The Experts below are selected from a list of 231 Experts worldwide ranked by ideXlab platform
Robby Stoks - One of the best experts on this subject based on the ideXlab platform.
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Is salinity tolerance the key to success for the invasive water bug Trichocorixa verticalis?
2016Co-Authors: F. Van, Hendrik Trekels, Andy J. Green, De Meutter, Robby StoksAbstract:North Amer-ican water bug (Heteroptera: Corixidae) that occurs in brackish and saline aquatic systems. Recently, it has been found invading three continents including Europe. Its invasive success has been attributed to the capacity of tolerating hypersalinity. We compared both the realized and standardized salinity niche of invasive T. verticalis and native Corixidae to verify if T. verticalis may fill in an unoccupied niche. We first established the field distribution of T. verticalis and native Corixidae along a salinity gradient. Second, we experimentally tested the salinity tolerance of T. verticalis and three common native Corixidae spe-cies. Of the seven Corixidae species found in the field study, three were positively related to the salinity gradient: S. selecta, S. stagnalis, and T. verticalis. T. verticalis showed the highest salinity optimum, however, after correcting for environmental back-ground variation, salinity optima differed little among the three halophilic species. In the salinity tolerance experiment, S. selecta outperformed T. verticalis, which performed as well as S. stagnalis. Based on our experimental results, we cannot support the hypoth-esis that T. verticalis ’ invasion is mediated by a high salinity tolerance that allows this species to colonize habitats unoccupied by native Corixidae. Although these findings contrast with the field patterns in which T. verticalis showed the highest niche optimum and tolerance, these patterns may have been partly due to other environmental factors, particularly anthropo-genic disturbance. Our comparative results are for adults only, and it remains possible that relative salinity tolerance patterns for juveniles differ from that for adults, which may add to the observed field pattern
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Predator cues magnify effects of the pesticide endosulfan in water bugs in a multi-species test in outdoor containers.
Aquatic toxicology (Amsterdam Netherlands), 2013Co-Authors: Hendrik Trekels, Frank Van De Meutter, Robby StoksAbstract:Pesticides have become major stressors in many aquatic communities. Laboratory studies suggest their impact may be further magnified in the presence of cues from predators. Despite their importance for ecological risk assessment, synergisms between pesticides and predator cues have not been confirmed under semi-natural outdoor conditions. We evaluated how the presence of predator cues and the presence of a non-corixid community affect the pesticide sensitivity of five water bug (Corixidae) species in an outdoor, multi-species container experiment. The experiment employed a full factorial design with two pesticide treatments, two predator cue treatments and two (non-corixid) community treatments (absence versus presence of Cloeon dipterum mayfly larvae, Ischnura elegans damselfly larvae and Physa acuta snails). The pesticide treatment negatively affected survival in Cymatia coleoptrata, and to a lesser extent, Sigara lateralis, but not in the other three Corixidae species (Hesperocorixa linnaei, Sigara iactans and Sigara striata). The addition of pesticides did not significantly affect body mass in the latter four species, unless combined with predator cues. To our knowledge this is the first report of this synergism under semi-natural, outdoor conditions. Neither lethal nor sublethal pesticide effects in the Corixidae depended on the community context, yet the presence of the non-corixid community when combined with predator cues reduced survival and body mass. Our results suggest that the here documented synergism between pesticides and predator cues may occur in nature.
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Is salinity tolerance the key to success for the invasive water bug Trichocorixa verticalis
Hydrobiologia, 2010Co-Authors: F. Van De Meutter, Hendrik Trekels, Andy J. Green, Robby StoksAbstract:Trichocorixa verticalis is a North American water bug (Heteroptera: Corixidae) that occurs in brackish and saline aquatic systems. Recently, it has been found invading three continents including Europe. Its invasive success has been attributed to the capacity of tolerating hypersalinity. We compared both the realized and standardized salinity niche of invasive T. verticalis and native Corixidae to verify if T. verticalis may fill in an unoccupied niche. We first established the field distribution of T. verticalis and native Corixidae along a salinity gradient. Second, we experimentally tested the salinity tolerance of T. verticalis and three common native Corixidae species. Of the seven Corixidae species found in the field study, three were positively related to the salinity gradient: S. selecta, S. stagnalis, and T. verticalis. T. verticalis showed the highest salinity optimum, however, after correcting for environmental background variation, salinity optima differed little among the three halophilic species. In the salinity tolerance experiment, S. selecta outperformed T. verticalis, which performed as well as S. stagnalis. Based on our experimental results, we cannot support the hypothesis that T. verticalis’ invasion is mediated by a high salinity tolerance that allows this species to colonize habitats unoccupied by native Corixidae. Although these findings contrast with the field patterns in which T. verticalis showed the highest niche optimum and tolerance, these patterns may have been partly due to other environmental factors, particularly anthropogenic disturbance. Our comparative results are for adults only, and it remains possible that relative salinity tolerance patterns for juveniles differ from that for adults, which may add to the observed field pattern.
