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Roy K, Kajgrova L, Capkova L, Zabransky L, Petraskova E, Dvorak P, Nahlik V, Kuebutornye FKA, Blabolil P, Blaha M, Vrba J, Mraz J. Synergistic digestibility effect by planktonic natural food and habitat renders high digestion efficiency in agastric aquatic consumers. Sci Total Environ 2024; 927:172105. [PMID: 38556011 DOI: 10.1016/j.scitotenv.2024.172105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2024] [Revised: 03/17/2024] [Accepted: 03/28/2024] [Indexed: 04/02/2024]
Abstract
A digestibility enhancing effect of natural food on stomachless fish model (Cyprinus carpio) was verified by fluorogenic substrate assays of enzymatic activities in experimental pond carp gut flush and planktonic food over a full vegetative season. Then compared with size-matched conspecific grown artificially (tank carp) and an advanced omnivore species possessing true stomach (tilapia, Oreochromis niloticus). Results suggested activities of digestive enzymes (except amylolytic) were significantly higher in pond carp (p ≤ 0.05) than in the size-matched tank carp. Even compared to tilapia, pond carp appeared superior (p < 0.05; proteolytic or chitinolytic activities) or comparable (p > 0.05; phosphatase or cellulolytic activities). Amylolytic, chitinolytic, and phosphatases activities in pond carp gut significantly increased (p ≤ 0.01) over season. Several orders-of-magnitude higher enzymatic activities were detected in planktonic natural food than expressed in carp gut. Amino acid markers in planktonic food revealed a higher share of zooplankton (microcrustaceans), but not phytoplankton, synchronized with higher activities of complex polysaccharide-splitting enzymes (cellulolytic and chitinolytic) in fish gut. Periods of clear water phase low in chlorophyll-a and nutrients, but high in certain zooplankton (preferably cladocerans), may create a synergistic digestibility effect in pond carp. We conclude aquatic ecosystem components (natural food, water, microbiota) enhance fishes' hydrolyzing capabilities of C/N/P macromolecules and even their complex polymers such as cellulose, chitin, and maybe phytate (to be validated), to the extent that being stomachless is not an issue. Aquatic nutritional ecologists may consider that laboratory-based understandings of digestibility may underestimate digestion efficiency of free-ranging fish in ponds or lakes.
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Affiliation(s)
- Koushik Roy
- University of South Bohemia in České Budějovice, Faculty of Fisheries and Protection of Waters, South Bohemian Research Centre of Aquaculture and Biodiversity of Hydrocenoses, 370 05 České Budějovice, Czech Republic.
| | - Lenka Kajgrova
- University of South Bohemia in České Budějovice, Faculty of Fisheries and Protection of Waters, South Bohemian Research Centre of Aquaculture and Biodiversity of Hydrocenoses, 370 05 České Budějovice, Czech Republic
| | - Lenka Capkova
- University of South Bohemia in České Budějovice, Faculty of Science, 370 05 České Budějovice, Czech Republic
| | - Lubos Zabransky
- University of South Bohemia in České Budějovice, Faculty of Agriculture and Technology, 370 05 České Budějovice, Czech Republic
| | - Eva Petraskova
- University of South Bohemia in České Budějovice, Faculty of Agriculture and Technology, 370 05 České Budějovice, Czech Republic
| | - Petr Dvorak
- University of South Bohemia in České Budějovice, Faculty of Fisheries and Protection of Waters, South Bohemian Research Centre of Aquaculture and Biodiversity of Hydrocenoses, 370 05 České Budějovice, Czech Republic
| | - Vit Nahlik
- University of South Bohemia in České Budějovice, Faculty of Fisheries and Protection of Waters, South Bohemian Research Centre of Aquaculture and Biodiversity of Hydrocenoses, 370 05 České Budějovice, Czech Republic
| | - Felix Kofi Agbeko Kuebutornye
- University of South Bohemia in České Budějovice, Faculty of Fisheries and Protection of Waters, South Bohemian Research Centre of Aquaculture and Biodiversity of Hydrocenoses, 370 05 České Budějovice, Czech Republic
| | - Petr Blabolil
- University of South Bohemia in České Budějovice, Faculty of Science, 370 05 České Budějovice, Czech Republic
| | - Martin Blaha
- University of South Bohemia in České Budějovice, Faculty of Fisheries and Protection of Waters, South Bohemian Research Centre of Aquaculture and Biodiversity of Hydrocenoses, 370 05 České Budějovice, Czech Republic
| | - Jaroslav Vrba
- University of South Bohemia in České Budějovice, Faculty of Science, 370 05 České Budějovice, Czech Republic
| | - Jan Mraz
- University of South Bohemia in České Budějovice, Faculty of Fisheries and Protection of Waters, South Bohemian Research Centre of Aquaculture and Biodiversity of Hydrocenoses, 370 05 České Budějovice, Czech Republic
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Jůza T, Muška M, Blabolil P, Kočvara L, Sajdlová Z, Dumpis J, Medne R. Spatial fish distribution in autumn in a shallow mesotrophic lake, assessed by hydroacoustic surveys, trawling, and beach seining. J Fish Biol 2024. [PMID: 38403049 DOI: 10.1111/jfb.15691] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Received: 11/09/2023] [Revised: 01/30/2024] [Accepted: 02/04/2024] [Indexed: 02/27/2024]
Abstract
Day and nighttime autumn fish abundance and biomass were studied in the pelagic and littoral zones of Lake Sauka in Latvia. Both pelagic methods (hydroacoustics and trawling) revealed significantly higher fish abundance and biomass during the day than at night, especially in deeper zones (below 3 m). Roach (Rutilus rutilus) and Eurasian perch (Perca fluviatilis) dominated the trawl catches during the day, while roach and ruffe dominated at night. Fish smaller than 14 cm strongly dominated in both the trawl catches and hydroacoustic observations. Our hydroacoustic sampling found inhomogeneous pelagic distributions of fish aggregated in big shoals during the day. In the littoral zone, which was sampled by beach seining, both the abundance and biomass were significantly higher at night than during the day. Roach, bleak, and European perch usually dominated in beach seine catches during the day and at night. The daytime pelagic biomass found by hydroacoustics was 62 kg/ha and it decreased to approximately 11 kg/ha at night. The littoral biomass found by beach seining was diurnally opposite, 4 kg/ha during the day and 37 kg/ha at night. It is obvious that diurnal horizontal migrations between pelagic and littoral zones, and shoaling behavior during the daytime are common patterns in the shallow Lake Sauka during the autumn. The study of the spatial distribution of fish is extremely important for the establishment of an appropriate monitoring plan for the purposes of the Water Framework Directive with regard to the morphometry of the lake, the geographical location, and the sampling period of the year. This study also shows that the combination of completely non-invasive hydroacoustic and other methods that are invasive (trawls, beach seines) but not as destructive as gillnets, which are normally used for scientific fish monitoring in Europe, could be a future way forward for fish monitoring.
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Affiliation(s)
- Tomáš Jůza
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, České Budějovice, Czech Republic
| | - Milan Muška
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, České Budějovice, Czech Republic
| | - Petr Blabolil
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, České Budějovice, Czech Republic
- University of South Bohemia in České Budějovice, Faculty of Science, České Budějovice, Czech Republic
| | - Luboš Kočvara
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, České Budějovice, Czech Republic
| | - Zuzana Sajdlová
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, České Budějovice, Czech Republic
| | - Janis Dumpis
- Institute for Food Safety, Animal Health and Environment BIOR, Riga, Latvia
- Latvia University of Life Sciences and Technologies, Jelgava, Latvia
| | - Ruta Medne
- Institute for Food Safety, Animal Health and Environment BIOR, Riga, Latvia
- Latvia University of Life Sciences and Technologies, Jelgava, Latvia
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Vejřík L, Vejříková I, Sajdlová Z, Kočvara L, Kolařík T, Bartoň D, Jůza T, Blabolil P, Peterka J, Čech M, Vašek M. A non-lethal stable isotope analysis of valued freshwater predatory fish using blood and fin tissues as alternatives to muscle tissue. PLoS One 2024; 19:e0297070. [PMID: 38236915 PMCID: PMC10796030 DOI: 10.1371/journal.pone.0297070] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Accepted: 12/23/2023] [Indexed: 01/22/2024] Open
Abstract
Stable isotope analysis (SIA) is widely used to study trophic ecology and food webs in aquatic ecosystems. In the case of fish, muscle tissue is generally preferred for SIA, and the method is lethal in most cases. We tested whether blood and fin clips can be used as non-lethal alternatives to muscle tissue for examining the isotopic composition of two freshwater predatory fish, European catfish (Silurus glanis) and Northern pike (Esox lucius), species of high value for many freshwater systems as well as invasive species in many others. Blood samples from the caudal vein, anal fin clips, and dorsal muscle obtained by biopsy punch were collected from four catfish and pike populations (14-18 individuals per population). Subsequently, these samples were analyzed for δ13C and δ15N. The effects of alternative tissues, study site, and fish body mass on the isotopic offset were investigated. Both species showed a correlation between the isotopic offset and the tissue type, as well as the study site, but no significant relationship with the body mass. The isotopic offsets between tissues were used to calculate the conversion equations. The results demonstrated that both blood and fin clips are suitable and less invasive alternative to muscle in SIA studies focused on European catfish and Northern pike. Blood provided better correspondence to muscle isotope values. However, our results clearly demonstrated that isotopic offsets between tissues vary significantly among populations of the same species. Therefore, obtaining a muscle biopsy from several individuals in any population is advisable to gain initial insights and establish a possible population-specific inter-tissue conversion.
