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Periphyton communities are fundamental components of freshwater ecosystems that influence water quality, nutrient cycling, and productivity. Additionally, periphyton communities serve as valuable food sources in aquaculture. The periphyton communities on two substrates—heather mats and geotextiles—were compared in four temperate fishponds. After 51 days of immersion, the geotextiles exhibited significantly greater fluorescence, indicating a greater abundance of algae and cyanobacteria. Conversely, the abundance (and biomass) of periphyton invertebrates on heather mats was greater than that on geotextiles, and the difference became more pronounced over time. These differences resulted from significantly greater dipteran larval abundances (biomasses) on the heather mats than on the geotextiles. This study suggested that heather mats can significantly enhance food abundance and availability within the water column under Central European conditions. [ABSTRACT FROM AUTHOR]

Copyright of Ecosphere is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The browntrout Salmo trutta Linnaeus, 1758 is an important species for fisheries in Armenia,with a comparatively wide distribution in both wild habitats and aquaculture. Despite its significance and widespread presence, there is limited information regarding diseases and parasites affecting brown trout in Armenia. The aim of this study was to examine theparasite fauna of brown trout in the southern part of Armenia. The research was conducted in the Vayots Dzor Region, as well as at the Scientific Center of Zoology and Hydroecology, and Armenian National Agrarian University. Captured fish were examined using themethodof complete parasitological research. Parasites were analyzed undermicroscope and identified using specialized manuals based on their morphological features. A total of 20brown trout were captured between September and December 2023. Of these, 8 individuals (40%) were (40%) were infected with parasites. Six species of parasites were identified: Dactylogyrus vastator Nybelin, 1924 (Monogenea: Dactylogyridae),Gyrodactylussp. (Monogenea: Gyrodactylidae),Bunodera luciopercaeMüller, 1776 (Trematoda: Allocreadiidae),Proteocephalus longicollis Zeder, 1800 (Cestoda: Proteocephalidae),Khawia armeniaca Cholodkovsky, 1915 (Cestoda: Lytocestidae),and Ichthyophthirius multifiliis Fouquet, 1876 (Ciliata: Ichthyophthiriidae). Parasite infections were generally characterized by low intensity, except forI. multifiliis. Gyrodactylus sp.and B. luciopercaehelminths were detected for the first time in Armenia. This pilot study provides baseline information for further large-scale investigations and offers a valuable insightforfarmers to better understand thechallenges associated with efficient production.

Abstract The distribution–abundance relationship (DAR) is a well‐established macroecological pattern, where more locally abundant species are also more widespread across landscapes. However, it is not clear whether this relationship is temporally invariant, or how destabilization may manifest. Here, we examine the DAR at the landscape level in a unique but overlooked model system, that is, a waterbird assemblage inhabiting fishponds within the Třeboňsko Basin Biosphere Reserve, Czechia. Using 12 years of biannual census data across 134 intensively managed fishponds, collected in May and July, we describe variation in the slope of the DAR, expressed as the association between bird density and fishpond occupancy. We then tested for the role of environmental parameters and bird traits in determining the relationship's shape, utilizing general multivariate regression and a model‐averaging technique. Overall, we corroborated an expected positive DAR for waterbirds, and we present, for the first time, a consistent seasonal weakening of the interspecific DAR. We posit that this decline in the relationship's slope is a result of the deterioration and homogenization of habitat quality later in the summer, which resulted in a large deficit of suitable fishponds as populations increased. The DAR did not vary among years in either month. We also found that population trend was the most influential predictor of each species' response to changing environmental conditions; species with increasing regional abundance have stronger intraspecific DARs. Our results show that seasonal deterioration of habitat quality significantly impacts waterbird communities by altering the population spatial structure and that this is reflected in the shape of the DAR. This finding has important practical consequences, particularly in landscapes under human exploitation, where management decisions can determine ecosystem structure. Such analytical approaches can be used to pinpoint processes that are difficult to detect otherwise and thus assist conservation efforts.

Snails are the first intermediate host in the life cycle of trematodes. Previous research found that Trichopodus microlepis fish, cultured in earthen ponds in Tan Nhut Commune, Binh Chanh District, Ho Chi Minh City, Vietnam had a high infection rate with metacercariae of Centrocestus formosanus and Procevorum sp. It is necessary to investigate whether habitats supplying water to the ponds may contribute to the transmission by carrying intermediate hosts and/or cercariae into these ponds or not. A study of cercariae and snail composition in rice fields and canal supplying water directly to these Trichopodus microlepis ponds was carried out with six samplings in the years 2022 and 2023. A total of 1,151 snails were collected, and nine snail species belonging to 8 genera and 6 families were identified. Three snail species in both rice fields and canal were infected with trematode (cercariae stage) including Bithynia siamensis, Lymnaea viridis and Indoplanorbis exustus. The overall prevalence in the dry season (25.9%) was significantly higher than in the wet season (10.6%) (P<0.05). Three cercariae morphotypes were recovered from snails: xiphidio (in all three snails), echinostome (in Lymnaea viridis and Indoplanorbis exustus), and pleurolophocercous in Bithynia siamensis. This finding shows that Bithynia siamensis is one of the infected sources for Trichopodus microlepis fish cultured in ponds, as pleurolophocercous is also the cercariae in the family of Heterophyidae (including Centrocestus formosanus and Procevorum sp.). Further research should be done to clarify the transmission of fish-borne zoonotic diseases to cultured Trichopodus microlepis in other habitats including the actual fishponds, and sources of trematodes in order to produce Trichopodus microlepis free of metacercariae, contributing to clean aquaculture development and safe food for local people in the area. [ABSTRACT FROM AUTHOR]