Andy J. Green - One of the best experts on this subject based on the ideXlab platform.
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Is salinity tolerance the key to success for the invasive water bug Trichocorixa verticalis?
2016Co-Authors: F. Van, Hendrik Trekels, Andy J. Green, De Meutter, Robby StoksAbstract:North Amer-ican water bug (Heteroptera: Corixidae) that occurs in brackish and saline aquatic systems. Recently, it has been found invading three continents including Europe. Its invasive success has been attributed to the capacity of tolerating hypersalinity. We compared both the realized and standardized salinity niche of invasive T. verticalis and native Corixidae to verify if T. verticalis may fill in an unoccupied niche. We first established the field distribution of T. verticalis and native Corixidae along a salinity gradient. Second, we experimentally tested the salinity tolerance of T. verticalis and three common native Corixidae spe-cies. Of the seven Corixidae species found in the field study, three were positively related to the salinity gradient: S. selecta, S. stagnalis, and T. verticalis. T. verticalis showed the highest salinity optimum, however, after correcting for environmental back-ground variation, salinity optima differed little among the three halophilic species. In the salinity tolerance experiment, S. selecta outperformed T. verticalis, which performed as well as S. stagnalis. Based on our experimental results, we cannot support the hypoth-esis that T. verticalis ’ invasion is mediated by a high salinity tolerance that allows this species to colonize habitats unoccupied by native Corixidae. Although these findings contrast with the field patterns in which T. verticalis showed the highest niche optimum and tolerance, these patterns may have been partly due to other environmental factors, particularly anthropo-genic disturbance. Our comparative results are for adults only, and it remains possible that relative salinity tolerance patterns for juveniles differ from that for adults, which may add to the observed field pattern
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The impact of the North American waterbug Trichocorixa verticalis (Fieber) on aquatic macroinvertebrate communities in southern Europe.
Fundamental and Applied Limnology, 2010Co-Authors: Frank Van De Meutter, Hendrik Trekels, Andy J. GreenAbstract:The North American waterbug Trichocorixa verticalis (Heteroptera: Corixidae) has recently invaded brackish water systems on three continents. Despite its potential to be a keystone species in hypersaline waters in its home range, its effect on the communities it invades is yet unstudied. By doing a field survey in 29 ponds in Donana, southern Europe some years after T. verticalis was first recorded there, we aimed to establish its prevalence and impact on the local invertebrate community, especially the local corixid community with which it is likely to compete. T. verticalis showed the highest prevalence among all seven Corixidae species found. It occasionally reached high local abundance, especially at high salinity. T. verticalis also appeared to be better than native Corixidae at coping with human disturbance. We could not identify significant effects of T. verticalis on the local corixid community nor on the invertebrate community at large. Further experimental research will be needed to confirm these results. Special attention should be paid to hypersaline systems where T. verticalis may act as a top predator.
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Is salinity tolerance the key to success for the invasive water bug Trichocorixa verticalis
Hydrobiologia, 2010Co-Authors: F. Van De Meutter, Hendrik Trekels, Andy J. Green, Robby StoksAbstract:Trichocorixa verticalis is a North American water bug (Heteroptera: Corixidae) that occurs in brackish and saline aquatic systems. Recently, it has been found invading three continents including Europe. Its invasive success has been attributed to the capacity of tolerating hypersalinity. We compared both the realized and standardized salinity niche of invasive T. verticalis and native Corixidae to verify if T. verticalis may fill in an unoccupied niche. We first established the field distribution of T. verticalis and native Corixidae along a salinity gradient. Second, we experimentally tested the salinity tolerance of T. verticalis and three common native Corixidae species. Of the seven Corixidae species found in the field study, three were positively related to the salinity gradient: S. selecta, S. stagnalis, and T. verticalis. T. verticalis showed the highest salinity optimum, however, after correcting for environmental background variation, salinity optima differed little among the three halophilic species. In the salinity tolerance experiment, S. selecta outperformed T. verticalis, which performed as well as S. stagnalis. Based on our experimental results, we cannot support the hypothesis that T. verticalis’ invasion is mediated by a high salinity tolerance that allows this species to colonize habitats unoccupied by native Corixidae. Although these findings contrast with the field patterns in which T. verticalis showed the highest niche optimum and tolerance, these patterns may have been partly due to other environmental factors, particularly anthropogenic disturbance. Our comparative results are for adults only, and it remains possible that relative salinity tolerance patterns for juveniles differ from that for adults, which may add to the observed field pattern.