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Affiliation(s)
- Lukáš Vejřík
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, České Budějovice, Czech Republic
| | - Ivana Vejříková
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, České Budějovice, Czech Republic
| | - Zuzana Sajdlová
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, České Budějovice, Czech Republic
| | - Luboš Kočvara
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, České Budějovice, Czech Republic
| | - Tomáš Kolařík
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, České Budějovice, Czech Republic
| | - Daniel Bartoň
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, České Budějovice, Czech Republic
| | - Tomáš Jůza
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, České Budějovice, Czech Republic
| | - Petr Blabolil
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, České Budějovice, Czech Republic
- Faculty of Science, University of South Bohemia in České Budějovice, České Budějovice, Czech Republic
| | - Jiří Peterka
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, České Budějovice, Czech Republic
| | - Martin Čech
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, České Budějovice, Czech Republic
| | - Mojmír Vašek
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, České Budějovice, Czech Republic
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Vejřík L, Vejříková I, Blabolil P, Sajdlová Z, Kočvara L, Kolařík T, Bartoň D, Jůza T, Šmejkal M, Peterka J, Čech M. Trophic Position of the Species and Site Trophic State Affect Diet Niche and Individual Specialization: From Apex Predator to Herbivore. Biology (Basel) 2023; 12:1113. [PMID: 37626997 PMCID: PMC10452534 DOI: 10.3390/biology12081113] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2023] [Revised: 07/31/2023] [Accepted: 08/04/2023] [Indexed: 08/27/2023]
Abstract
Intra-species variability in isotopic niches, specifically isotopic total niche width (ITNW), isotopic individual niche width (IINW), and isotopic individual specialization (IIS), was studied using an innovative approach without sacrificing the vertebrates. Stable isotopes (δ13C, δ15N) in four body tissues differing in isotopic half-life were analyzed from four freshwater fish species representing different trophic positions. ITNW was widest for the apex predator (European catfish) and narrowest for the obligate predator (Northern pike). IINW exhibited a polynomial trend for the European catfish, Northern pike, and Eurasian perch (mesopredator), decreasing with body mass and increasing again after exceeding a certain species-dependent body mass threshold. Thus, for ectotherms, apex predator status is linked rather to its size than to the species. In herbivores (rudd), IINW increased with body mass. The IIS of predators negatively correlated with site trophic state. Therefore, eutrophication can significantly change the foraging behavior of certain species. We assume that the observed trends will occur in other species at similar trophic positions in either aquatic or terrestrial systems. For confirmation, we recommend conducting a similar study on other species in different habitats.
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Affiliation(s)
- Lukáš Vejřík
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, Na Sádkách 7, 37005 České Budějovice, Czech Republic; (L.V.); (P.B.); (Z.S.); (L.K.); (T.K.); (D.B.); (T.J.); (M.Š.); (J.P.); (M.Č.)
| | - Ivana Vejříková
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, Na Sádkách 7, 37005 České Budějovice, Czech Republic; (L.V.); (P.B.); (Z.S.); (L.K.); (T.K.); (D.B.); (T.J.); (M.Š.); (J.P.); (M.Č.)
| | - Petr Blabolil
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, Na Sádkách 7, 37005 České Budějovice, Czech Republic; (L.V.); (P.B.); (Z.S.); (L.K.); (T.K.); (D.B.); (T.J.); (M.Š.); (J.P.); (M.Č.)
- Faculty of Science, University of South Bohemia in České Budějovice, Branišovská 31, 37005 České Budějovice, Czech Republic
| | - Zuzana Sajdlová
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, Na Sádkách 7, 37005 České Budějovice, Czech Republic; (L.V.); (P.B.); (Z.S.); (L.K.); (T.K.); (D.B.); (T.J.); (M.Š.); (J.P.); (M.Č.)
| | - Luboš Kočvara
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, Na Sádkách 7, 37005 České Budějovice, Czech Republic; (L.V.); (P.B.); (Z.S.); (L.K.); (T.K.); (D.B.); (T.J.); (M.Š.); (J.P.); (M.Č.)
| | - Tomáš Kolařík
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, Na Sádkách 7, 37005 České Budějovice, Czech Republic; (L.V.); (P.B.); (Z.S.); (L.K.); (T.K.); (D.B.); (T.J.); (M.Š.); (J.P.); (M.Č.)
| | - Daniel Bartoň
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, Na Sádkách 7, 37005 České Budějovice, Czech Republic; (L.V.); (P.B.); (Z.S.); (L.K.); (T.K.); (D.B.); (T.J.); (M.Š.); (J.P.); (M.Č.)
| | - Tomáš Jůza
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, Na Sádkách 7, 37005 České Budějovice, Czech Republic; (L.V.); (P.B.); (Z.S.); (L.K.); (T.K.); (D.B.); (T.J.); (M.Š.); (J.P.); (M.Č.)
| | - Marek Šmejkal
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, Na Sádkách 7, 37005 České Budějovice, Czech Republic; (L.V.); (P.B.); (Z.S.); (L.K.); (T.K.); (D.B.); (T.J.); (M.Š.); (J.P.); (M.Č.)
| | - Jiří Peterka
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, Na Sádkách 7, 37005 České Budějovice, Czech Republic; (L.V.); (P.B.); (Z.S.); (L.K.); (T.K.); (D.B.); (T.J.); (M.Š.); (J.P.); (M.Č.)
| | - Martin Čech
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, Na Sádkách 7, 37005 České Budějovice, Czech Republic; (L.V.); (P.B.); (Z.S.); (L.K.); (T.K.); (D.B.); (T.J.); (M.Š.); (J.P.); (M.Č.)
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Kajgrová L, Drozd B, Regenda J, Draštík V, Kočvara L, Kolařík T, Peterka J, Blabolil P. A comparative study of three fishery methods for sampling the invasive topmouth gudgeon (Pseudorasbora parva) in ponds. J Fish Biol 2023; 102:1121-1128. [PMID: 36855935 DOI: 10.1111/jfb.15361] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Accepted: 02/22/2023] [Indexed: 05/13/2023]
Abstract
Invasive fish threaten ponds' ecological status and their ecosystem services, therefore obtaining a representative sample of fish community composition is fundamental to fishery management, research and nature conservation. Estimates of the size distribution, density and biomass of the topmouth gudgeon (Pseudorasbora parva) model species of invasive fish in three ponds were compared among three sampling methods: electrofishing, fish-trapping and throw-netting. The study illustrates that the invasive fish, P. parva, can be detected by all tested fishing methods, yet our results clearly showed that there are pronounced differences among methods in population characteristic estimates. Electrofishing and throw-netting gave biased information on the size distribution of P. parva. Fish-trapping and throw-netting gave reasonable P. parva density and biomass estimates, while electrofishing clearly underestimated it. All tested methods showed a body size increment of P. parva between summer and autumn sampling sessions, yet neither throw-netting nor electrofishing recorded an increment in its density. Our study showed that fish-trapping is the most reliable and affordable method to estimate invasive P. parva population characteristics in ponds despite more time-demanding sampling. The success depends on the mesh size of sampling gear, operator skill and habitat structure. The cost-effectiveness of the selected methods and the importance of invasive fish monitoring in ponds is discussed. The sampling gear must be considered carefully according to the aim of the monitoring.
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Affiliation(s)
- Lenka Kajgrová
- Faculty of Fisheries and Protection of Waters, South Bohemian Research Center of Aquaculture and Biodiversity of Hydrocenoses, Institute of Aquaculture and Protection of Waters, University of South Bohemia in České Budějovice, České Budějovice, Czech Republic
| | - Bořek Drozd
- Faculty of Fisheries and Protection of Waters, South Bohemian Research Center of Aquaculture and Biodiversity of Hydrocenoses, Institute of Aquaculture and Protection of Waters, University of South Bohemia in České Budějovice, České Budějovice, Czech Republic
| | - Ján Regenda
- Faculty of Fisheries and Protection of Waters, South Bohemian Research Center of Aquaculture and Biodiversity of Hydrocenoses, Institute of Aquaculture and Protection of Waters, University of South Bohemia in České Budějovice, České Budějovice, Czech Republic
| | - Vladislav Draštík
- Institute of Hydrobiology, Biology Centre CAS, České Budějovice, Czech Republic
| | - Luboš Kočvara
- Institute of Hydrobiology, Biology Centre CAS, České Budějovice, Czech Republic
| | - Tomáš Kolařík
- Institute of Hydrobiology, Biology Centre CAS, České Budějovice, Czech Republic
| | - Jiří Peterka
- Institute of Hydrobiology, Biology Centre CAS, České Budějovice, Czech Republic
| | - Petr Blabolil
- Institute of Hydrobiology, Biology Centre CAS, České Budějovice, Czech Republic
- Faculty of Science, University of South Bohemia in České Budějovice, České Budějovice, Czech Republic
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Šmejkal M, Bartoň D, Blabolil P, Kolařík T, Kubečka J, Sajdlová Z, Souza AT, Brabec M. Diverse environmental cues drive the size of reproductive aggregation in a rheophilic fish. Mov Ecol 2023; 11:16. [PMID: 36949527 PMCID: PMC10035167 DOI: 10.1186/s40462-023-00379-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/04/2022] [Accepted: 03/09/2023] [Indexed: 06/18/2023]
Abstract
BACKGROUND Animal migrations are periodic and relatively predictable events, and their precise timing is essential to the reproductive success. Despite large scientific effort in monitoring animal reproductive phenology, identification of complex environmental cues that determine the timing of reproductive migrations and temporal changes in the size of reproductive aggregations in relation to environmental variables is relatively rare in the current scientific literature. METHODS We tagged and tracked 1702 individuals of asp (Leuciscus aspius), a large minnow species, and monitored with a resolution of one hour the size of their reproductive aggregations (counts of sexes present at the breeding grounds standardized by the sum of individuals in the season) over seven breeding seasons using passive integrated transponder tag systems. We examined the size of reproductive aggregations in relation to environmental cues of day number within a reproductive season (intra-year seasonality), water temperature, discharge, hour in a day (intra-day pattern), temperature difference between water and air, precipitation, atmospheric pressure, wind speed and lunar phase. A generalized additive model integrating evidence from seven breeding seasons and providing typical dynamics of reproductive aggregations was constructed. RESULTS We demonstrated that all environmental cues considered contributed to the changes in the size of reproductive aggregations during breeding season, and that some effects varied during breeding season. Our model explained approximately 50% of the variability in the data and the effects were sex-dependent (models of the same structure were fitted to each sex separately, so that we effectively stratified on sex). The size of reproductive aggregations increased unimodally in response to day in season, correlated positively with water temperature and wind speed, was highest before and after the full moon, and highest at night (interacting with day in a season). Males responded negatively and females positively to increase in atmospheric pressure. CONCLUSION The data demonstrate complex utilization of available environmental cues to time reproductive aggregations in freshwater fish and their interactions during the reproductive season. The study highlights the need to acquire diverse data sets consisting of many environmental cues to achieve high accuracy of interpretation of reproductive timing.