Many marsh birds, like bitterns or rails, are endangered species inhabiting only natural habitats and dependent exclusively on different types of emergent vegetation. In a changing environment, some of these habitat specialists are becoming more flexible, shifting their preferences by colonizing man-made habitats. We studied habitat selection by Little Bitterns (Ixobrychus minutus minutus) breeding in a fishpond landscape in south-eastern Poland. Applying a large-scale research approach, we examined several habitat features in order to predict the presence of the Little Bittern from a direct comparison of areas with and without breeding birds. Partial least squares (PLS) regression identified two components of several variables that explained 53% of the variation in the presence of the Little Bittern in a fishpond habitat. The occurrence of the Little Bittern was limited to high-quality patches of emergent vegetation, the height, width and area of which were all significantly greater in the area with breeding birds than in unoccupied patches. Patches with a highly variable edge line in the form of fringes or indentations were less favoured. An optimal water level throughout the breeding season was crucial for nest-site selection and ensured access to food. The heterogeneity of the pond dykes and pond canals positively predicted the presence of the Little Bittern by creating potential nesting or foraging sites. Interestingly, the proportion of bulrushes (Typha spp.) in the emergent vegetation patches had a negative effect on the presence of the Little Bittern. The main threat to this habitat‐sensitive species was the cutting of perennial emergent vegetation, in particular the Common Reed (Phragmites australis). [ABSTRACT FROM AUTHOR]

Over the decades, the aquaculture sector has witnessed substantial growth, contributing significantly to the nation's economy. However, the menace of CyanoHABs threatens the sustainability of fish farming. Considering the possible hazards linked to cyanotoxins in food and water, a comparative study design between commercial fish in Nigeria and South Africa was employed to investigate cyanotoxins in the water from fishponds. Six commercial fishponds in Calabar Municipality—Nigeria and Duthuni—South Africa with varying climatic zones were selected. Water samples from the ponds were collected at intervals during different seasons (summer, winter, dry, and wet seasons) to capture climate-induced variation. Liquid chromatography–mass spectrometry (LCMS) in combination with the metabolites database was used for the identification of toxic cyanometabolites in water samples. The molecular networking approach, coupled with the Global Natural Products Social Molecular Networking (GNPS) database and CANOPUS annotation, enabled the putative identification of cyanometabolites. The resulting molecular network unveiled discernible clusters representing related molecule families, aiding in the identification of both known cyanotoxins and unfamiliar analogues. Furthermore, the molecular network revealed that water samples from different fishponds shared specific metabolites, including ethanesulfonic acid, pheophorbide A, cholic acid, phenylalanine, amyl amine, phosphocholine (PC), and sulfonic acid, despite variations in location, local climatic factors, and sampling sites. The fishponds in Nigeria showed the presence of multiple cyanotoxin classes in the dry, wet, and summer seasons in the water. Aflatoxin was identified in all sampling sites in Nigeria (N1, N2, and N3). The Duthuni, South Africa, sampling sites (P1, P2, and P3) exhibited the presence of microginins and microcystins. All the fishponds displayed a widespread occurrence of anabaenopeptins, aplysiatoxins, aflatoxin, microcolins, and marabmids during the selected summer. In conclusion, the untargeted metabolome analysis, guided by GNPS, proved highly effective in identifying both toxic and non-toxic metabolites in fishponds. [ABSTRACT FROM AUTHOR]

While aquaculture is increasingly considered a globally important source of protein, growing fish for human consumption is not new. Indigenous aquaculture systems, such as loko i'a (fishponds), were successfully implemented in ancient Hawai'i and represent a technological advancement designed to sustain a growing human population while maintaining—instead of supplanting—natural ecosystem function in the process of increasing food availability. Biocultural restoration efforts in Hawai'i, aimed at revitalizing Indigenous stewardship, have included restoration of loko i'a to sustainably increase the availability of local seafood. While it is clear from historical accounts that loko i'a can augment fish within estuaries, their role as a nursery ground that supplements surrounding fish populations and fisheries harvest (i.e., providing spillover) remains unstudied in the current literature. This study aimed to test the extent to which loko i'a restoration can supplement fish populations and fisheries harvest both inside the loko i'a and in the surrounding waters. A food web model was constructed representing nutrients, phytoplankton, fish, and fisheries in three distinct habitats. The model, set in Kāne'ohe Bay, O'ahu, Hawai'i, revealed that there were interactive effects of the area under loko i'a management, bay fishing effort, and fish dispersal rates on fish density and fisheries harvest. We found that increasing the area under loko i'a management not only increased loko i'a fish density and fisheries harvest but also created the potential to supplement bay fish populations and fisheries harvest under certain scenarios. We also identified a trade‐off whereby at high fish dispersal rates, a larger area under loko i'a management provided maximal benefits to the bay fish population and fisheries harvest, while at low fish dispersal rates, a smaller area under loko i'a management was more beneficial to bay fish populations and harvest. As expected, loko i'a also created a surplus of fish within the pond. Our results support the idea that restoration of Indigenous aquaculture systems can positively impact conservation efforts and food security by increasing local fish availability, through both direct production and supplementation of surrounding fish stocks. [ABSTRACT FROM AUTHOR]

This study focuses on developing an affordable IoT-based water quality monitoring system for domestic fish ponds. The system aims to enable remote monitoring of critical water parameters, offering real-time data access through mobile or web interfaces. It includes an alert system to notify the pond owners of any significant changes in water quality, allowing swift corrective action. The initiative stems from challenges faced by aquaculture farmers due to insufficient knowledge about water pH levels. Understanding pH's importance, especially within the optimal range of 6.5-9.0 for fish culture, is crucial for success. Tests conducted on the system's performance in detecting various pH levels across different pond environments demonstrated its reliability in identifying low and normal pH levels. However, anomalies were observed in detecting higher pH levels, indicating potential sensitivity limitations that need further investigation for system refinement. While the system excelled in detecting low and normal pH levels accurately, improvements are required for detecting higher pH thresholds to ensure comprehensive monitoring across diverse water conditions. This enhancement is crucial for effective fish pond management and reducing losses for aquaculture farmers.