António J.a. Nogueira - One of the best experts on this subject based on the ideXlab platform.
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Sensitivity of macroinvertebrates to carbendazim under semi-field conditions in Thailand: implications for the use of temperate toxicity data in a tropical risk assessment of fungicides.
Chemosphere, 2008Co-Authors: Michiel A. Daam, Kriengkrai Satapornvanit, Paul J. Van Den Brink, António J.a. NogueiraAbstract:Abstract The present paper discusses the fate of the fungicide carbendazim (nominal concentrations: 0, 3.3, 33, 100 and 1000 μg L −1 ) and its effects on the macroinvertebrate community in outdoor microcosms set up in Thailand. Fate and threshold values were subsequently compared with those noted in temperate model ecosystem studies in order to evaluate to which extent toxicity data generated in temperate regions for compounds like carbendazim may be extrapolated to tropical areas. Carbendazim disappeared faster from the water column than reported in temperate model ecosystem studies, which is explained by a possibly greater microbial breakdown of the fungicide under the tropical conditions tested. The No Observed Effect Concentration (NOEC) calculated in the present study for the macroinvertebrate community was the same as recorded in a study carried out in The Netherlands (3.3 μg L −1 ). However, most sensitive representatives in the latter study were “worm-like” taxa, whereas water boatmen (Corixidae) were the most sensitive macroinvertebrates in the present study. The ecological realism of a tropical risk assessment based on temperate organisms that are less sensitive than local macroinvertebrates may be questionable. Recommendations for future research include testing the possibility to rear sensitive representatives of indigenous Thai Corixidae in the laboratory and conducting model ecosystem studies evaluating a wider range of pesticides on a larger tropical geographical scale.
Hendrik Trekels - One of the best experts on this subject based on the ideXlab platform.
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Is salinity tolerance the key to success for the invasive water bug Trichocorixa verticalis?
2016Co-Authors: F. Van, Hendrik Trekels, Andy J. Green, De Meutter, Robby StoksAbstract:North Amer-ican water bug (Heteroptera: Corixidae) that occurs in brackish and saline aquatic systems. Recently, it has been found invading three continents including Europe. Its invasive success has been attributed to the capacity of tolerating hypersalinity. We compared both the realized and standardized salinity niche of invasive T. verticalis and native Corixidae to verify if T. verticalis may fill in an unoccupied niche. We first established the field distribution of T. verticalis and native Corixidae along a salinity gradient. Second, we experimentally tested the salinity tolerance of T. verticalis and three common native Corixidae spe-cies. Of the seven Corixidae species found in the field study, three were positively related to the salinity gradient: S. selecta, S. stagnalis, and T. verticalis. T. verticalis showed the highest salinity optimum, however, after correcting for environmental back-ground variation, salinity optima differed little among the three halophilic species. In the salinity tolerance experiment, S. selecta outperformed T. verticalis, which performed as well as S. stagnalis. Based on our experimental results, we cannot support the hypoth-esis that T. verticalis ’ invasion is mediated by a high salinity tolerance that allows this species to colonize habitats unoccupied by native Corixidae. Although these findings contrast with the field patterns in which T. verticalis showed the highest niche optimum and tolerance, these patterns may have been partly due to other environmental factors, particularly anthropo-genic disturbance. Our comparative results are for adults only, and it remains possible that relative salinity tolerance patterns for juveniles differ from that for adults, which may add to the observed field pattern
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Predator cues magnify effects of the pesticide endosulfan in water bugs in a multi-species test in outdoor containers.
Aquatic toxicology (Amsterdam Netherlands), 2013Co-Authors: Hendrik Trekels, Frank Van De Meutter, Robby StoksAbstract:Pesticides have become major stressors in many aquatic communities. Laboratory studies suggest their impact may be further magnified in the presence of cues from predators. Despite their importance for ecological risk assessment, synergisms between pesticides and predator cues have not been confirmed under semi-natural outdoor conditions. We evaluated how the presence of predator cues and the presence of a non-corixid community affect the pesticide sensitivity of five water bug (Corixidae) species in an outdoor, multi-species container experiment. The experiment employed a full factorial design with two pesticide treatments, two predator cue treatments and two (non-corixid) community treatments (absence versus presence of Cloeon dipterum mayfly larvae, Ischnura elegans damselfly larvae and Physa acuta snails). The pesticide treatment negatively affected survival in Cymatia coleoptrata, and to a lesser extent, Sigara lateralis, but not in the other three Corixidae species (Hesperocorixa linnaei, Sigara iactans and Sigara striata). The addition of pesticides did not significantly affect body mass in the latter four species, unless combined with predator cues. To our knowledge this is the first report of this synergism under semi-natural, outdoor conditions. Neither lethal nor sublethal pesticide effects in the Corixidae depended on the community context, yet the presence of the non-corixid community when combined with predator cues reduced survival and body mass. Our results suggest that the here documented synergism between pesticides and predator cues may occur in nature.