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Affiliation(s)
- Marek Šmejkal
- Institute of Hydrobiology, Biology Centre of the Czech Academy of Sciences, České Budějovice, Czech Republic.
| | - Daniel Bartoň
- Institute of Hydrobiology, Biology Centre of the Czech Academy of Sciences, České Budějovice, Czech Republic
| | - Petr Blabolil
- Institute of Hydrobiology, Biology Centre of the Czech Academy of Sciences, České Budějovice, Czech Republic
| | - Tomáš Kolařík
- Institute of Hydrobiology, Biology Centre of the Czech Academy of Sciences, České Budějovice, Czech Republic
| | - Jan Kubečka
- Institute of Hydrobiology, Biology Centre of the Czech Academy of Sciences, České Budějovice, Czech Republic
| | - Zuzana Sajdlová
- Institute of Hydrobiology, Biology Centre of the Czech Academy of Sciences, České Budějovice, Czech Republic
| | - Allan T Souza
- Institute of Hydrobiology, Biology Centre of the Czech Academy of Sciences, České Budějovice, Czech Republic
- Institute for Atmospheric and Earth System Research INAR, Forest Sciences, Faculty of Agriculture and Forestry, University of Helsinki, Helsinki, Finland
| | - Marek Brabec
- Institute of Computer Science, Czech Academy of Sciences, Prague, Czech Republic
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Vašek M, Brabec M, Blabolil P, Čech M, Draštík V, Jůza T, Kubečka J, Muška M, Peterka J, Prchalová M, Říha M, Hejzlar J. Fish scale stable isotopes as potential indicators of nutrient pollution: Exploring the response of roach (Rutilus rutilus) scale δ 15N and δ 13C to a gradient of land use disturbance. Sci Total Environ 2023; 865:161198. [PMID: 36592901 DOI: 10.1016/j.scitotenv.2022.161198] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Revised: 12/21/2022] [Accepted: 12/22/2022] [Indexed: 06/17/2023]
Abstract
To examine the suitability of fish scales as potential tracers of nutrient pollution, we analysed the nitrogen and carbon stable isotope values (δ15N and δ13C) in scales of a generalist fish species, roach Rutilus rutilus, collected from 22 Czech reservoirs covering wide gradients of catchment land use and nutrient enrichment. Using generalised additive mixed models in the first step and generalised linear mixed models in the second step, we evaluated the response of roach scale stable isotope values to catchment land use variables (percentage of agricultural land and human population density) and in-reservoir water quality variables. Roach scale δ15N values varied by 15 ‰ among the reservoirs and were strongly, linearly, and positively associated with the percentage of agricultural land in the reservoir catchments, pointing to agriculture as the dominant source of nitrogen pollution in the investigated systems. Roach scale δ13C values differed by 8 ‰ among the studied reservoirs and were not related to catchment land use variables or in-reservoir primary production (chlorophyll-a levels). Possible variation in roach foraging strategies (littoral versus pelagic) between reservoirs or the contrasting effects of eutrophication-related autotrophic and heterotrophic processes on baseline δ13C values may explain the lack of relationships between roach scale δ13C values and the explanatory variables. In summary, our findings show that fish scale δ15N values are sensitive bioindicators of catchment-derived anthropogenic nitrogen inputs to freshwater ecosystems. Because scales can be sampled in a nonlethal way and δ15N analysis is relatively inexpensive, we suggest that measuring the δ15N values of fish scales could be an effective method for monitoring nitrogen pollution in aquatic environments.
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Affiliation(s)
- Mojmír Vašek
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, Na Sádkách 7, České Budějovice 37005, Czech Republic.
| | - Marek Brabec
- Institute of Computer Science of the Czech Academy of Sciences, Pod Vodárenskou věží 2, Praha 18207, Czech Republic.
| | - Petr Blabolil
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, Na Sádkách 7, České Budějovice 37005, Czech Republic; University of South Bohemia, Faculty of Science, Branišovská 1760, České Budějovice 37005, Czech Republic.
| | - Martin Čech
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, Na Sádkách 7, České Budějovice 37005, Czech Republic.
| | - Vladislav Draštík
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, Na Sádkách 7, České Budějovice 37005, Czech Republic.
| | - Tomáš Jůza
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, Na Sádkách 7, České Budějovice 37005, Czech Republic.
| | - Jan Kubečka
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, Na Sádkách 7, České Budějovice 37005, Czech Republic.
| | - Milan Muška
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, Na Sádkách 7, České Budějovice 37005, Czech Republic.
| | - Jiří Peterka
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, Na Sádkách 7, České Budějovice 37005, Czech Republic.
| | - Marie Prchalová
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, Na Sádkách 7, České Budějovice 37005, Czech Republic.
| | - Milan Říha
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, Na Sádkách 7, České Budějovice 37005, Czech Republic.
| | - Josef Hejzlar
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, Na Sádkách 7, České Budějovice 37005, Czech Republic.
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8
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Nazarizadeh M, Peterka J, Kubečka J, Vašek M, Jůza T, de Moraes KR, Čech M, Holubová M, Souza AT, Blabolil P, Muška M, Tsering L, Bartoň D, Říha M, Šmejkal M, Tušer M, Vejřík L, Frouzová J, Jarić I, Prchalová M, Vejříková I, Štefka J. Different hosts in different lakes: prevalence and population genetic structure of plerocercoids of Ligula intestinalis (Cestoda) in Czech water bodies. Folia Parasitol (Praha) 2022; 69. [DOI: 10.14411/fp.2022.018] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Accepted: 04/26/2022] [Indexed: 01/05/2023]
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9
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Golpour A, Šmejkal M, Čech M, dos Santos RA, Souza AT, Jůza T, Martínez C, Bartoň D, Vašek M, Draštík V, Kolařík T, Kočvara L, Říha M, Peterka J, Blabolil P. Similarities and Differences in Fish Community Composition Accessed by Electrofishing, Gill Netting, Seining, Trawling, and Water eDNA Metabarcoding in Temperate Reservoirs. Front Ecol Evol 2022. [DOI: 10.3389/fevo.2022.913279] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
It is difficult to understand the composition and diversity of biological communities in complex and heterogeneous environments using traditional sampling methods. Recently, developments in environmental DNA metabarcoding have emerged as a powerful, non-invasive method for comprehensive community characterization and biodiversity monitoring in different types of aquatic ecosystems. In this study, water eDNA targeting fish (wf-eDNA) and four traditional fish sampling methods (electrofishing, gill netting, seining, trawling) were compared to evaluate the reliability and efficiency of wf-eDNA (vertebrate mitochondrial 12S ribosomal RNA (rRNA) as an alternative approach to assess the diversity and composition of freshwater fish communities. The results of wf-eDNA showed a consistency between the traditional sampling methods regarding species detection. However, some fish species detected using wf-eDNA assay were not detected using traditional sampling methods and vice versa. Comparison of wf-eDNA and traditional sampling methods revealed spatial homogeneity in fish community composition in all reservoirs. Ordination analysis showed that the wf-eDNA approach covers all traditional sampling methods and occupies an intermediate position. In addition, based on the Shannon diversity index, we found that in one reservoir the wf-eDNA method yielded similar fish community diversity to traditional sampling methods. However, in other reservoirs, the calculated Shannon diversity index of the wf-eDNA method was significantly higher than traditional sampling methods. In general, significant positive correlations were found between the wf-eDNA method and almost all traditional sampling methods. We conclude that wf-eDNA seems to be a reliable and complementary approach for biomonitoring and ecosystem management of freshwater ichthyofauna.
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10
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Bartoň D, Brabec M, Sajdlová Z, Souza AT, Duras J, Kortan D, Blabolil P, Vejřík L, Kubečka J, Šmejkal M. Hydropeaking causes spatial shifts in a reproducing rheophilic fish. Sci Total Environ 2022; 806:150649. [PMID: 34597557 DOI: 10.1016/j.scitotenv.2021.150649] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/04/2021] [Revised: 09/20/2021] [Accepted: 09/24/2021] [Indexed: 06/13/2023]
Abstract
The hydropeaking regime below hydropower facilities represents a serious threat to riverine fauna and may cause declines in populations living under its influence. However, the knowledge on direct fish responses to the threat of hydropeaking is limited. Here, we aimed to test whether the hydropeaking generated 12 km upstream may have a negative effect on the position of actively spawning rheophilic fish, asp, Leuciscus aspius. Two passive telemetry antenna arrays were used to record fish position on the spawning ground. We monitored the position of spawning fish (545, 764 and 852 individuals) in three one-month long spawning seasons in 2017-2019 and related the changes in detection probability on the two antenna arrays to flow conditions, temperature, time of a day and individual fish ID. The fish detection on the spawning ground was negatively affected by the flow change (both increase and decrease) in time. Moreover, the probability of fish detection was also influenced by water temperature, the time of the day and, as seen from the magnitude of individual random effect variability, the detection probability was rather individual-specific. Hydropeaking resulted in the change of spawning behaviour and likely caused interruption of spawning or shifting spawning outside the optimal area for egg development. We therefore advise to reduce the hydropeaking regime during the rheophilic fish spawning season under fisheries or conservation interests.
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Affiliation(s)
- Daniel Bartoň
- Institute of Hydrobiology, Biology Centre of the Czech Academy of Sciences, České Budějovice, Czech Republic; Faculty of Science, University of South Bohemia, České Budějovice, Czech Republic
| | - Marek Brabec
- Institute of Computer Science, Czech Academy of Sciences, Prague, Czech Republic
| | - Zuzana Sajdlová
- Institute of Hydrobiology, Biology Centre of the Czech Academy of Sciences, České Budějovice, Czech Republic
| | - Allan T Souza
- Institute of Hydrobiology, Biology Centre of the Czech Academy of Sciences, České Budějovice, Czech Republic
| | - Jindřich Duras
- University of South Bohemia in České Budějovice, Faculty of Fisheries and Protection of Waters, South Bohemian Research Center of Aquaculture and Biodiversity of Hydrocenoses, Vodňany, Czech Republic; Department of Water Management Planning, Vltava River Authority, State Enterprise, Plzeň, Czech Republic
| | - David Kortan
- Department of Biology, State Enterprise Vltava River Authority, České Budějovice, Czech Republic
| | - Petr Blabolil
- Institute of Hydrobiology, Biology Centre of the Czech Academy of Sciences, České Budějovice, Czech Republic
| | - Lukáš Vejřík
- Institute of Hydrobiology, Biology Centre of the Czech Academy of Sciences, České Budějovice, Czech Republic
| | - Jan Kubečka
- Institute of Hydrobiology, Biology Centre of the Czech Academy of Sciences, České Budějovice, Czech Republic
| | - Marek Šmejkal
- Institute of Hydrobiology, Biology Centre of the Czech Academy of Sciences, České Budějovice, Czech Republic.
