at nine sites in the Plitvice Lakes area of Croatia, using pyramid-type traps. A total of 38 012 specimens representing 10 haematophagous species were collected. The dominant species was Simulium angustipes Edwards, 1915, a vector transmitting avian trypanosomes. W...

The aim of this study was to determine which environmental factors influence emergence of insects at two contrasting habitats: one with constant and one with variable water temperature. We hypothesized that emergence of holometabolous insects is triggered by water temperature where temperature variations occur, while light is the main stimulus for...

True flies (Diptera, Insecta) are one of the most important groups of aquatic insects in respect of the number of families and abundance of individuals. The goals of this study were to determine emergence patterns and the main ecological factors that influence dipteran family abundance and emergence at barrage lake outlets. Differences in abundance...

True flies (Diptera, Insecta) are one of the most important groups of aquatic insects in respect of the number of families and abundance of individuals. The goals of this study were to determine emergence patterns and the main ecological factors that influence dipteran family abundance and emergence at barrage lake outlets. Differences in abundance...

The caddisfly community composition in different microhabitats at tufa barriers was studied in the Plitvice Lakes NP, Croatia. Three tufa barriers were investigated and six emergence traps were installed at each site covering various microhabitats. Sampling was conducted monthly during the year 2008. Tufa barriers are lake outlet habitats, but they...

Aquatic dance flies (Empididae; Clinocerinae and Hemerodromiinae) are important components of freshwater assemblages, especially in running waters. They are predators as larvae and adults and thus essential for understanding aquatic food webs. This study was conducted in Plitvice lakes National Park (Croatia) representing a wide variety of freshwat...

Spatial and temporal trends of a phytophylous chironomid community on the submerged plant species Ceratophyllum demersum L. were investigated in a eutrophic lake (Lake Sakadaš, Danube floodplain area in Croatia) during summer 2004. The study also included an analysis of functional feeding groups (FFG) and the influence of environmental parameters o...

Caddisflies were collected in the Plitvice Lakes NP during 2008 using emergence traps at 3 locations at tufa barriers. A total of 2217 specimens, belonging to 44 species, 27 genera and 12 families were recorded during this study. Six species, Hydroptila cognata, Hydroptila occulta, Ecnomus tenellus, Potamophylax luctuosus, Beraeodes minutus and Cer...

In the period 1999-2010 biological investigations were conducted at 369 sampling stations all over Croatia, which included water-quality assessment according to benthic macroinvertebrates, involving 10 institutions. Water quality is assessed according to a type-specific approach which is demanded by the EU Water Framework Directive. From all the in...

In the period 1999–2010 biological investigations were conducted at 369 sampling stations all over Croatia, which included water-quality assessment according to benthic macroinvertebrates, involving 10 institutions. Water quality is assessed according to a type-specific approach which is demanded by the EU Water Framework Directive. From all the in...

To estimate the impacts of an Al-contaminated aquatic environment on DNA integrity in the blood cells of eastern mosquitofish Gambusia holbrooki Girard 1859 inhabiting Lake Njivice (Island of Krk, Croatia), an evaluation using the alkaline comet assay was carried out. Genome integrity was studied in parallel with the same fish species inhabiting th...

Adult aquatic dance flies were collected in the Plitvice Lakes National Park from 2005 to 2009 using various sampling methods. Sampling was done at 13 sampling sites representing four main types of karst aquatic habitats: spring, stream, tufa barriers and lakes. A total of 22 species were recorded belonging to 6 genera. Four species (Chelifera pyre...

Colonization of aquatic insect larvae was investigated in a second order woodland stream using trays filled with natural substrate. Patterns of colonization differed significantly between seasons in terms of number of taxa, density and biomass of aquatic insect assemblages. Larvae in the first (out of five) size class made up 35.5% of all colonizer...

Two gypsum karst lakes and one non-gypsum karst lake were studied for copepod and cladoceran species composition in relation to specific habitat characteristics. The investigation was conducted from March to June 2007. Four copepod and six cladoceran species were recorded. Gypsum karst lakes are characterized as sulphate lakes and they show signifi...

Lake Visovac is a karstic phenomenon in the south of Croatia. It is a travertine barrage lake situated in the river Krka. Plankton community dynamics in three hydrological different parts in the lower basin of the lake was investigated. Plankton was collected monthly in a year period. All data point out that discharge, followed by temperature and t...

In the present paper, the results of two macrozoobenthos analysis based indices (Saprobic Index and Extended Biotic Index) are used as biological indicators in the assessment of river water quality. The objective of the paper is to establish the extent to which the results of these methods are comparable. The results indicate that both indices are...

Adult aquatic dance flies were collected in the Plitvice Lakes National Park from 2005 to 2009 using various sampling methods. Sampling was done at 13 sampling sites representing four main types of karst aquatic habitats: spring, stream, tufa barriers and lakes. A total of 22 species were recorded belonging to 6 genera. Four species (Chelifera pyre...

