The predatory behavior of invasive species can affect their ecological impact, and offer opportunities for targeted control. In Australia, tadpoles of invasive cane toads （Rhinella marina） do not consume eggs of nat...The predatory behavior of invasive species can affect their ecological impact, and offer opportunities for targeted control. In Australia, tadpoles of invasive cane toads （Rhinella marina） do not consume eggs of native anurans, but are strongly attracted to （and consume） newly-laid eggs of conspecifics; chemical cues from such eggs （or adult secretions） thus can be used to attract toad tadpoles to traps. Do other invasive anurans show similar selectivity？ Our laboratory trials on a Chinese population of invasive American bullfrogs （Lithobates catesbeianus） revealed similar behaviors as exhibited by Australian cane toads. Bullfrog tadpoles rarely consumed the eggs of native anurarts, but were attracted to both bullfrog eggs and bullfrog skin secretions. Although the attraction response was less intense in bullfrogs than in cane toads, it might nonetheless enable selective removal of bullfrog tadpoles from invaded sites.展开更多
The aim of this study was to install and assess the efficiency of a constructed wetland for wastewater treatment from bullfrog farming (Lithobates catesbeianus) at fattening growth phase. Water detention time was not ...The aim of this study was to install and assess the efficiency of a constructed wetland for wastewater treatment from bullfrog farming (Lithobates catesbeianus) at fattening growth phase. Water detention time was not controlled since wastewater input flow varied according to the biomass of animals maintained in stalls. The study was divided into two phases, with higher and lower bullfrog biomass respectively for phase I and II. A higher removal of nitrite, biochemical oxygen demand, and thermotolerant coliforms was observed at phase I whereas a higher removal of turbidity, nitrate, total phosphorus, total suspended solids, total dissolved solids, and chlorophyll a occurred at phase II. Wastewater treatments using constructed wetland systems with high organic load require a higher water detention time for a better load removal. The treatment effect was positive since this wastewater flowed directly into fishponds or streams, which might promote eutrophication. Thus, wastewater treatment is essential to minimize the impact caused by frog farming on receiving water bodies, promoting the sustainability of this activity in Brazil.展开更多
Wetlands are often created through wetland mitigation to replace lost natural wetlands, but further evaluation is needed to determine the ability of a created wetland to replace lost wetland functions, especially prov...Wetlands are often created through wetland mitigation to replace lost natural wetlands, but further evaluation is needed to determine the ability of a created wetland to replace lost wetland functions, especially providing wildlife habitat. We used a mesocosm design to compare the water quality between three created wetlands and three natural wetlands in West Virginia, USA and to evaluate how the water quality from the two wetland types were able to support metamorphosis in larval spring peepers (Pseudacris crucifer) and wood frogs (Lithobates sylvaticus) across two years (2014-2015). Responses in metamorphosis rates differed between species and between years. Spring peepers displayed similar metamorphosis rates in the created and natural wetlands in both years of the study. Wood frogs displayed similar metamorphosis rates in created and natural wetlands in 2015, but in 2014 wood frogs reached metamorphosis in less time and at a larger body size in the natural wetlands, suggesting that the wood frogs that developed in the natural wetlands may have higher fitness than those that developed in the created wetlands. Water quality was largely similar between created and natural wetlands, although dissolved oxygen, conductivity, and pH varied between mesocosms and wetlands. Our study suggests that created wetlands may be providing partial mitigation in terms of water quality for amphibian development. We recommend that future monitoring of created wetlands include measures of juvenile amphibian recruitment as well as additional habitat variables to better determine the ability of created wetlands to function as amphibian habitat.展开更多
基金supported by grants from the National Natural Science Foundation of China(31370545)National Science Foundation of China (31572284)
文摘The predatory behavior of invasive species can affect their ecological impact, and offer opportunities for targeted control. In Australia, tadpoles of invasive cane toads （Rhinella marina） do not consume eggs of native anurans, but are strongly attracted to （and consume） newly-laid eggs of conspecifics; chemical cues from such eggs （or adult secretions） thus can be used to attract toad tadpoles to traps. Do other invasive anurans show similar selectivity？ Our laboratory trials on a Chinese population of invasive American bullfrogs （Lithobates catesbeianus） revealed similar behaviors as exhibited by Australian cane toads. Bullfrog tadpoles rarely consumed the eggs of native anurarts, but were attracted to both bullfrog eggs and bullfrog skin secretions. Although the attraction response was less intense in bullfrogs than in cane toads, it might nonetheless enable selective removal of bullfrog tadpoles from invaded sites.
文摘The aim of this study was to install and assess the efficiency of a constructed wetland for wastewater treatment from bullfrog farming (Lithobates catesbeianus) at fattening growth phase. Water detention time was not controlled since wastewater input flow varied according to the biomass of animals maintained in stalls. The study was divided into two phases, with higher and lower bullfrog biomass respectively for phase I and II. A higher removal of nitrite, biochemical oxygen demand, and thermotolerant coliforms was observed at phase I whereas a higher removal of turbidity, nitrate, total phosphorus, total suspended solids, total dissolved solids, and chlorophyll a occurred at phase II. Wastewater treatments using constructed wetland systems with high organic load require a higher water detention time for a better load removal. The treatment effect was positive since this wastewater flowed directly into fishponds or streams, which might promote eutrophication. Thus, wastewater treatment is essential to minimize the impact caused by frog farming on receiving water bodies, promoting the sustainability of this activity in Brazil.
文摘Wetlands are often created through wetland mitigation to replace lost natural wetlands, but further evaluation is needed to determine the ability of a created wetland to replace lost wetland functions, especially providing wildlife habitat. We used a mesocosm design to compare the water quality between three created wetlands and three natural wetlands in West Virginia, USA and to evaluate how the water quality from the two wetland types were able to support metamorphosis in larval spring peepers (Pseudacris crucifer) and wood frogs (Lithobates sylvaticus) across two years (2014-2015). Responses in metamorphosis rates differed between species and between years. Spring peepers displayed similar metamorphosis rates in the created and natural wetlands in both years of the study. Wood frogs displayed similar metamorphosis rates in created and natural wetlands in 2015, but in 2014 wood frogs reached metamorphosis in less time and at a larger body size in the natural wetlands, suggesting that the wood frogs that developed in the natural wetlands may have higher fitness than those that developed in the created wetlands. Water quality was largely similar between created and natural wetlands, although dissolved oxygen, conductivity, and pH varied between mesocosms and wetlands. Our study suggests that created wetlands may be providing partial mitigation in terms of water quality for amphibian development. We recommend that future monitoring of created wetlands include measures of juvenile amphibian recruitment as well as additional habitat variables to better determine the ability of created wetlands to function as amphibian habitat.