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11
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Souza AT, Argillier C, Blabolil P, Děd V, Jarić I, Monteoliva AP, Reynaud N, Ribeiro F, Ritterbusch D, Sala P, Šmejkal M, Volta P, Kubečka J. Empirical evidence on the effects of climate on the viability of common carp (Cyprinus carpio) populations in European lakes. Biol Invasions 2022. [DOI: 10.1007/s10530-021-02710-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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12
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Ritterbusch D, Blabolil P, Breine J, Erős T, Mehner T, Olin M, Peirson G, Volta P, Poikane S. European fish-based assessment reveals high diversity of systems for determining ecological status of lakes. Sci Total Environ 2022; 802:149620. [PMID: 34461474 DOI: 10.1016/j.scitotenv.2021.149620] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 08/05/2021] [Accepted: 08/09/2021] [Indexed: 06/13/2023]
Abstract
Triggered by the adoption of the Water Framework Directive, a variety of fish-based systems were developed throughout Europe to assess the ecological status of lakes. This paper provides a comprehensive overview of all existing systems and summarizes sampling methods, fish community traits (metrics) and the relevant anthropogenic pressures assessed by them. Twenty-one European countries developed fish-based assessment systems. Three countries each developed two distinct systems to approach different ecoregions, either to use different data, or to assess different lake types leading to a total number of 24 systems. The most common approach for the setting of reference conditions, used in seventeen systems, was the utilisation of fish communities in comparably undisturbed natural lakes as reference. Eleven used expert judgment, nine historical data and eight modelled relationships. Fourteen systems combined at least two approaches. The most common fish sampling method was a standardized fishing procedure with multimesh-gillnets. Many countries applied combinations of fishing methods, e.g. non-standard gillnets, fyke nets and electrofishing. Altogether 177 metrics were used for index development and each system combined 2-13 metrics. The most common ones were total standardized catches of number and biomass, relative abundance of Perca fluviatilis, Rutilus rutilus, and Abramis brama, feeding preferences, sensitive species, and non-natives. The pressure-response-relationships for these metrics were supported with both correlations established during system development and scientific publications. However, the metrics and their combinations were highly diverse and no metric was applied universally. Our analysis reveals that most fish-based assessment systems address multiple pressures (eutrophication, hydromorphological alterations, fishery pressure and occurrence of non-natives), whilst few are pressure-specific, tackling only eutrophication or acidification. We argue that the value of fish-based systems for lakes lies in their capacity to capture the effect of many different pressures and their interactions which is lacking for most assessment systems based on other biota.
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Affiliation(s)
- David Ritterbusch
- Institute for Inland Fisheries, Im Königswald 2, D-14469 Potsdam, Germany.
| | - Petr Blabolil
- Biology Centre of the Czech Academy of Sciences, Na Sádkách 7, 37005 České Budějovice, Czech Republic.
| | - Jan Breine
- Research Institute for Nature and Forest (INBO), Dwersbos 28, B-1630 Linkebeek, Belgium.
| | - Tibor Erős
- Balaton Limnological Research Institute, Klebelsberg K. u. 3, H-8237 Tihany, Hungary.
| | - Thomas Mehner
- Leibniz Institute of Freshwater Ecology and Inland Fisheries, Müggelseedamm 310, D-12587 Berlin, Germany.
| | - Mikko Olin
- Natural Resources Institute Finland, P. O. Box 2, FI-00791 Helsinki, Finland.
| | - Graeme Peirson
- Environment Agency, Research, Analysis and Evaluation, Air, Land and Water Team, Worcester Road, Kidderminster DY11 RA, United Kingdom.
| | - Pietro Volta
- CNR Water Research Institute (IRSA), L.go Tonolli 50, 28922 Verbania Pallanza, Italy.
| | - Sandra Poikane
- European Commission Joint Research Centre (JRC), Via Enrico Fermi 274, 21027 Ispra, VA, Italy.
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13
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Holubová M, Hejzlar J, Čech M, Vašek M, Blabolil P, Peterka J. Fluctuations in pelagic fish density linked to ambient conditions. J Fish Biol 2021; 98:756-767. [PMID: 33219532 DOI: 10.1111/jfb.14622] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Accepted: 11/19/2020] [Indexed: 06/11/2023]
Abstract
Animal behaviour has been broadly studied for its social or functional aspects but less often for understanding the interactions between organisms and their ambient conditions. A pilot observational study was performed by means of underwater camera to investigate the correlation between environmental factors and the density of fish in the epipelagic habitat of a European temperate reservoir. Explored factors confirmed a positive correlation between water temperature and all observed categories: nonpredatory, predatory, single nonpredatory and schooling fish, as well as freshwater bream and roach. On the other hand, de-trended solar irradiance was found to be negatively correlated with density of nonpredatory fish, freshwater bream and European perch. Sunshine duration was negatively correlated with the density of predatory fish. Precipitation a showed positive relationship with single nonpredatory fish and European perch, whereas wind strength had a negative relationship with density of schooling fish. Furthermore, density of predatory fish was positively correlated with density of single nonpredatory fish and counts of observed clusters. Altogether, findings indicate that fish density is correlated with abiotic factors and the occurrence of predators. This suggests that more ecologically complex studies should be encouraged for better understanding of ecological interactions that drive the structure of aquatic ecosystems.
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Affiliation(s)
- Michaela Holubová
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, České Budějovice, Czech Republic
- Faculty of Science, University of South Bohemia, České Budějovice, Czech Republic
| | - Josef Hejzlar
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, České Budějovice, Czech Republic
| | - Martin Čech
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, České Budějovice, Czech Republic
| | - Mojmír Vašek
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, České Budějovice, Czech Republic
| | - Petr Blabolil
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, České Budějovice, Czech Republic
- Faculty of Science, University of South Bohemia, České Budějovice, Czech Republic
| | - Jiří Peterka
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, České Budějovice, Czech Republic
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14
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Šmejkal M, Bartoň D, Brabec M, Sajdlová Z, Souza AT, Moraes KR, Soukalová K, Blabolil P, Vejřík L, Kubečka J. Climbing up the ladder: male reproductive behaviour changes with age in a long-lived fish. Behav Ecol Sociobiol 2021. [DOI: 10.1007/s00265-020-02961-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Abstract
High reproductive performance is the key attribute of male fitness, especially due to the high reproductive skew among the males of most animal species. Males of long-lived iteroparous species have opportunities to improve upon their previous reproductive attempts with increasing age. We collected individual-specific reproductive behaviour and age data on a cyprinid fish, the asp (Leuciscus aspius), from 2015 to 2019. We tested whether males changed their performance over time using a unique dataset where individual performance was recorded yearly with passive telemetry. Individual fish behaviour was tracked from one to five reproductive seasons at least a year after the tagging. Fish were scored by measures of quality (first arrival time, number of visits and time spent in the reproductive grounds, and encountered proportion of males to all adult fish). In general, fish improved in the first three metrics with age, suggesting a shift towards behaviours likely to enhance reproductive success as individuals aged. A larger size at tagging was predictive of earlier fish arrival on the spawning ground in subsequent years. Our study therefore demonstrates the importance of age as a factor when considering the potential reproductive success of long-lived fish species.
Significance statement
High reproductive performance is the key attribute of male fitness. Males of long-lived species reproducing multiple times in their life have opportunities to improve upon their previous reproductive performance with increasing age. In this 5-year study, we tracked a large cyprinid fish with telemetry systems during their reproduction. We investigated the age-related behavioural changes in males and demonstrated the improvement of male reproductive timing and length of stay with potential repercussions for male’s reproductive output. We emphasize the importance of old and experienced individuals among the fish population, which are often targeted and selectively removed from the human-managed waters.
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15
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Antón-Pardo M, Muška M, Jůza T, Vejříková I, Vejřík L, Blabolil P, Čech M, Draštík V, Frouzová J, Holubová M, Říha M, Sajdlová Z, Šmejkal M, Peterka J. Diel changes in vertical and horizontal distribution of cladocerans in two deep lakes during early and late summer. Sci Total Environ 2021; 751:141601. [PMID: 32871313 DOI: 10.1016/j.scitotenv.2020.141601] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2020] [Revised: 07/17/2020] [Accepted: 08/08/2020] [Indexed: 06/11/2023]
Abstract
Temporal and spatial heterogeneity in the distribution of cladocerans in lakes could be caused by abiotic (wind, water currents) and biotic factors (reproduction, food resources, predation). Diel horizontal and vertical distribution of cladoceran assemblages was studied in two deep lakes (Milada and Most Lakes, Czech Republic) in early (June) and late (September) summer. The objective was to study diel vertical migration (DVM) and diel horizontal migration (DHM) of cladocerans under conditions of different macrophyte cover in littoral areas (rich in Milada Lake, poor in Most Lake) and fish assemblages (non-specialised planktivorous species in Milada Lake, and abundant planktivorous fish - maraena whitefish, Coregonus maraena - in open water habitats in Most Lake). Temporal variations in cladoceran assemblages were reported in both lakes in the two sampling periods. DVM was observed in the two lakes, performed by the most vulnerable species to fish predation (the larger Daphnia spp.), but with different patterns (direct and reverse) probably linked with the local fish community and other biotic and abiotic factors in each lake. Horizontal movements were only observed in Most Lake: D. longispina increase its abundance in open waters at night compared to the littoral points; while Ceriodaphnia spp. showed the inverse pattern. In both lakes, higher densities were often found at night in surface layers, producing a great "diurnal deficit": cladocerans remain undetected in some zones during the day (especially in the littoral areas) moving to surface layers at night.
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Affiliation(s)
- María Antón-Pardo
- GRECO, Institute of Aquatic Ecology, University of Girona, Campus Montilivi, Faculty of Sciences, E-17071 Girona, Spain; Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, České Budějovice, Czech Republic.
| | - Milan Muška
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, České Budějovice, Czech Republic
| | - Tomáš Jůza
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, České Budějovice, Czech Republic
| | - Ivana Vejříková
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, České Budějovice, Czech Republic
| | - Lukáš Vejřík
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, České Budějovice, Czech Republic
| | - Petr Blabolil
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, České Budějovice, Czech Republic
| | - Martin Čech
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, České Budějovice, Czech Republic
| | - Vladislav Draštík
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, České Budějovice, Czech Republic
| | - Jaroslava Frouzová
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, České Budějovice, Czech Republic
| | - Michaela Holubová
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, České Budějovice, Czech Republic
| | - Milan Říha
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, České Budějovice, Czech Republic
| | - Zuzana Sajdlová
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, České Budějovice, Czech Republic
| | - Marek Šmejkal
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, České Budějovice, Czech Republic
| | - Jiří Peterka
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, České Budějovice, Czech Republic
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16
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Lisnerova M, Blabolil P, Holzer A, Jurajda P, Fiala I. Myxozoan hidden diversity: the case of Myxobolus pseudodispar Gorbunova, 1936. Folia Parasitol (Praha) 2020; 67. [PMID: 32764187 DOI: 10.14411/fp.2020.019] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2019] [Accepted: 04/07/2020] [Indexed: 01/04/2023]
Abstract
Myxobolus pseudodispar Gorbunova, 1936 (Myxozoa) was originally described as a parasite of common roach, Rutilus rutilus (Linnaeus), with developing stages in muscles and spores disseminated in macrophage centres of different organs and tissues. Later, this parasite was described from several other cyprinids, but with relatively large intraspecific differences based on SSU rDNA gene sequences. Within our long-term study on myxozoan biodiversity, we performed a broad microscopic and molecular screening of various freshwater fish species (over 450 specimens, 36 species) from different localities. We investigated the cryptic species status of M. pseudodispar. Our analysis revealed four new unique SSU rDNA sequences of M. pseudodispar as well as an infection in new fish host species. Myxobolus pseudodispar sequence analysis showed clear phylogenetic grouping according to fish host criterion forming 13 well-recognised clades. Using 1% SSU rDNA-based genetic distance criterion, at least ten new species of Myxobolus Bütschli, 1882 may be recognised in the group of M. pseudodispar sequences. Our analysis showed the paraphyletic character of M. pseudodispar sequences and the statistical tests rejected hypothetical tree topology with the monophyletic status of the M. pseudodispar group. Myxobolus pseudodispar represents a species complex and it is a typical example of myxozoan hidden diversity phenomenon confirming myxozoans as an evolutionary very successful group of parasites with a great ability to adapt to a new hosts with subsequent speciation events.