Abstract While aquaculture is increasingly considered a globally important source of protein, growing fish for human consumption is not new. Indigenous aquaculture systems, such as loko i‘a (fishponds), were successfully implemented in ancient Hawai‘i and represent a technological advancement designed to sustain a growing human population while maintaining—instead of supplanting—natural ecosystem function in the process of increasing food availability. Biocultural restoration efforts in Hawai‘i, aimed at revitalizing Indigenous stewardship, have included restoration of loko i‘a to sustainably increase the availability of local seafood. While it is clear from historical accounts that loko i‘a can augment fish within estuaries, their role as a nursery ground that supplements surrounding fish populations and fisheries harvest (i.e., providing spillover) remains unstudied in the current literature. This study aimed to test the extent to which loko i‘a restoration can supplement fish populations and fisheries harvest both inside the loko i‘a and in the surrounding waters. A food web model was constructed representing nutrients, phytoplankton, fish, and fisheries in three distinct habitats. The model, set in Kāne‘ohe Bay, O‘ahu, Hawai‘i, revealed that there were interactive effects of the area under loko i‘a management, bay fishing effort, and fish dispersal rates on fish density and fisheries harvest. We found that increasing the area under loko i‘a management not only increased loko i‘a fish density and fisheries harvest but also created the potential to supplement bay fish populations and fisheries harvest under certain scenarios. We also identified a trade‐off whereby at high fish dispersal rates, a larger area under loko i‘a management provided maximal benefits to the bay fish population and fisheries harvest, while at low fish dispersal rates, a smaller area under loko i‘a management was more beneficial to bay fish populations and harvest. As expected, loko i‘a also created a surplus of fish within the pond. Our results support the idea that restoration of Indigenous aquaculture systems can positively impact conservation efforts and food security by increasing local fish availability, through both direct production and supplementation of surrounding fish stocks.

This study presents the findings of a faunistic survey conducted on aquatic beetles and bugs in nine protected areas in South Bohemia. For sampling, baited funnel traps, aquatic light traps, and kitchen strainers were utilised. In total, 75 beetle species from ten families and thirteen heteropteran species from nine families were identified. Additionally, eight beetle species and one hemipteran species that were found are listed in the national red list. A notable discovery was the identification of a new locality of the protected diving beetle Graphoderus bilineatus in Horní Lužnice. [ABSTRACT FROM AUTHOR]

Increasing levels of dissolved organic matter (DOM) in watercourses in the northern hemisphere are mainly due to reduced acid rain, climate change, and changes in agricultural practices. However, their impacts vary in time and space. To predict how DOM responds to changes in environmental pressures, we need to differentiate between allochthonous and autochthonous sources as well as identify anthropogenic DOM. In this study we distinguish between allochthonous, autochthonous, and anthropogenic sources of DOM in a diverse watercourse network by assessing effects of land cover on water quality and using DOM characterization tools. The main sources of DOM at the studied site are forests discharging allochthonous humic DOM, autochthonous fulvic DOM, and runoff from urban sites and fish farms with high levels of anthropogenic DOM rich in protein-like material. Specific UV absorbency (sUVa) distinguishes allochthonous DOM from autochthonous and anthropogenic DOM. Anthropogenic DOM differs from autochthonous fulvic DOM by containing elevated levels of protein-like material. DOM from fishponds is distinguished from autochthonous and sewage DOM by having high sUVa. DOM characteristics are thus valuable tools for deconvoluting the various sources of DOM, enabling water resource managers to identify anthropogenic sources of DOM and predict future trends in DOM. [ABSTRACT FROM AUTHOR]

An ever-increasing demand for protein-rich food sources combined with dwindling wild fish stocks has caused the aquaculture sector to boom in the last two decades. Although fishponds are potentially strong emitters of the greenhouse gas methane (CH4), little is known about the magnitude, pathways, and drivers of these emissions. We measured diffusive CH4 emissions at the margin and in the center of 52 freshwater fishponds in Brazil. In a subset of ponds (n = 31) we additionally quantified ebullitive CH4 fluxes and sampled water and sediment for biogeochemical analyses. Sediments (n = 20) were incubated to quantify potential CH4 production. Ebullitive CH4 emissions ranged between 0 and 477 mg m−2 d−1 and contributed substantially (median 85%) to total CH4 emissions, surpassing diffusive emissions in 81% of ponds. Diffusive CH4 emissions were higher in the center (median 11.4 mg CH4 m−2 d−1) than at the margin (median 6.1 mg CH4 m−2 d−1) in 90% of ponds. Sediment CH4 production ranged between 0 and 3.17 mg CH4 g C−1 d−1. We found no relation between sediment CH4 production and in situ emissions. Our findings suggest that dominance of CH4 ebullition over diffusion is widespread across aquaculture ponds. Management practices to minimize the carbon footprint of aquaculture production should focus on reducing sediment accumulation and CH4 ebullition.

This paper presents geospatial datasets, figures, and tables illustrating i) the location and total area of fish farms under cultivation; and ii) the spatiotemporal dynamics of reed cover in Hungarian fishponds generated from the published study of Sharma et al., [1]. Preliminary data for fish farm locations were obtained from the Institute of Agricultural Economics (AKI), followed by significant refinement based on high-resolution Google Earth Pro-imagery. The fishpond area dataset was validated against the values reported in annual statistical reports on aquaculture. In order to map reed vegetation freely available Sentinel-2 imagery (between 2017 and 2021) was accessed from the Copernicus Open Access Hub [2] and emergent macrophyte cover was classified using the NDVI-based threshold values [1]. Scientists, policymakers, and fish farmers can all benefit from such geospatial datasets. It could be used to monitor the extent of fishponds in Hungary and to design farm-level reed management plans to optimize the provision of ecological and production services.