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The impact of the North American waterbug Trichocorixa verticalis (Fieber) on aquatic macroinvertebrate communities in southern Europe.
Fundamental and Applied Limnology, 2010Co-Authors: Frank Van De Meutter, Hendrik Trekels, Andy J. GreenAbstract:The North American waterbug Trichocorixa verticalis (Heteroptera: Corixidae) has recently invaded brackish water systems on three continents. Despite its potential to be a keystone species in hypersaline waters in its home range, its effect on the communities it invades is yet unstudied. By doing a field survey in 29 ponds in Donana, southern Europe some years after T. verticalis was first recorded there, we aimed to establish its prevalence and impact on the local invertebrate community, especially the local corixid community with which it is likely to compete. T. verticalis showed the highest prevalence among all seven Corixidae species found. It occasionally reached high local abundance, especially at high salinity. T. verticalis also appeared to be better than native Corixidae at coping with human disturbance. We could not identify significant effects of T. verticalis on the local corixid community nor on the invertebrate community at large. Further experimental research will be needed to confirm these results. Special attention should be paid to hypersaline systems where T. verticalis may act as a top predator.
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Is salinity tolerance the key to success for the invasive water bug Trichocorixa verticalis
Hydrobiologia, 2010Co-Authors: F. Van De Meutter, Hendrik Trekels, Andy J. Green, Robby StoksAbstract:Trichocorixa verticalis is a North American water bug (Heteroptera: Corixidae) that occurs in brackish and saline aquatic systems. Recently, it has been found invading three continents including Europe. Its invasive success has been attributed to the capacity of tolerating hypersalinity. We compared both the realized and standardized salinity niche of invasive T. verticalis and native Corixidae to verify if T. verticalis may fill in an unoccupied niche. We first established the field distribution of T. verticalis and native Corixidae along a salinity gradient. Second, we experimentally tested the salinity tolerance of T. verticalis and three common native Corixidae species. Of the seven Corixidae species found in the field study, three were positively related to the salinity gradient: S. selecta, S. stagnalis, and T. verticalis. T. verticalis showed the highest salinity optimum, however, after correcting for environmental background variation, salinity optima differed little among the three halophilic species. In the salinity tolerance experiment, S. selecta outperformed T. verticalis, which performed as well as S. stagnalis. Based on our experimental results, we cannot support the hypothesis that T. verticalis’ invasion is mediated by a high salinity tolerance that allows this species to colonize habitats unoccupied by native Corixidae. Although these findings contrast with the field patterns in which T. verticalis showed the highest niche optimum and tolerance, these patterns may have been partly due to other environmental factors, particularly anthropogenic disturbance. Our comparative results are for adults only, and it remains possible that relative salinity tolerance patterns for juveniles differ from that for adults, which may add to the observed field pattern.
Esat Tarık Topkara - One of the best experts on this subject based on the ideXlab platform.
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Contribution to the knowledge on distribution of water boatmen (Heteroptera: Corixidae) in Turkey.
Ege Journal of Fisheries and Aquatic Sciences, 2013Co-Authors: Esat Tarık TopkaraAbstract:Turkiye’nin batisindaki 35 farkli lokaliteden toplanan Corixidae ornekleri sistematik acidan degerlendirilmistir. Calisma sonucunda, uc altfamilyaya (Micronectinae, Cymatiainae, Corixinae) ait 11 tur ve 2 altture dahil toplam 3222 birey incelenmistir. Yedi tur ve iki alttur arastirma bolgesindeki bazi lokaliteler icin ilk kez tespit edilmistir
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Contribution to the knowledge on distribution of water boatmen (Heteroptera: Corixidae) in Turkey Türkiye Corixidae (Heteroptera: Corixidae) dağilim bilgilerine katkilar
2013Co-Authors: Esat Tarık TopkaraAbstract:In this study, Corixidae samples were collected from 35 different aquatic localities in Western Turkey and evaluated systematically. As a result of the study, 3222 individuals were found, and 11 species and 2 subspecies belong to 3 subfamilies (Micronectinae, Cymatiainae, Corixinae) were identified in the laboratory. 7 species and 2 subspecies have been reported for the first time for some of the localities in the study area.