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Affiliation(s)
- Martina Lisnerova
- Institute of Parasitology, Biology Centre of the Czech Academy of Sciences, Ceske Budejovice, Czech Republic.,Department of Parasitology, Faculty of Sciences, University of South Bohemia, Ceske Budejovice, Czech Republic
| | - Petr Blabolil
- Institute of Hydrobiology, Biology Centre of the Czech Academy of Sciences, Ceske Budejovice, Czech Republic
| | - Astrid Holzer
- Institute of Parasitology, Biology Centre of the Czech Academy of Sciences, Ceske Budejovice, Czech Republic
| | - Pavel Jurajda
- Institute of Vertebrate Biology of the Czech Academy of Sciences, Brno, Czech Republic
| | - Ivan Fiala
- Institute of Parasitology, Biology Centre of the Czech Academy of Sciences, Ceske Budejovice, Czech Republic.,Department of Parasitology, Faculty of Sciences, University of South Bohemia, Ceske Budejovice, Czech Republic
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17
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Holubová M, Blabolil P, Čech M, Vašek M, Peterka J. Species-specific schooling behaviour of fish in the freshwater pelagic habitat: an observational study. J Fish Biol 2020; 97:64-74. [PMID: 32189344 DOI: 10.1111/jfb.14326] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2019] [Revised: 03/12/2020] [Accepted: 03/17/2020] [Indexed: 06/10/2023]
Abstract
Social living of animals is a broadly occurring phenomenon, although poorly studied in freshwater systems, fish schooling behaviour is an excellent example. The composition of fish schools, species-specific schooling tendencies and preferences of adult fish were studied in the pelagic habitat of the Římov Reservoir, Czech Republic. Video recordings captured over a total of 34 days (16 h per day) in the clear water period of three seasons were analysed. From four species identified as school-forming species - bream, bleak, roach and perch, 40% of the individuals observed formed schools of 3-36 individuals. Although conspecific schools prevailed, 20% of individuals formed heterospecific schools, except bleak that schooled strictly with conspecifics. Schools were composed of individuals of similar body size and life strategy. Heterospecific schools were significantly larger than conspecific schools and showed uneven proportion among species, that is, one species being more abundant when the school dimension increased. Probability of encounter in bleak was lowest and proved highest inclination for schooling. Gregarianism levels depended on species morphology and body size, with larger and morphologically advanced fish tending less to sociability. This indicates that the antipredator function of schooling behaviour is intensified with increasing vulnerability of the species.
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Affiliation(s)
- Michaela Holubová
- Institute of Hydrobiology, Biology Centre of the Czech Academy of Sciences, České Budějovice, Czech Republic
- Faculty of Science, University of South Bohemia, České Budějovice, Czech Republic
| | - Petr Blabolil
- Institute of Hydrobiology, Biology Centre of the Czech Academy of Sciences, České Budějovice, Czech Republic
| | - Martin Čech
- Institute of Hydrobiology, Biology Centre of the Czech Academy of Sciences, České Budějovice, Czech Republic
| | - Mojmír Vašek
- Institute of Hydrobiology, Biology Centre of the Czech Academy of Sciences, České Budějovice, Czech Republic
| | - Jiří Peterka
- Institute of Hydrobiology, Biology Centre of the Czech Academy of Sciences, České Budějovice, Czech Republic
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18
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Šmejkal M, Bartoň D, Děd V, Souza AT, Blabolil P, Vejřík L, Sajdlová Z, Říha M, Kubečka J. Negative feedback concept in tagging: Ghost tags imperil the long-term monitoring of fishes. PLoS One 2020; 15:e0229350. [PMID: 32119687 PMCID: PMC7051092 DOI: 10.1371/journal.pone.0229350] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2020] [Accepted: 02/04/2020] [Indexed: 11/18/2022] Open
Abstract
Wildlife monitoring using passive telemetry has become a robust method for investigating animal migration. With increased use, this method progressively pollutes the environment with technological waste represented by so called ghost tags (PIT tags ending in the environment due to reproductive expulsions, shedding or animal mortality). However, their presence in the environment may lead to failed detections of living individuals. We used tagging data from studies of the asp Leuciscus aspius and the bleak Alburnus alburnus collected from 2014 to 2018 and located ghost tag positions on the monitored spawning site using portable backpack reader for their detection. We modelled virtual river-wide flat-bed antennas (widths 0.2, 0.4, 0.6 and 0.8 m) representing monitoring effort and estimated the probability of the presence of ghost tags within the antenna field. Of 3724 PIT tags used in the study, we detected on the spawning ground 173 ghost tags originating from long-term monitoring. The ghost tags accumulated in the environment in time, suggesting insufficient degradation rate or shift downstream from the research site. Number of ghost tags present on the spawning ground led to high probability of disabled readings of tagged fish passing through the antenna electro-magnetic field. We demonstrate how accumulated ghost tags may cause detection failures for focal species and incomplete data acquisition. We infer that intensive long-term monitoring using PIT tag technology may encumber future data acquisition or entail additional costs for clean-up.
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Affiliation(s)
- Marek Šmejkal
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, České Budějovice, Czech Republic
- * E-mail:
| | - Daniel Bartoň
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, České Budějovice, Czech Republic
| | - Vilém Děd
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, České Budějovice, Czech Republic
| | - Allan T. Souza
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, České Budějovice, Czech Republic
| | - Petr Blabolil
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, České Budějovice, Czech Republic
| | - Lukáš Vejřík
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, České Budějovice, Czech Republic
| | - Zuzana Sajdlová
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, České Budějovice, Czech Republic
| | - Milan Říha
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, České Budějovice, Czech Republic
| | - Jan Kubečka
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, České Budějovice, Czech Republic
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19
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Vejřík L, Vejříková I, Kočvara L, Blabolil P, Peterka J, Sajdlová Z, Jůza T, Šmejkal M, Kolařík T, Bartoň D, Kubečka J, Čech M. The pros and cons of the invasive freshwater apex predator, European catfish Silurus glanis, and powerful angling technique for its population control. J Environ Manage 2019; 241:374-382. [PMID: 31026726 DOI: 10.1016/j.jenvman.2019.04.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2018] [Revised: 03/30/2019] [Accepted: 04/05/2019] [Indexed: 06/09/2023]
Abstract
Catfish have spread across Europe and several countries out of this region within the last decades. Basic knowledge of this apex predator has revealed concerns of invasive behaviour and questions regarding its utilization as a biomanipulation species. However, a method enabling its regulation to a required level has not yet been developed. We simulated the impact of angling on the catfish population by method of hook-lines in two post-mining lakes with a monitored population consisting of tagged individuals and in two reservoirs as reference sites. Further, the efficiency of hook-lines as a reducing device was examined and the economic aspects were determined. Catfish population in localities where the species is unwanted or invasive may be efficiently reduced to a harmless level by hook-lines and angling (depending on the approach of anglers). The most efficient time of the year seems to be spring to early summer with catch efficiency of 5.4 individuals per 10 baits in one day. The catch efficiency markedly decreased during the second part of the year and did not exceed 2.8 individuals per 10 baits in one day. Mean size of catfish had negative impact whereas catfish biomass had positive impact on the catch efficiency. Trophic status and number of catfish in the locality had no impact on the catch efficiency. According to model, 11-18 bait-days per 1 ha per season is efficient to decrease catfish population to 10% of the original size. Both angling and hook-lines are very simple, they are financially and time bearable mechanisms of catfish regulation in any condition. However, catfish play an important role as a biomanipulative species in many localities. In this case where catfish is beneficial, angling presents a real threat of population collapse and loss of the biomanipulative effect.
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Affiliation(s)
- Lukáš Vejřík
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, Na Sádkách 7, 37005, České Budějovice, Czech Republic; University of South Bohemia in České Budějovice, Faculty of Science, Branišovská 31, 37005, České Budějovice, Czech Republic.
| | - Ivana Vejříková
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, Na Sádkách 7, 37005, České Budějovice, Czech Republic
| | - Luboš Kočvara
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, Na Sádkách 7, 37005, České Budějovice, Czech Republic
| | - Petr Blabolil
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, Na Sádkách 7, 37005, České Budějovice, Czech Republic
| | - Jiří Peterka
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, Na Sádkách 7, 37005, České Budějovice, Czech Republic
| | - Zuzana Sajdlová
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, Na Sádkách 7, 37005, České Budějovice, Czech Republic
| | - Tomáš Jůza
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, Na Sádkách 7, 37005, České Budějovice, Czech Republic
| | - Marek Šmejkal
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, Na Sádkách 7, 37005, České Budějovice, Czech Republic
| | - Tomáš Kolařík
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, Na Sádkách 7, 37005, České Budějovice, Czech Republic
| | - Daniel Bartoň
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, Na Sádkách 7, 37005, České Budějovice, Czech Republic
| | - Jan Kubečka
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, Na Sádkách 7, 37005, České Budějovice, Czech Republic
| | - Martin Čech
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, Na Sádkách 7, 37005, České Budějovice, Czech Republic
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20
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Šmejkal M, Souza AT, Blabolil P, Bartoň D, Sajdlová Z, Vejřík L, Kubečka J. Nocturnal spawning as a way to avoid egg exposure to diurnal predators. Sci Rep 2018; 8:15377. [PMID: 30337666 PMCID: PMC6193928 DOI: 10.1038/s41598-018-33615-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2018] [Accepted: 10/03/2018] [Indexed: 11/25/2022] Open
Abstract
Animals that do not provide parental care have to secure the survival of their offspring by ensuring a safe reproductive environment or smart timing tactics. Nocturnal spawning behaviour of many fish species is an example of the latter behaviour in the animal kingdom and is hypothesized to provide a survival advantage to the eggs spawned during the night. In order to test the efficiency of the smart timing tactics in a freshwater fish, a study was carried out of the interaction of the rheophilic spawner (asp Leuciscus aspius) and the predator of its drifting eggs (bleak Alburnus alburnus) using passive telemetry. According to a model based on acquired data, asp laid 63% of its eggs at night, while vision-oriented bleak was present in 92% of the time during the day. This study gives support to the predator avoidance hypothesis, which expects animals to reproduce in a period when the probability of offspring predation is at its lowest.