Abstract Aim In the present study, the structure of the benthic invertebrates in ponds in the presence and absence of Nile tilapia was evaluated. Methods The benthic macroinvertebrates and physicochemical parameters were analyzed for a period of eight weeks, every 15 days, in two ponds (one with fish and the other without fish). Benthic invertebrates were sampled with artificial substrate samplers, made with cheap and common materials, like expanded clay, loofah leaves and gravel. Results With the exception of turbidity, the other physical and chemical variables of water quality were within the ideal limits for tilapia farming. Despite that, there was a significant difference for all physical-chemical parameters monitored, and the average turbidity was much higher in pond with fish. The use of artificial substrate samplers for biomonitoring was effective in the colonization of several taxa in a short period of time (15 days). For benthic community metrics, organism richness, diversity and evenness were significantly higher in the pond without fish. On the other hand, the dominance of Chironomidae and the abundance of Glossiphonidae were much higher in the pond with fish. For Chironomidae, this family was dominant in both treatments, but reached a higher frequency in the pond with fish (98.49%) than in pond without fish (92.87%). The presence of sensitive families, like Leptoceridae (Order Trichoptera), was higher in the pond with no fish, as well as the metric of Ephemeroptera, Plecoptera and Trichoptera families (% EPT). Conclusions The presence of fish altered the macrobenthic community, since metrics of richness and diversity presented lower values in pond with fish.

Two live feed relevant copepods for larval fish and shrimps, Pseudodiaptomus annandalei and Apocyclops royi, were predominant year-round in a tropical brackish fishpond system. The ponds environment is harsh concerning physicochemical properties; temperature 20–32 °C, salinity 15–23 besides abrupt salinity drops 15–9, frequent severe hypoxia, and poor nutritional seston quality. In 50 studies investigating several physiological endpoints, P. annandalei performs optimally within 18–32 °C and salinity 10–30 and A. royi within 24–32 °C and salinity 10–32. Most extreme, A. royi is reported in situ at salinity 50 and in the laboratory; it can adjust from salinity 20 to freshwater within just two generations when fed on Baker's yeast. Both species and in particular A. royi have developed an outstanding capability to convert ingested seston with poor fatty acid composition into the necessary long-chained polyunsaturated fatty acids (PUFAs) characterizing their tissues. Hence, they self-enrich their bodies' fatty acid profiles. Their physiological plasticity is likely a prerequisite for existing extensive mass production in the harsh pond environment. Moreover, A. royi exhibit additional traits, that is, high density tolerance qualifying also for intensive mass production suggesting it as the most promising live feed of the two species for fish and shrimp hatcheries. [ABSTRACT FROM AUTHOR]

Copyright of Economics & Environment / Ekonomia i Środowisko is the property of Fundacja Ekonomistow Srodowiska i Zasobow Naturalnych and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Fish farming in Serbia takes place in cyprinid (carp) and salmonid (trout) fish farms that together account for over 95% of the total fish produced. Cyprinids are grown in warm water fish farms, and cold water farms are designed for trout. The great majority (97%) of cyprinid fish farms are located in Vojvodina, Serbia’s northern province. This paper examines how the traditional carp sector was developed during the recent 20- year period in Vojvodina, paying particular attention to the comparison of the number and condition of cyprinid fish farms in that interval according to the available sources. The comparison was made by comparing maps with data on fishponds from 1999 and 2021, and according to the data from the Statistical Office of Serbia. After the analysis of many data from other authors and our study, it is evident that there is a lot of room for improving the production of cyprinid fish in Vojvodina. This is especially because we noticed decreasing trends for two major parameters: the area of fishpond water surfaces in Serbia (from 7,190 ha to 6,299 ha), and the number of ponds in Vojvodina (from 72 to 60), from 1999 to 2021, respectively. On the contrary, the amount of fish produced has increased from 2,409 t in 2002 to 4,761 t in 2021. According to government planning documents, Serbia lacks a national strategy for development of aquaculture production in general, and especially of cyprinid fish species.

Copyright of Journal of Field Ornithology is the property of Resilience Alliance and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Heron vocalization and its behavioral functions are one of the least researched aspects of heron biology. The main aim of this study was to investigate the patterns of seasonal and daily vocal output of male Little Bittern (Ixobrychus m. minutus; n = 8) during the breeding season (May–August). The advertising call started on 10th May, and finished on 28th July. The first peak of calling activity occurred between 21st May and 1st June, and the second one was between 14th June and 7th July. The daily vocal activity fluctuated and depended on the time of day. The males were most active between 0300–0900 hours and 1600–2200 hours, with the highest peaks in vocal output occurring before sunrise and before sunset. Higher vocal activity was observed in the evening compared to the morning hours. Moreover, the vocal activity of males was not related to air temperature. [ABSTRACT FROM AUTHOR]

The bird assemblages in the Levice fishponds protected area, SW Slovakia, has been analyzed. Altogether 156 bird species, of them 83 (53%) water birds (living on or around water) were found in 2018–2020. Breeding was recorded in 20 species of water birds, of which Fulica atra, Anas plathyrhynchos and Podiceps cristatus were predominant. The number of water bird species was highest in the spring (66) and lowest during the winter (18). The following species were first recorded there between 2018 and 2020: Ardeola ralloides, Hydroprogne caspia, Lymnocryptes minimus, Tringa erythropus, Podiceps auritus, Cygnus cygnus, Tadorna tadorna, Grus grus and Aquila chrysaetos. Our results supported the great importance of the Levice fishponds as a habitat of many bird species over the year, reflecting extensive management of man-made fishponds.

