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To assess potential impacts of effluents from Key Lake and McClean Lake uranium operations on freshwater systems, morphometric (weight, length, condition factor) and biochemical (total body lipids and triglycerides, liver triglycerides, muscle protein, muscle RNA/DNA ratio) measures of growth and bioenergetics were determined in young-of-the-year (YOY) fishes collected in fall and spring. It was predicted that fishes exposed to mining and milling effluents would be in poorer condition relative to fishes from reference sites and that fishes would be depleted in lipids and triglycerides in the spring compared to the previous fall following a northern winter. Various total body lipid and triglyceride measurement methods were initially compared and validated. <p>Lakes receiving effluent at Key Lake (in operation > 20 years) were higher in metals, ions and ammonia compared to exposure sites at McClean Lake (in operation < 10 years). At Key Lake, there were site and season differences in total body lipids and triglycerides in YOY northern pike (<i>Esox lucius</i>) and burbot (Lota lota), with fishes being fattier at exposure sites compared to fishes at the reference site, and fish being fattier in spring relative to fall. A local prey item, spottail shiners (<i>Notropis hudsonius</i>), from an exposure lake were higher in triglycerides compared to shiners from a reference site, suggesting an indirect effect of uranium operation effluent on pike and burbot bioenergetics via food web enrichment. At McClean Lake, there were site and season increases in lipids and triglycerides in burbot from the exposure site, however there were no site differences in any morphometric or biochemical endpoint for northern pike. Slimy sculpin (<i>Cottus cognatus</i>) were the only species with lower triglyceride content in the spring following winter. <p>Overall, biochemical measures of growth (muscle protein, muscle RNA/DNA ratio) did not vary with effluent exposure at either uranium operation. Lipids and triglycerides were useful biochemical endpoints that frequently detected site and season differences in fish condition that were not noted with morphometric measures. Site and season differences in fish lipids and triglycerides at sites receiving mining and milling effluents revealed an impact of the uranium operations on indigenous YOY fish condition.

To assess potential impacts of effluents from Key Lake and McClean Lake uranium operations on freshwater systems, morphometric (weight, length, condition factor) and biochemical (total body lipids and triglycerides, liver triglycerides, muscle protein, muscle RNA/DNA ratio) measures of growth and bioenergetics were determined in young-of-the-year (YOY) fishes collected in fall and spring. It was predicted that fishes exposed to mining and milling effluents would be in poorer condition relative to fishes from reference sites and that fishes would be depleted in lipids and triglycerides in the spring compared to the previous fall following a northern winter. Various total body lipid and triglyceride measurement methods were initially compared and validated. <p>Lakes receiving effluent at Key Lake (in operation > 20 years) were higher in metals, ions and ammonia compared to exposure sites at McClean Lake (in operation < 10 years). At Key Lake, there were site and season differences in total body lipids and triglycerides in YOY northern pike (<i>Esox lucius</i>) and burbot (Lota lota), with fishes being fattier at exposure sites compared to fishes at the reference site, and fish being fattier in spring relative to fall. A local prey item, spottail shiners (<i>Notropis hudsonius</i>), from an exposure lake were higher in triglycerides compared to shiners from a reference site, suggesting an indirect effect of uranium operation effluent on pike and burbot bioenergetics via food web enrichment. At McClean Lake, there were site and season increases in lipids and triglycerides in burbot from the exposure site, however there were no site differences in any morphometric or biochemical endpoint for northern pike. Slimy sculpin (<i>Cottus cognatus</i>) were the only species with lower triglyceride content in the spring following winter. <p>Overall, biochemical measures of growth (muscle protein, muscle RNA/DNA ratio) did not vary with effluent exposure at either uranium operation. Lipids and triglycerides were useful biochemical endpoints that frequently detected site and season differences in fish condition that were not noted with morphometric measures. Site and season differences in fish lipids and triglycerides at sites receiving mining and milling effluents revealed an impact of the uranium operations on indigenous YOY fish condition.