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Affiliation(s)
- Marek Šmejkal
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, České Budějovice, Czech Republic. .,Biology Centre of the Czech Academy of Sciences, SOWA, České Budějovice, Czech Republic.
| | - Allan T Souza
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, České Budějovice, Czech Republic
| | - Petr Blabolil
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, České Budějovice, Czech Republic.,Biology Centre of the Czech Academy of Sciences, SOWA, České Budějovice, Czech Republic
| | - Daniel Bartoň
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, České Budějovice, Czech Republic
| | - Zuzana Sajdlová
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, České Budějovice, Czech Republic
| | - Lukáš Vejřík
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, České Budějovice, Czech Republic.,Biology Centre of the Czech Academy of Sciences, SOWA, České Budějovice, Czech Republic
| | - Jan Kubečka
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, České Budějovice, Czech Republic
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21
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Žák J, Jůza T, Blabolil P, Baran R, Bartoň D, Draštík V, Frouzová J, Holubová M, Ketelaars HAM, Kočvara L, Kubečka J, Mrkvička T, Muška M, Říha M, Sajdlová Z, Šmejkal M, Tušer M, Vašek M, Vejřík L, Vejříková I, Wagenvoort AJ. Invasive round goby Neogobius melanostomus has sex-dependent locomotor activity and is under-represented in catches from passive fishing gear compared with seine catches. J Fish Biol 2018; 93:147-152. [PMID: 29931676 DOI: 10.1111/jfb.13646] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2018] [Accepted: 05/08/2018] [Indexed: 06/08/2023]
Abstract
The higher proportion of males of the invasive round goby Neogobius melanostomus in samples from two activity selective passive fishing gears compared with one activity non-selective fishing gear in three Dutch lakes is related to higher male locomotory activity and is a sex-dependent trait. This difference in activity reflects the different ecology of male and female N. melanostomus.
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Affiliation(s)
- Jakub Žák
- Institute of Hydrobiology, Biology Centre of the Czech Academy of Sciences, České Budějovice, Czech Republic
- Department of Zoology, Faculty of Science, Charles University, Prague, Czech Republic
| | - Tomáš Jůza
- Institute of Hydrobiology, Biology Centre of the Czech Academy of Sciences, České Budějovice, Czech Republic
| | - Petr Blabolil
- Institute of Hydrobiology, Biology Centre of the Czech Academy of Sciences, České Budějovice, Czech Republic
| | - Roman Baran
- Institute of Hydrobiology, Biology Centre of the Czech Academy of Sciences, České Budějovice, Czech Republic
| | - Daniel Bartoň
- Institute of Hydrobiology, Biology Centre of the Czech Academy of Sciences, České Budějovice, Czech Republic
| | - Vladislav Draštík
- Institute of Hydrobiology, Biology Centre of the Czech Academy of Sciences, České Budějovice, Czech Republic
| | - Jaroslava Frouzová
- Institute of Hydrobiology, Biology Centre of the Czech Academy of Sciences, České Budějovice, Czech Republic
| | - Michaela Holubová
- Institute of Hydrobiology, Biology Centre of the Czech Academy of Sciences, České Budějovice, Czech Republic
| | | | - Luboš Kočvara
- Institute of Hydrobiology, Biology Centre of the Czech Academy of Sciences, České Budějovice, Czech Republic
| | - Jan Kubečka
- Institute of Hydrobiology, Biology Centre of the Czech Academy of Sciences, České Budějovice, Czech Republic
| | - Tomáš Mrkvička
- Institute of Hydrobiology, Biology Centre of the Czech Academy of Sciences, České Budějovice, Czech Republic
- Faculty of Economics, University of South Bohemia, České Budějovice, Czech Republic
| | - Milan Muška
- Institute of Hydrobiology, Biology Centre of the Czech Academy of Sciences, České Budějovice, Czech Republic
| | - Milan Říha
- Institute of Hydrobiology, Biology Centre of the Czech Academy of Sciences, České Budějovice, Czech Republic
| | - Zuzana Sajdlová
- Institute of Hydrobiology, Biology Centre of the Czech Academy of Sciences, České Budějovice, Czech Republic
| | - Marek Šmejkal
- Institute of Hydrobiology, Biology Centre of the Czech Academy of Sciences, České Budějovice, Czech Republic
| | - Michal Tušer
- Institute of Hydrobiology, Biology Centre of the Czech Academy of Sciences, České Budějovice, Czech Republic
| | - Mojmír Vašek
- Institute of Hydrobiology, Biology Centre of the Czech Academy of Sciences, České Budějovice, Czech Republic
| | - Lukáš Vejřík
- Institute of Hydrobiology, Biology Centre of the Czech Academy of Sciences, České Budějovice, Czech Republic
| | - Ivana Vejříková
- Institute of Hydrobiology, Biology Centre of the Czech Academy of Sciences, České Budějovice, Czech Republic
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22
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Šmejkal M, Ricard D, Sajdlová Z, Čech M, Vejřík L, Blabolil P, Vejříková I, Prchalová M, Vašek M, Souza AT, Brönmark C, Peterka J. Can species-specific prey responses to chemical cues explain prey susceptibility to predation? Ecol Evol 2018; 8:4544-4551. [PMID: 29760895 PMCID: PMC5938473 DOI: 10.1002/ece3.4000] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2017] [Revised: 01/26/2018] [Accepted: 02/23/2018] [Indexed: 11/10/2022] Open
Abstract
The perception of danger represents an essential ability of prey for gaining an informational advantage over their natural enemies. Especially in complex environments or at night, animals strongly rely on chemoreception to avoid predators. The ability to recognize danger by chemical cues and subsequent adaptive responses to predation threats should generally increase prey survival. Recent findings suggest that European catfish (Silurus glanis) introduction induce changes in fish community and we tested whether the direction of change can be attributed to differences in chemical cue perception. We tested behavioral response to chemical cues using three species of freshwater fish common in European water: rudd (Scardinius erythrophthalmus), roach (Rutilus rutilus), and perch (Perca fluviatilis). Further, we conducted a prey selectivity experiment to evaluate the prey preferences of the European catfish. Roach exhibited the strongest reaction to chemical cues, rudd decreased use of refuge and perch did not alter any behavior in the experiment. These findings suggest that chemical cue perception might be behind community data change and we encourage collecting more community data of tested prey species before and after European catfish introduction to test the hypothesis. We conclude that used prey species can be used as a model species to verify whether chemical cue perception enhances prey survival.
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Affiliation(s)
- Marek Šmejkal
- Biology Centre of the Academy of Sciences of the Czech Republic Institute of Hydrobiology České Budějovice Czech Republic.,Faculty of Science University of South Bohemia České Budějovice Czech Republic
| | - Daniel Ricard
- Biology Centre of the Academy of Sciences of the Czech Republic Institute of Hydrobiology České Budějovice Czech Republic.,Fisheries and Oceans Canada Gulf Fisheries Centre Moncton Canada
| | - Zuzana Sajdlová
- Biology Centre of the Academy of Sciences of the Czech Republic Institute of Hydrobiology České Budějovice Czech Republic
| | - Martin Čech
- Biology Centre of the Academy of Sciences of the Czech Republic Institute of Hydrobiology České Budějovice Czech Republic
| | - Lukáš Vejřík
- Biology Centre of the Academy of Sciences of the Czech Republic Institute of Hydrobiology České Budějovice Czech Republic
| | - Petr Blabolil
- Biology Centre of the Academy of Sciences of the Czech Republic Institute of Hydrobiology České Budějovice Czech Republic
| | - Ivana Vejříková
- Biology Centre of the Academy of Sciences of the Czech Republic Institute of Hydrobiology České Budějovice Czech Republic
| | - Marie Prchalová
- Biology Centre of the Academy of Sciences of the Czech Republic Institute of Hydrobiology České Budějovice Czech Republic
| | - Mojmír Vašek
- Biology Centre of the Academy of Sciences of the Czech Republic Institute of Hydrobiology České Budějovice Czech Republic
| | - Allan T Souza
- Biology Centre of the Academy of Sciences of the Czech Republic Institute of Hydrobiology České Budějovice Czech Republic
| | | | - Jiří Peterka
- Biology Centre of the Academy of Sciences of the Czech Republic Institute of Hydrobiology České Budějovice Czech Republic
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23
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Blabolil P, Duras J, Jůza T, Kočvara L, Matěna J, Muška M, Říha M, Vejřík L, Holubová M, Peterka J. Assessment of burbot Lota lota (L. 1758) population sustainability in central European reservoirs. J Fish Biol 2018; 92:1545-1559. [PMID: 29635683 DOI: 10.1111/jfb.13610] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2017] [Revised: 02/19/2018] [Accepted: 02/28/2018] [Indexed: 06/08/2023]
Abstract
A novel sampling scheme, using a combination of electrofishing, visual exploration by scuba divers, two types of fyke nets and longlines, was tested in four reservoirs (including their inlets and outlets) to monitor a population of burbot Lota lota. This was supplemented by fry trawling and vertical hydro-acoustics, to detect L. lota larvae in two deep reservoirs that have had a long-term stocking programme. The majority of the L. lota detected were juveniles, captured by electrofishing in the littoral zones of the reservoirs and in running waters. Older individuals were rarely captured with longlines or fyke nets in deeper zones or structured habitats within the reservoirs. A combination of multiple sampling methods provided an assessment of the whole population. Population establishment could not be demonstrated as the age structure of the sampled fish corresponded with that of the stocked fish. Low post-stocking survival, migratory behaviour, interactions with other species and warmer water temperatures are considered the potential drivers for unsuccessful establishment of L. lota populations in these reservoirs.