Abstract Background Fishing is probably one of the oldest economic activities in the history of humankind. Lakes, rivers and streams in Europe are important elements in the European landscape with a rich diversity of fish and other aquatic organisms. Artisanal fisheries have therefore been of great importance for the provision of food, but also animal feed, medicine, fertilizer and other needs. These fishermen had a deep knowledge about the waterscape and its biota. However, ethnoichthyology remains a small topic within contemporary ethnobiology in Europe. Our focus lies within northern Europe in the late medieval to modern period, but encompasses the wider area with some reference to earlier periods where informative. Method We have reviewed a large amount of literature mainly on the relationship between man and fish in freshwaters from late medieval times (defined here as the fifteenth century) until the early twenty-first century. The main focus is on freshwater (including anadromous and catadromous) fish in northern Europe, the main area of study for both authors, though examples have been included from elsewhere to indicate the widespread importance of these fisheries. The review includes studies from various fields such as archaeology, ethnography, fish biology, geography, linguistics and osteology to map what has been studied of interest in ethnoichthyology. These data have been analysed and critically reviewed. Results There are archaeozoological studies, studies of specialised fishers as well as artisanal fishing among the peasantry, research of folk taxonomies, fishing methods (including the use of poison) and gear, which are all of great interest for ethnoichthyology. There is also research on traditional preserving methods for fish as food and for other purposes. Of interest is the keeping of fish in wells, ponds and aquaria. However, there is still room for more research within many domains of ethnoichthyology. Conclusion Humans have always utilized fish and other aquatic resources. Nonetheless, few ethnobiologists working within Europe are so far researching human-fish relationships. This paper demonstrates the range of research available, but also points to future studies. It is important to widen ethnobiological research in Europe to include fish.

Communities of aquatic beetles and heteropterans were surveyed in 13 protected areas in South Bohemia. We used baited funnel traps, subaquatic light traps and a kitchen strainer for sampling. Overall, the occurrence of 84 species of aquatic beetles from 9 families and 17 species of aquatic heteropterans from 9 families were recorded in the surveyed localities. Moreover, during the survey we recorded 14 species of aquatic beetles and two species of aquatic heteropterans listed in the Red List of Endangered Species of the Czech Republic. The most interesting records are Bidessus grossepunctatus at two localities, Hydroporus scalesinaus at one locality and Notonecta lutea at three localities. Our results point to relatively high biodiversity in some protected areas and their crucial importance as refuges for these insect communities. [ABSTRACT FROM AUTHOR]

Copyright of Reti Medievali is the property of Firenze University Press and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The Asian tapeworm Khawia japonensis, a specific parasite of the common carp (Cyprinus carpio), has been found for the first time in Europe, in Italy (2010), with further records also in Slovakia (2014) and the Czech Republic (2016). In the present paper, new data on the distribution of the non-indigenous K. japonensis is presented in different countries in Central Europe (Hungary, Poland and Slovakia), including its first record in Hungary and Poland, and in the wild fish in the Laborec River (Tisa River basin) and drainage canal of the Zemplínska šírava water reservoir, in south-eastern Slovakia. The highest prevalence (47%) was recorded in a carp breeding facility in eastern Slovakia, and the highest intensity of infection (8 parasites per fish) occurs in free-living fish from the Laborec River located in the same region. The morphology of recently found K. japonensis specimens is compared with that of population from common carp in Italy and from the same fish host in Asia and North America. The first insight on pathology, including histological examination, is provided, and pathological changes induced by the scolex of K. japonensis penetrated into the intestinal villi are also described. The recent spreading of this parasite in several major European river basins (Danube, Elbe, and Vistula) indicates its high ability to establish in new regions and represents another example of anthropogenic introduction of fish pathogens. [ABSTRACT FROM AUTHOR]

Human activities in relation to aquatic ecosystems result in significant economic losses in the form of contamination of water sources, deteriorating its quality and therefore its availability in lakes, water bodies and even in soil. Hence the need for systematic revitalisation or reclamation of water ecosystems. Such actions, in order to be rational, require a detailed understanding of the causes, and then the use of appropriate technology. The need for the above-mentioned actions result from the weather changes that have been noticeable in recent years, as well as environmental pollutants increasing water eutrophication in reservoirs and stimulating the development of some species of cyanobacteria. These cyanobacteria can cause serious water poisoning, especially in water supply systems. Therefore, a rational, comprehensive technology for the removal of bottom sediments and their processing into organic and mineral fertiliser has been developed with properties similar to manure. It also creates opportunities to improve the structure of soils thanks to the supply of organic carbon, the loss of which was found, among others, in also in soils of Poland and EU. These new possibilities of revitalisation hitherto unknown make it possible to a large extent, compliance with environmental requirements when revitalising water reservoirs and soil. [ABSTRACT FROM AUTHOR]

In this study we report the results of a faunistic survey on aquatic beetles and heteropterans in 12 selected protected areas in South Bohemia. For sampling, we used baited funnel traps, subaquatic light traps, and a kitchen strainer. In total, we found 92 species of aquatic beetles from 10 families and 12 species of aquatic heteropterans from 6 families. We also found 16 species of aquatic beetles and 2 species of aquatic heteropterans listed in the national Red list including interesting records of Graphoderus bilineatus at 3 sites, Bidessus grossepunctatus at 2 sites and Hydroporus scalesianus at 1 site. [ABSTRACT FROM AUTHOR]