Le puceron du soya (Aphis glycines) est le ravageur le plus important de la culture du soya en Amérique du Nord. Quoi qu’efficaces, les pesticides permettent le contrôle des ravageurs que pour une courte période et nécessitent plusieurs applications au cours de la saison. De plus, ils sont dommageables pour l’environnement et la santé humaine. La lutte biologique se présente comme une alternative crédible pour le contrôle des populations d’A. glycines en Amérique du Nord. Trois parasitoïdes (Binodoxys communis, Aphidius colemani, Aphelinus certus) du puceron semblent être des candidats prometteurs. L’objectif de cette étude était d’examiner certains attributs biologiques de ces parasitoïdes au Québec. Dans le cas de B. communis et A. certus nous avons estimé leur synchronisme saisonnier ainsi que leur résistance au froid en laboratoire et en conditions naturelles. Dans le cas, d’A. colemani, nous avons évalué sa capacité à parasiter le puceron du soya et à se disperser dans un champ de soya. Nos résultats démontrent que la souche utilisée de B. communis a perdu sa capacité à entrer en diapause, probablement à cause de la longue période d’élevage en laboratoire qui a suivi son échantillonnage en Asie. Aphelinus certus démontre un potentiel intéressant puisqu’il possède un synchronisme saisonnier tant en automne qu’au printemps avec son hôte ainsi qu’un bon potentiel de survie hivernale au Québec. Quant à A. colemani, les essais suggèrent qu’il se disperse rapidement hors des champs sans attaquer de manière significative A. glycines. / The soybean aphid (Aphis glycines) has become the most important pest of soybean in North America. Despite their efficiency, insecticides do eliminate the pest only for short periods and several applications may be required during the growing season. Furthermore, they are detrimental for the environment and human health. Biological control appears as a promising alternative for the control of A. glycines populations in North America. Three parasitoid species (Binodoxys communis, Aphidius colemani, Aphelinus certus) have been identified as potential candidates. The objective of this study was to study some biological attributes of these parasitoids in Québec. For B. communis and A. certus we examined their seasonal activities and their cold hardiness in laboratory and natural conditions. For A. colemani, we evaluated its capacity to parasite the soybean aphid and to disperse in soybean fields. Our results revealed that the B. communis strain we used had lost its capacity to enter diapause, probably due to the long period of laboratory rearing following its sampling in Asia. Aphelinus certus showed an interesting potential because the species is synchronized with its host both in the fall and the spring and has the capacity to overwinter in Québec. For A. colemani, the essays suggest that it disperses rapidly out of the field without attacking significantly A. glycines.

Le puceron du soya (Aphis glycines) est le ravageur le plus important de la culture du soya en Amérique du Nord. Quoi qu’efficaces, les pesticides permettent le contrôle des ravageurs que pour une courte période et nécessitent plusieurs applications au cours de la saison. De plus, ils sont dommageables pour l’environnement et la santé humaine. La lutte biologique se présente comme une alternative crédible pour le contrôle des populations d’A. glycines en Amérique du Nord. Trois parasitoïdes (Binodoxys communis, Aphidius colemani, Aphelinus certus) du puceron semblent être des candidats prometteurs. L’objectif de cette étude était d’examiner certains attributs biologiques de ces parasitoïdes au Québec. Dans le cas de B. communis et A. certus nous avons estimé leur synchronisme saisonnier ainsi que leur résistance au froid en laboratoire et en conditions naturelles. Dans le cas, d’A. colemani, nous avons évalué sa capacité à parasiter le puceron du soya et à se disperser dans un champ de soya. Nos résultats démontrent que la souche utilisée de B. communis a perdu sa capacité à entrer en diapause, probablement à cause de la longue période d’élevage en laboratoire qui a suivi son échantillonnage en Asie. Aphelinus certus démontre un potentiel intéressant puisqu’il possède un synchronisme saisonnier tant en automne qu’au printemps avec son hôte ainsi qu’un bon potentiel de survie hivernale au Québec. Quant à A. colemani, les essais suggèrent qu’il se disperse rapidement hors des champs sans attaquer de manière significative A. glycines. / The soybean aphid (Aphis glycines) has become the most important pest of soybean in North America. Despite their efficiency, insecticides do eliminate the pest only for short periods and several applications may be required during the growing season. Furthermore, they are detrimental for the environment and human health. Biological control appears as a promising alternative for the control of A. glycines populations in North America. Three parasitoid species (Binodoxys communis, Aphidius colemani, Aphelinus certus) have been identified as potential candidates. The objective of this study was to study some biological attributes of these parasitoids in Québec. For B. communis and A. certus we examined their seasonal activities and their cold hardiness in laboratory and natural conditions. For A. colemani, we evaluated its capacity to parasite the soybean aphid and to disperse in soybean fields. Our results revealed that the B. communis strain we used had lost its capacity to enter diapause, probably due to the long period of laboratory rearing following its sampling in Asia. Aphelinus certus showed an interesting potential because the species is synchronized with its host both in the fall and the spring and has the capacity to overwinter in Québec. For A. colemani, the essays suggest that it disperses rapidly out of the field without attacking significantly A. glycines.