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Affiliation(s)
- P Blabolil
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, Na Sádkách 7, 370 05, České Budějovice, Czech Republic
| | - J Duras
- Faculty of Fisheries and Protection of Waters, South Bohemian Research Center of Aquaculture and Biodiversity of Hydrocenoses, Institute of Aquaculture and Protection of Waters, University of South Bohemia in České Budějovice, Husova tř. 458/102, 370 05, České Budějovice, Czech Republic
| | - T Jůza
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, Na Sádkách 7, 370 05, České Budějovice, Czech Republic
| | - L Kočvara
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, Na Sádkách 7, 370 05, České Budějovice, Czech Republic
| | - J Matěna
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, Na Sádkách 7, 370 05, České Budějovice, Czech Republic
| | - M Muška
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, Na Sádkách 7, 370 05, České Budějovice, Czech Republic
| | - M Říha
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, Na Sádkách 7, 370 05, České Budějovice, Czech Republic
| | - L Vejřík
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, Na Sádkách 7, 370 05, České Budějovice, Czech Republic
| | - M Holubová
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, Na Sádkách 7, 370 05, České Budějovice, Czech Republic
| | - J Peterka
- Biology Centre of the Czech Academy of Sciences, Institute of Hydrobiology, Na Sádkách 7, 370 05, České Budějovice, Czech Republic
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24
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Baran R, Jůza T, Tušer M, Balk H, Blabolil P, Čech M, Draštík V, Frouzová J, Jayasinghe AD, Koliada I, Mrkvička T, Muška M, Ricard D, Sajdlová Z, Vejřík L, Kubečka J. A novel upward-looking hydroacoustic method for improving pelagic fish surveys. Sci Rep 2017; 7:4823. [PMID: 28684758 PMCID: PMC5500586 DOI: 10.1038/s41598-017-04953-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2017] [Accepted: 05/23/2017] [Indexed: 12/02/2022] Open
Abstract
For ethical reasons and animal welfare, it is becoming increasingly more important to carry out ecological surveys with a non-invasive approach. Information about fish distribution and abundance in the upper water column is often fundamental. However, this information is extremely hard to obtain using classical hydroacoustic methods. We developed a rigid frame system for pushing upward looking transducers of the scientific echo sounder (38 and 120 kHz) in front of the research vessel. The efficiency of the new approach for monitoring juvenile fish at night was investigated by comparing the results with a quantitative fry trawl in the Římov Reservoir in the Czech Republic. The experimental setup enabled comparisons for the 0-3 m and 3-6 m depth layers, which are utilized by almost all juvenile fish in summer. No statistically significant differences in the estimated abundance of juveniles were found between the two sampling methods. The comparison of abundance estimates gathered by the two frequencies were also not significantly different. The predicted mean lengths from acoustic sampling and the trawl catches differed by less than 10 mm in all comparisons. Results suggest that mobile hydroacoustic upward-looking systems can fill the methodological gap in non-invasive surveying of surface fishes.
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Affiliation(s)
- Roman Baran
- Institute of Hydrobiology, Biology centre of the Czech Academy of Sciences, České Budějovice, Czech Republic
- Faculty of Science, University of South Bohemia, České Budějovice, Czech Republic
| | - Tomáš Jůza
- Institute of Hydrobiology, Biology centre of the Czech Academy of Sciences, České Budějovice, Czech Republic
| | - Michal Tušer
- Institute of Hydrobiology, Biology centre of the Czech Academy of Sciences, České Budějovice, Czech Republic
| | - Helge Balk
- Institute of Hydrobiology, Biology centre of the Czech Academy of Sciences, České Budějovice, Czech Republic
- Department of Physics, University of Oslo, Oslo, Norway
| | - Petr Blabolil
- Institute of Hydrobiology, Biology centre of the Czech Academy of Sciences, České Budějovice, Czech Republic
| | - Martin Čech
- Institute of Hydrobiology, Biology centre of the Czech Academy of Sciences, České Budějovice, Czech Republic
| | - Vladislav Draštík
- Institute of Hydrobiology, Biology centre of the Czech Academy of Sciences, České Budějovice, Czech Republic
| | - Jaroslava Frouzová
- Institute of Hydrobiology, Biology centre of the Czech Academy of Sciences, České Budějovice, Czech Republic
| | - Asanka D Jayasinghe
- Institute of Hydrobiology, Biology centre of the Czech Academy of Sciences, České Budějovice, Czech Republic
- Department of Limnology, University of Ruhuna, Wellamadama, Matara, Sri Lanka
| | - Ievgen Koliada
- Institute of Hydrobiology, Biology centre of the Czech Academy of Sciences, České Budějovice, Czech Republic
| | - Tomáš Mrkvička
- Institute of Hydrobiology, Biology centre of the Czech Academy of Sciences, České Budějovice, Czech Republic
- Faculty of Economics, University of South Bohemia, České Budějovice, Czech Republic
| | - Milan Muška
- Institute of Hydrobiology, Biology centre of the Czech Academy of Sciences, České Budějovice, Czech Republic
| | - Daniel Ricard
- Institute of Hydrobiology, Biology centre of the Czech Academy of Sciences, České Budějovice, Czech Republic
- Fisheries and Oceans Canada, Gulf Fisheries Centre, Moncton, Canada
| | - Zuzana Sajdlová
- Institute of Hydrobiology, Biology centre of the Czech Academy of Sciences, České Budějovice, Czech Republic
| | - Lukáš Vejřík
- Institute of Hydrobiology, Biology centre of the Czech Academy of Sciences, České Budějovice, Czech Republic
| | - Jan Kubečka
- Institute of Hydrobiology, Biology centre of the Czech Academy of Sciences, České Budějovice, Czech Republic.
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25
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Poikane S, Ritterbusch D, Argillier C, Białokoz W, Blabolil P, Breine J, Jaarsma NG, Krause T, Kubečka J, Lauridsen TL, Nõges P, Peirson G, Virbickas T. Response of fish communities to multiple pressures: Development of a total anthropogenic pressure intensity index. Sci Total Environ 2017; 586:502-511. [PMID: 28214116 PMCID: PMC6461715 DOI: 10.1016/j.scitotenv.2017.01.211] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2016] [Revised: 01/27/2017] [Accepted: 01/27/2017] [Indexed: 05/26/2023]
Abstract
Lakes in Europe are subject to multiple anthropogenic pressures, such as eutrophication, habitat degradation and introduction of alien species, which are frequently inter-related. Therefore, effective assessment methods addressing multiple pressures are needed. In addition, these systems have to be harmonised (i.e. intercalibrated) to achieve common management objectives across Europe. Assessments of fish communities inform environmental policies on ecological conditions integrating the impacts of multiple pressures. However, the challenge is to ensure consistency in ecological assessments through time, across ecosystem types and across jurisdictional boundaries. To overcome the serious comparability issues between national assessment systems in Europe, a total anthropogenic pressure intensity (TAPI) index was developed as a weighted combination of the most common pressures in European lakes that is validated against 10 national fish-based water quality assessment systems using data from 556 lakes. Multi-pressure indices showed significantly higher correlations with fish indices than single-pressure indices. The best-performing index combines eutrophication, hydromorphological alterations and human use intensity of lakes. For specific lake types also biological pressures may constitute an important additional pressure. The best-performing index showed a strong correlation with eight national fish-based assessment systems. This index can be used in lake management for assessing total anthropogenic pressure on lake ecosystems and creates a benchmark for comparison of fish assessments independent of fish community composition, size structure and fishing-gear. We argue that fish-based multiple-pressure assessment tools should be seen as complementary to single-pressure tools offering the major advantage of integrating direct and indirect effects of multiple pressures over large scales of space and time.
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Affiliation(s)
- Sandra Poikane
- European Commission Joint Research Centre, Directorate for Sustainable Resources, Water and Marine Resources Unit, I-21027 Ispra, VA, Italy.
| | - David Ritterbusch
- Institute of Inland Fisheries, Im Königswald 2, 14469 Potsdam-Sacrow, Germany
| | - Christine Argillier
- Irstea, UR RECOVER, 3275 Route de Cézanne CS 40061, 13182 Aix en Provence Cedex 5, France
| | - Witold Białokoz
- Inland Fisheries Institute, Oczapowskiego 10-719, Olsztyn, Poland
| | - Petr Blabolil
- Institute of Hydrobiology, Biology Centre of the Czech Academy of Sciences, Na Sádkách 7, 370 05 České Budějovice, Czech Republic; Faculty of Science, University of South Bohemia, Branišovská 31, 370 05 České Budějovice, Czech Republic
| | - Jan Breine
- Research Institute for Nature and Forest, Dwersbos 28, B-1630 Linkebeek, Belgium
| | | | - Teet Krause
- Centre for Limnology, Institute of Agricultural and Environmental Sciences, Estonian University of Life Sciences, Kreutzwaldi 5, 51014 Tartu, Estonia
| | - Jan Kubečka
- Institute of Hydrobiology, Biology Centre of the Czech Academy of Sciences, Na Sádkách 7, 370 05 České Budějovice, Czech Republic
| | - Torben L Lauridsen
- Department of Bioscience, Aarhus University, Vejlsøvej 25, 8600 Silkeborg, Denmark
| | - Peeter Nõges
- Centre for Limnology, Institute of Agricultural and Environmental Sciences, Estonian University of Life Sciences, Kreutzwaldi 5, 51014 Tartu, Estonia
| | | | - Tomas Virbickas
- Nature Research Centre, Akademijos 2, LT-08412 Vilnius-21, Lithuania
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26
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Matěna J, Matěnová V, Blabolil P, Kopáček J, Peltanová J, Šorf M, Žaloudík J, Vrba J. Recovery of brown trout populations in streams exposed to atmospheric acidification in the Bohemian Forest. Folia Zoologica 2017. [DOI: 10.25225/fozo.v66.i1.a2.2017] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- Josef Matěna
- Institute of Hydrobiology, Biology Centre CAS, Na Sádkách 7, 370 05 České Budějovice, Czech Republic
| | - Vlasta Matěnová
- Faculty of Education, University of South Bohemia, Jeronýmova 10, 371 15 České Budějovice, Czech Republic
| | - Petr Blabolil
- Institute of Hydrobiology, Biology Centre CAS, Na Sádkách 7, 370 05 České Budějovice, Czech Republic
| | - Jiří Kopáček
- Institute of Hydrobiology, Biology Centre CAS, Na Sádkách 7, 370 05 České Budějovice, Czech Republic
| | - Jana Peltanová
- Faculty of Science, University of South Bohemia, Branišovská 1760, 370 05 České Budějovice, Czech Republic
| | - Michal Šorf
- Faculty of Science, University of South Bohemia, Branišovská 1760, 370 05 České Budějovice, Czech Republic
| | - Jiří Žaloudík
- Institute of Hydrobiology, Biology Centre CAS, Na Sádkách 7, 370 05 České Budějovice, Czech Republic
| | - Jaroslav Vrba
- Institute of Hydrobiology, Biology Centre CAS, Na Sádkách 7, 370 05 České Budějovice, Czech Republic
- Faculty of Science, University of South Bohemia, Branišovská 1760, 370 05 České Budějovice, Czech Republic
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Vejřík L, Matějíčková I, Seďa J, Blabolil P, Jůza T, Vašek M, Ricard D, Matěna J, Frouzová J, Kubečka J, Říha M, Čech M. Who Is Who: An Anomalous Predator-Prey Role Exchange between Cyprinids and Perch. PLoS One 2016; 11:e0156430. [PMID: 27276078 PMCID: PMC4898736 DOI: 10.1371/journal.pone.0156430] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Accepted: 05/15/2016] [Indexed: 11/18/2022] Open
Abstract
Piscivory in cyprinids (Cyprinidae) is extremely rare. Specifically, common bream (Abramis brama) and common carp (Cyprinus carpio) are zooplanktivorous fish in deep lentic waters. Nevertheless, we observed predation by these two cyprinids under natural conditions in the Vír Reservoir, Czech Republic. We conducted diet analysis for cyprinids caught by trawling and gillnets and the large amount of young-of-the-year (YOY) perch (Perca fluviatilis), with sizes of 37–52 mm standard length, were found in their digestive tracts. In 2010, a large amount of YOY perch caused a significant decrease in Daphnia spp. size and abundance in the reservoir. Hence, a food deficit was induced for the cyprinids, apparent also from the poor nutritional condition of common bream which was much worse than the condition of those in similar reservoirs. Common carp and common bream shifted to forced piscivory, and they utilized the YOY perch as an alternative food source. In contrast, smaller species, such as roach (Rutilus rutilus) and bleak (Alburnus alburnus), widely utilized planktonic cyanobacteria. In the following year, YOY perch occurred in significantly lower numbers and conversely, Daphnia spp. size and abundance were significantly higher. The forced piscivory was not observed. Our results indicate a switch to forced piscivory by cyprinids, which was caused by a shortage of their natural food source. Moreover, this phenomenon presents an effective mechanism for reduction in the numbers of YOY perch, ensuring the stability of the ecosystem.