Artificial fishponds are assumed to be suitable alternative habitat for many waterbirds including fish-eating predators such as herons. However, fish farming may lead to contrasting consequences for birds breeding in these biotopes and act as an ecological trap. I examined nestling diet and reproductive success of the least studied heron species in Europe, the endangered Little Bittern Ixobrychus minutus, at two fishpond complexes in south-western Slovakia. A total of 95 breeding attempts by this species were recorded during 2015–2019 in the study area, 84% of which produced at least one nestling. Despite relatively high nest success at both sites, the number of fledged nestlings differed significantly between the two fishpond complexes. The observed differences were mainly caused by higher nest predation at one of the fishponds. The diet of nestlings also differed between study sites. While the food taken at fishponds that are used for intensive farming of Common Carp Cyprinus carpio contained significant proportions of insects (41%) and amphibians (14%), at fishponds used mainly for individual sport fishing, parents fed their nestlings exclusively fish. However, the total amount of food delivered to nestlings was similar at both fishpond complexes. This suggests that Little Bitterns are able to adapt to fishponds with various intensities of management. Nevertheless, considering differences in nest predation risk between studied fishponds, other factors such as abundance and structure of littoral vegetation and predator abundance, can influence the breeding success of this species in artificial fishpond habitats. Identifying such factors may be important for the conservation and management of this species. [ABSTRACT FROM AUTHOR]

Background: Fishing is probably one of the oldest economic activities in the history of humankind. Lakes, rivers and streams in Europe are important elements in the European landscape with a rich diversity of fish and other aquatic organisms. Artisanal fisheries have therefore been of great importance for the provision of food, but also animal feed, medicine, fertilizer and other needs. These fishermen had a deep knowledge about the waterscape and its biota. However, ethnoichthyology remains a small topic within contemporary ethnobiology in Europe. Our focus lies within northern Europe in the late medieval to modern period, but encompasses the wider area with some reference to earlier periods where informative. Method: We have reviewed a large amount of literature mainly on the relationship between man and fish in freshwaters from late medieval times (defined here as the fifteenth century) until the early twenty-first century. The main focus is on freshwater (including anadromous and catadromous) fish in northern Europe, the main area of study for both authors, though examples have been included from elsewhere to indicate the widespread importance of these fisheries. The review includes studies from various fields such as archaeology, ethnography, fish biology, geography, linguistics and osteology to map what has been studied of interest in ethnoichthyology. These data have been analysed and critically reviewed. Results: There are archaeozoological studies, studies of specialised fishers as well as artisanal fishing among the peasantry, research of folk taxonomies, fishing methods (including the use of poison) and gear, which are all of great interest for ethnoichthyology. There is also research on traditional preserving methods for fish as food and for other purposes. Of interest is the keeping of fish in wells, ponds and aquaria. However, there is still room for more research within many domains of ethnoichthyology. Conclusion: Humans have always utilized fish and other aquatic resources. Nonetheless, few ethnobiologists working within Europe are so far researching human-fish relationships. This paper demonstrates the range of research available, but also points to future studies. It is important to widen ethnobiological research in Europe to include fish. [ABSTRACT FROM AUTHOR]

Populations of the endangered diving beetle Graphoderus bilineatus are decreasing across Europe. Evidence‐based conservation of its local populations requires good knowledge of its habitat requirements, but data from different countries are often incomplete or contradictory.Graphoderus bilineatus was common until 1950s but then almost disappeared in the Czech Republic. Using data from a recent field survey in its core distributional area in the Czech Republic, we evaluate its habitat preferences at the habitat and microhabitat scale.We found that extensively managed fishponds can provide similarly suitable habitats for G. bilineatus as do more natural habitats including floodplain and sandpit pools, while the species is typically absent in intensively managed fishponds. All else being equal, the species is more likely found in larger water bodies surrounded by other wetlands and is more often absent at sites in agricultural landscape.We detected only weak preferences on the microhabitat scale. They suggested that G. bilineatus tends to occur in deeper water but closer to the shore and in microhabitats dominated by Glyceria or Typha. These microhabitat associations partly differ from those reported from other countries.Moreover, G. bilineatus was found at localities with higher species richness of large‐bodied aquatic beetles, both common and threatened, supporting the species status as an umbrella species for other aquatic macroinvertebrates.Our findings provide guidelines for conservation management of currently known localities and other potentially suitable sites, including the creation of new ones. Finally, our study reinforces the Annex II species status of G. bilineatus in the Habitats and Species Directive. [ABSTRACT FROM AUTHOR]

Fish farm ponds generate organic matter (OM) composed mainly of nitrogen (N) and phosphorous (P) which are usually released by the effluent without prior treatment to the receiving water body. To obtain the environmental license, the effluents generated by the aquaculture activity must comply with the recommendations contained in the legislation. In the State of São Paulo, the State Decree 62.243 of November 1, 2016 the rules and procedures for environmental licensing of São Paulo aquaculture are available, promoting actions to strengthen and encourage São Paulo aquaculture. In view of the need to regularize aquaculture enterprises, economically and environmentally viable technologies may become options for producers to regularize their activity. Artificial Floating Islands (AFIs) are alternative technology for the treatment of fish farming effluents and their efficiency in nutrient retention has been demonstrated. The present study discusses the role of this AFIs in relation to the adequacy of tilapia farming effluent of environmental legislation. For this purpose, six nurseries for fattening Nile tilapia with and without AFIs were used in this research. The results showed that among the variables analyzed, the phosphorous levels did not reach concentrations to adapt the current environmental legislation, that is, lower than 50 Îg L-1. The application of good management practices with better feed conversion and flow control can reduce the overload of this element on the system and thus allow better efficiency of nutrient retention by the AFIs. [ABSTRACT FROM AUTHOR]