Colonization of aquatic insect larvae was investigated in a second order woodland stream using trays filled with natural substrate. Patterns of colonization differed significantly between seasons in terms of number of taxa, density and biomass of aquatic insect assemblages. Larvae in the first (out of five) size class made up 35.5% of all colonizer...

In this pilot study, we evaluated the usefulness of the alkaline comet assay as a biomonitoring tool at the level of plankton communities affected by varying water quality. Zooplankton was collected in autumn 2007 and spring 2008 in two shallow lakes, one being predominantly polluted with aluminium compounds as result of water treatment process (La...

The first data on the population ecology and diet of the endemic ukliva dace (Telestes ukliva Heckel, 1843) are presented. Along the Cetina River system, the ukliva dace accounted for 38.4% of the overall fish fauna abundance, but only 6.4% of total fish biomass. The ukliva dace population exhibited migratory behaviour during the year and showed a...

This report describes an investigation of genotoxic effects in medicinal leech (Hirudo verbana) exposed to water and sediment of Lake Njivice (Krk Island, Croatia) contaminated by aluminium compounds. The levels of primary DNA damage in leech haemocytes and loss of DNA integrity caused by acute and chronic exposure to contaminated water and sedimen...

Twenty species of aquatic dance flies (Empididae: Clinocerinae and Hemerodromiinae) were recorded from the Cetina River system, Croatia. No previous such research has been done on any Mediterranean river concerning aquatic dance flies. Adult dance flies were sampled at 7 locations with an aspirator and sweep nets between May and September 2005 and...

Adult caddisflies were collected in altered and man-made habitats of the hydro-electric power plant system in the Drava River in spring and autumn 2006. All sampled habitats (reservoir, drainage ditches, tailrace canals and old river channel) are greatly influenced by hydro-technical management. Altogether 24 species were recorded. Five species, Hy...

Adult caddisflies were collected in altered and man-made habitats of the hydro-electric power plant system in the Drava River in spring and autumn 2006. All sampled habitats (reservoir, drainage ditches, tailrace canals and old river channel) are greatly influenced by hydro-technical management. Altogether 24 species were recorded. Five species, Hy...

MIHALJEVI, Z., Current velocity and food supply as factors affecting the composition of macroinvertebrates in bryophyte habitats in karst running water. Biologia, Bratislava, 59: 577—593, 2004; ISSN 0006-3088. In the lotic aquatic biotopes on a tufa barrage in the Plitvice cascade lake sys-tem macroinvertebrate samples associated with a calcareous...

Data are given on the water quality, vegetation and benthic macroinvertebrates in 1980/81 and 2001 in the shallow, Mediterranean lake Jezero, Krk Island, Croatia. The main refuge for macroinvertebrates changed from submerged vegetation to bare flock and flock associated with reed decay. The flock originated from a flocculation process in a water tr...

The diversity, species composition and structure of the fish community were studied in the vicinity of three power plant reservoirs in the middle part of the Drava River in Croatia. Over a period of twenty years in a collection of 25,913 fishes, 56 different fish species belonging to 16 families were recorded. The family Cobitidae is represented by...

The depth distribution of oligochaetes was studied in Visovac lake (Croatia) along a transect from 1 to a maximum of 24 metres. In the material collected, 21 oligochaete species belonging to 4 families were identified, all of them more or less common in European lakes. The greatest diversity of oligochaetes was found at a depth of 4-6 m (18 taxa)....

The copepod communities of karstic lakes along the eastern Adriatic coast were studied. Lakes were divided in several groups according to their morphology (deep, shallow, barrage and reservoirs), production (oligotrophic, mesotophic and eutrophic), and salinity of water: freshwater and brackish. Copidodiaptomus steueri, Eucyclops serrulatusand Macr...

The length, weight, sex structure and reproduction of the spined loach were observed on spined loach from the delta of the Neretva River. Maximal Tl for females was 100.4 mm and for males 63.5 mm. Lamina circularis was visible in specimens not smaller than 45.6 mm. The male: female sex structure was 1:4.4, and in some locations males were not found...

During biological research in 1995/96 of Lake Visovac in karstic Dinarid area, a large number of calanoid and cyclopoid copepods were obtained from plankton. Among these materials, the uncommon high mountain species Eudiaptomus hadzici (Brehm, 1939) was recognized. The discovery of this species in a karstic Mediterranean lake at an altitude of 32 m...

Macroinvertebrates on floating artificial substrates were studied in the Sava river during two investigation periods with an interval of nine years. The level of water pollution differed in the two periods. During each investigation, macroinvertebrat.es were collected in two seasons with low water regimes (winter, summer), but, under different temp...

Background and purpose: The Lake Vrana is a cryptodepression with a bottom 62 m below and surface 11-14 m above sea level. Situated south-west of Croatia, in the island of Cres, it has an area of 5.75 km2. The maximum depth is 76 m. Lake Vrana is warm, monomictic, with mixing between November and April, followed by stratification during the summer....