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Affiliation(s)
- Lukáš Vejřík
- Biology Centre of the Czech Academy of Sciences, v.v.i., Institute of Hydrobiology, Na Sádkách 7, 37005, České Budějovice, Czech Republic
- Faculty of Science, University of South Bohemia in České Budějovice, Branišovská 31, 37005, České Budějovice, Czech Republic
- * E-mail:
| | - Ivana Matějíčková
- Biology Centre of the Czech Academy of Sciences, v.v.i., Institute of Hydrobiology, Na Sádkách 7, 37005, České Budějovice, Czech Republic
- Faculty of Science, University of South Bohemia in České Budějovice, Branišovská 31, 37005, České Budějovice, Czech Republic
| | - Jaromír Seďa
- Biology Centre of the Czech Academy of Sciences, v.v.i., Institute of Hydrobiology, Na Sádkách 7, 37005, České Budějovice, Czech Republic
| | - Petr Blabolil
- Biology Centre of the Czech Academy of Sciences, v.v.i., Institute of Hydrobiology, Na Sádkách 7, 37005, České Budějovice, Czech Republic
- Faculty of Science, University of South Bohemia in České Budějovice, Branišovská 31, 37005, České Budějovice, Czech Republic
| | - Tomáš Jůza
- Biology Centre of the Czech Academy of Sciences, v.v.i., Institute of Hydrobiology, Na Sádkách 7, 37005, České Budějovice, Czech Republic
| | - Mojmír Vašek
- Biology Centre of the Czech Academy of Sciences, v.v.i., Institute of Hydrobiology, Na Sádkách 7, 37005, České Budějovice, Czech Republic
| | - Daniel Ricard
- Biology Centre of the Czech Academy of Sciences, v.v.i., Institute of Hydrobiology, Na Sádkách 7, 37005, České Budějovice, Czech Republic
| | - Josef Matěna
- Biology Centre of the Czech Academy of Sciences, v.v.i., Institute of Hydrobiology, Na Sádkách 7, 37005, České Budějovice, Czech Republic
| | - Jaroslava Frouzová
- Biology Centre of the Czech Academy of Sciences, v.v.i., Institute of Hydrobiology, Na Sádkách 7, 37005, České Budějovice, Czech Republic
| | - Jan Kubečka
- Biology Centre of the Czech Academy of Sciences, v.v.i., Institute of Hydrobiology, Na Sádkách 7, 37005, České Budějovice, Czech Republic
| | - Milan Říha
- Biology Centre of the Czech Academy of Sciences, v.v.i., Institute of Hydrobiology, Na Sádkách 7, 37005, České Budějovice, Czech Republic
| | - Martin Čech
- Biology Centre of the Czech Academy of Sciences, v.v.i., Institute of Hydrobiology, Na Sádkách 7, 37005, České Budějovice, Czech Republic
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Šmejkal M, Ricard D, Prchalová M, Říha M, Muška M, Blabolil P, Čech M, Vašek M, Jůza T, Monteoliva Herreras A, Encina L, Peterka J, Kubečka J. Biomass and abundance biases in European standard gillnet sampling. PLoS One 2015; 10:e0122437. [PMID: 25793776 PMCID: PMC4368622 DOI: 10.1371/journal.pone.0122437] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2014] [Accepted: 02/14/2015] [Indexed: 11/19/2022] Open
Abstract
The European Standard EN 14757 recommends gillnet mesh sizes that range from 5 to 55mm (knot-to-knot) for the standard monitoring of fish assemblages and suggests adding gillnets with larger mesh sizes if necessary. Our research showed that the recommended range of mesh sizes did not provide a representative picture of fish sizes for larger species that commonly occur in continental Europe. We developed a novel, large mesh gillnet which consists of mesh sizes 70, 90, 110 and 135mm (knot to knot, 10m panels) and assessed its added value for monitoring purposes. From selectivity curves obtained by sampling with single mesh size gillnets (11 mesh sizes 6 - 55mm) and large mesh gillnets, we identified the threshold length of bream (Abramis brama) above which this widespread large species was underestimated by European standard gillnet catches. We tested the European Standard gillnet by comparing its size composition with that obtained during concurrent pelagic trawling and purse seining in a cyprinid-dominated reservoir and found that the European Standard underestimated fish larger than 292mm by 26 times. The inclusion of large mesh gillnets in the sampling design removed this underestimation. We analysed the length-age relationship of bream in the Římov Reservoir, and concluded that catches of bream larger than 292mm and older than five years were seriously underrepresented in European Standard gillnet catches. The Římov Reservoir is a typical cyprinid-dominated water body where the biomass of bream > 292mm formed 70% of the pelagic trawl and purse seine catch. The species-specific relationships between the large mesh gillnet catch and European Standard catch suggested that the presence of carp (Cyprinus carpio), European catfish (Silurus glanis), tench (Tinca tinca) or bream warrants the use of both gillnet types. We suggest extending the gillnet series in the European Standard to avoid misinterpretation of fish community biomass estimates.
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Affiliation(s)
- Marek Šmejkal
- Biology Centre of the Academy of Sciences of the Czech Republic, v.v.i., Institute of Hydrobiology, České Budějovice, Czech Republic
- Faculty of Science, University of South Bohemia, České Budějovice, Czech Republic
| | - Daniel Ricard
- Biology Centre of the Academy of Sciences of the Czech Republic, v.v.i., Institute of Hydrobiology, České Budějovice, Czech Republic
| | - Marie Prchalová
- Biology Centre of the Academy of Sciences of the Czech Republic, v.v.i., Institute of Hydrobiology, České Budějovice, Czech Republic
| | - Milan Říha
- Biology Centre of the Academy of Sciences of the Czech Republic, v.v.i., Institute of Hydrobiology, České Budějovice, Czech Republic
| | - Milan Muška
- Biology Centre of the Academy of Sciences of the Czech Republic, v.v.i., Institute of Hydrobiology, České Budějovice, Czech Republic
| | - Petr Blabolil
- Biology Centre of the Academy of Sciences of the Czech Republic, v.v.i., Institute of Hydrobiology, České Budějovice, Czech Republic
- Faculty of Science, University of South Bohemia, České Budějovice, Czech Republic
| | - Martin Čech
- Biology Centre of the Academy of Sciences of the Czech Republic, v.v.i., Institute of Hydrobiology, České Budějovice, Czech Republic
| | - Mojmír Vašek
- Biology Centre of the Academy of Sciences of the Czech Republic, v.v.i., Institute of Hydrobiology, České Budějovice, Czech Republic
| | - Tomáš Jůza
- Biology Centre of the Academy of Sciences of the Czech Republic, v.v.i., Institute of Hydrobiology, České Budějovice, Czech Republic
| | | | - Lourdes Encina
- Department of Plant Biology and Ecology, Faculty of Biology, University of Seville, Seville, Spain
| | - Jiří Peterka
- Biology Centre of the Academy of Sciences of the Czech Republic, v.v.i., Institute of Hydrobiology, České Budějovice, Czech Republic
| | - Jan Kubečka
- Biology Centre of the Academy of Sciences of the Czech Republic, v.v.i., Institute of Hydrobiology, České Budějovice, Czech Republic
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Jůza T, Mrkvička T, Blabolil P, Cech M, Peterka J, Vašek M, Kubečka J. Occurrence of age-0 year dwarf pikeperch Sander lucioperca in late summer--an overlooked phenomenon in reservoirs. J Fish Biol 2013; 83:1444-1452. [PMID: 24580676 DOI: 10.1111/jfb.12229] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2013] [Accepted: 08/13/2013] [Indexed: 06/03/2023]
Abstract
Late summer sampling of pelagic age-0 year fish communities in five Czech reservoirs and one Dutch reservoir revealed extremely small age-0 year pikeperch Sander lucioperca (mean 24 mm standard length, LS , minimum 13 mm LS ) alongside more normal-sized S. lucioperca that are found at the end of the first growing season (mean 50 mm LS ), resulting in two clearly size-separated cohorts. Reference to such small age-0 year S. lucioperca in lakes or reservoirs at this time of year and in such large numbers are almost absent the scientific literature, and the presence of these small S. lucioperca is contradictory to the common understanding of the reproductive biology of this species. This overlooked phenomenon may have a major effect on the population dynamics of this valuable species because of size-dependent winter mortality.
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Affiliation(s)
- T Jůza
- Biology Centre AS CR v.v.i., Institute of Hydrobiology, České Budějovice, Czech Republic
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