As host community diversity decreases, parasite diversity may also decline. The life cycles of trematodes involve multiple hosts from different orders, with many trematodes displaying narrow host specialization. In the 1960s and 2010s, we performed full-body necropsies of juvenile or first-year birds of four wetland bird species, Anas platyrhynchos, Aythya fuligula, Fulica atra, and Chroicocephalus ridibundus which originated from the southern Czech Republic, and examined them for the presence of trematodes. We compared the trematode species richness and diversity of the analyzed component communities. We found complete disintegration of host-parasite networks, which led to declining populations and local extinctions of the majority of trematode species, particularly those with narrow host preferences. For example, in black-headed gulls, 67% of trematode species recorded in the 1960s were absent in gulls that were examined in the 2010s. In contrast, we did not identify any trematode species that were absent in the 1960s but present in the 2010s. This collapse provides new insight into the recent debate regarding whether human-caused extinctions should be considered a problem when locally extinct host species are replaced by an equal or even higher number of nonnative species, thus maintaining local alpha diversities but leading to biotic homogenization and consequently reducing beta diversity. By documenting the collapse of the host-parasite network, we provide a strong argument that biodiversity cannot be assessed by simple measures alone, as only local-scale conservation measures allow the preservation of host-pathogen interactions and nutrient cycles and thus prevent the loss of low-visibility species, such as helminths. [ABSTRACT FROM AUTHOR]

Fishponds are man-made shallow water bodies that are still little studied because of their small size. They represent high value ecosystems, both environmentally (biodiversity hotspot) and economically (fish production). They can have a high place on the hydrographic network, so their influence on water quality is of first importance for rivers and water bodies located downstream and monitored under the Water Framework Directive. These small water bodies can be a source of contaminants during draining period or an efficient buffer for pesticides. We wanted to evaluate whether these ponds could also be a remediation tool against metals by following the annual evolution of upstream/downstream flows. Cadmium, copper, lead and zinc concentrations were quantified in the dissolved phase upstream and downstream of three ponds, each one having a specific agricultural environment (traditional or organic). Metal concentration was quantified in sediments and water. For the dissolved phase, the predictive non-effect concentration was often exceeded, suggesting an environmental risk. Results highlighted also greater quantity of metals at the downstream of the pond compared to the upstream, suggesting remobilization into the ponds or direct cross-sectional contributions from the watershed (e.g. runoff from crops) or even remobilization. Regarding sediments, minimal contamination was shown but a high mineralogical variability. No buffer effect of ponds, which could reduce the risk of acute or chronic toxicity, was detected. [ABSTRACT FROM AUTHOR]

A paleoecological study was performed on a sediment core recovered from a former artificial lake – the Reedbed of Sic near Cluj-Napoca, Romania – in order to explore the history of water management and nearby salt mining, and its impact on the environment. From the Roman period, the area served as a recipient of salty wastewaters. The most significant shift in the sediment composition and macrofossil assemblages took place after 1000 AD, suggesting a significant upturn in salt mining. The impact of mining-related activities was further increased in the Middle Ages when, according to documentary sources, fishponds and watermills were constructed in the area. They led to the stabilisation of the water level in the lakebed, and enhanced the appearance of reed beds and the spread of secondary salt marsh vegetation. This biotop was later invaded by the Entzia macrescens, an agglutinated foraminiferal taxon, known mostly from the high intertidal marshes worldwide. In the investigated marshland, the dominance of halophytic species reached their acme in the seventeenth century, which coincides with the acme of mining activities. This medieval – early Modern Age industrial ecosystem survived the abandonment of salt mines and fishponds, being preserved until today. [ABSTRACT FROM AUTHOR]

Anthropogenic impacts on carp pond environments have increased over the last 100-150 years in Central Europe. Present semi-intensive carp pond management combines natural food resources, supplementary feeding and additional intensification measures such as manuring, liming, and winter and summer drainage. Despite increased eutrophication and fish stock pressure, many carp ponds still serve as habitats for threatened biota, including macrophytes. Both the ecologically essential role of aquatic macrophytes and the impacts that reared fish may have on them have been repeatedly reported in the literature; however, information is scattered and there exists no multidisciplinary synthesis of knowledge of fish farming and plant interactions for European carp ponds. In this review, we show that macrophytes from different ecological groups have specific demands regarding optimal ecological conditions (e.g. pH and trophy level); hence, they can act as indicators of a water body's ecological status. Nevertheless, the overall ecological ranges of many species (i.e. the limits enabling their survival) remain rather broad. Moreover, interactions between the different elements within carp pond ecosystems are complex and change rapidly, facilitating the co-existence of macrophytes with contradictory ecological demands. As the literature suggests, carp ponds may play a role in biodiversity protection that is just as important (or even more so) than that of natural wetlands. Sustainable, environmentally friendly carp pond management is undoubtedly the best means of preserving the unique natural and cultural value of these aquatic ecosystems for the future. [ABSTRACT FROM AUTHOR]

Inland aquaculture in Bangladesh has been growing fast in the last decade. The underlying land use/land cover (LULC) change is an important indicator of socioeconomic and food structure change in Bangladesh, and fishpond mapping is essential to understand such LULC change. Previous research often used water indexes (WI), such as Normalized Difference Water Index (NDWI) and Modified Normalized Difference Water Index (MNDWI), to enhance water bodies and use shape-based metrics to assist classification of individual water features, such as coastal aquaculture ponds. However, inland fishponds in Bangladesh are generally extremely small, and little research has investigated mapping of such small water objects without high-resolution images. Thus, this research aimed to bridge the knowledge gap by developing and evaluating an automatic fishpond mapping workflow with Sentinel-2 images that is implemented on Google Earth Engine (GEE) platform. The workflow mainly includes two steps: (1) the spectral filtering phase that uses a pixel selection technique and an image segmentation method to automatically identify all-year-inundated water bodies and (2) spatial filtering phase to further classify all-year-inundated water bodies into fishponds and non-fishponds using object-based features (OBF). To evaluate the performance of the workflow, we conducted a case study in the Singra Upazila of Bangladesh, and our method can efficiently map inland fishponds with a precision score of 0.788. Our results also show that the pixel selection technique is essential in identifying inland fishponds that are generally small. As the workflow is implemented on GEE, it can be conveniently applied to other regions.

This study reports results of faunistic survey of aquatic beetles and heteropterans in fifteen selected protected areas in South Bohemia. We used baited funnel traps, light traps and strainer for sampling. Altogether, we found 63 species of aquatic beetles from ten families and 18 species of aquatic heteropterans from nine families. During the survey, we found a protected diving beetle Graphoderus bilineatus at one new location (Strhaný fishpond, V Luhu Nature Monument) and small diving beetle Bidessus grossepunctatus at one peat bog (Hliníř Nature Monument). [ABSTRACT FROM AUTHOR]

In the period from 2012 to 2014, twenty localities with a varying density level of the invasive bryozoan Pectinatella magnifica were investigated in the Třeboň region. These localities included water bodies ranging from eutrophic-hypertrophic fishponds to mesotrophic-oligotrophic flooded sandpits. The aim of the study was to investigate and compare the water bodies’ physical, hydrochemical and hydrobiological parameters. Control localities (localities with absence of P. magnifica) were found to be significantly different from localities with occurrence of P. magnifica in most of the measured parameters. Also shown was that P. magnifica tends to form colonies in localities showing above-average qualitative parameters within the Třeboň region: balanced oxygen and pH regime, low concentration of suspended solids (Secchi depth over 1 m) and nitrogen forms (mean TN 1.5 mg L−1), chlorophyll-a mean concentration 54 µg L−1, and zooplankton mean density 117 ind L−1 and biomass 2 mg of wet weight L−1. Furthermore, P. magnifica was also found in brown humic waters. While the sites with P. magnifica occurrence are often mesotrophic flooded sandpits and fishponds under nature protection, fishponds for recreational use, and those with low intensity of fishery management (without formation of massive cyanobacterial water blooms, oxygen regime fluctuations, etc.), localities unoccupied by invasive bryozoans are mostly strictly eutrophic-hypertrophic, semi-intensified, carp fishponds. [ABSTRACT FROM AUTHOR]

Invasive parasites represent a serious problem due to their capacity to threaten local populations of native (often endemic) hosts, and fishes in breeding facilities. Tapeworms (Cestoda) are extremely adapted (they lack any gut and circulatory system) parasitic flatworms some of which have colonised new geographical regions as a result of unintentional transfer of hosts infected with these parasites. The highest number of invasive parasites within this host-parasite system is among tapeworms parasitizing common carp (Cyprinus carpio L.), which has also been introduced globally. In the present study, we report another record of the Asian non-native fish tapeworm Khawia japonensis (Yamaguti, 1934) (Cestoda: Caryophyllidea) from common carp in Europe. Previous records of this cestode from Italy (Po River basin) and Slovakia (Danube River basin) and its present finding in the Czech Republic (Elbe River basin) confirms recent expansion of the parasite in Europe. Potential impacts of this non-native parasite on common carp in commercial breeding fisheries should be carefully studied. [ABSTRACT FROM AUTHOR]

The medieval market-town of Sic (Szék in Hungarian) was an important Transylvanian settlement due to its remarkable salt mining. The impact of the mining activities on the environment and the history of water management were investigated based on a palaeoecological study, performed on the large Reedbed of Sic (Stufărişurile/Nádas-tó). We found that in the last 3000 years the anthropogenic impact has been continuous in the territory, but the types and intensity of the disturbances changed with time. The most notable environmental transitions took place after 1000 AD, suggesting a significant intensification of salt mining. Forest cover significantly drop, but salt concentration and the frequency of halophytic species in the investigated marshland increased during the Late Middle Ages. The dominance of halophytic marshland species reached their peak in the 17th century. This coincides with the apogee of mining activities and human lake management. The most remarkable deforestation occurred in the 18th century, when the present-day landscape with negligible forest cover was developed. [ABSTRACT FROM AUTHOR]

The Clapar landslide induced debris flow consisted of the Clapar landslide occurred on 24 March 2017 and the Clapar debris flow occurred on 29 March 2017. The first investigation of the Clapar landslide induced debris flow was carried out two months after the disaster. It was followed by UAV mapping, extensive interviews, newspaper compilation, visual observation and field measurements, and video analysis in order to understand chronology and triggering mechanism of the landslide induced debris flow in Clapar. The 24 March 2016 landslide occurred after 5 hours of consecutive rainfall (11,2 mm) and was affected by combination of fishponds leak and infiltration of antecedent rain. After five days of the Clapar landslide, landslide partially mobilized to form debris flow where the head scarp of debris flow was located at the foot of the 24 March 2016 landslide. The Clapar debris flow occurred when there was no rainfall. It was not generated by rainstorm or the surface erosion of the river bed, but rather by water infiltration through the crack formed on the toe of the 24 March 2016 landslide. Supply of water to the marine clay deposit might have increased pore water pressure and mobilized the soil layer above. The amount of water accumulated in the temporary pond at the main body of the 24 March 2016 landslide might have also triggered the Clapar debris flow. The area of Clapar landslide still shows the possibility of further retrogression of the landslide body which may induce another debris flow. Understanding precursory factors triggering landslides and debris flows in Banjarnegara based on data from monitoring systems and laboratory experiments is essential to minimize the risk of future landslide. [ABSTRACT FROM AUTHOR]

En 2013 l’auteur a présenté une première liste de 10 viviers d’Afrique (bassins avec amphores dans les parois) : 2 d’époque punique à Carthage, 8 d’époque romaine : 3 en Proconsulaire (Carthage, Bulla Regia et Thuburbo Maius), 4 en Numidie (Cuicul et Thamugadi) , et 1 en Egypte (Karnak). On peut maintenant ajouter un exemple en Numidie, près de Boumia (Batna). L’auteur invite les savants à enrichir cette enquête