Effects of crude oil water soluble fraction to capellin early life stages
Interest in oil and gas development in the Arctic shelf seas increases the risk of accidental spills. There are important gaps of knowledge related to the sensitivity of Arctic species and especially their early life stages (ELS). ELS of beach spawning capelin, a key pelagic fish species in the Barents Sea, are most prone to exposure to toxic oil compounds from accidental oil spill in coastal areas. The present study aims at examining the sub-lethal effects of embryonic exposure to low levels of crude oil WSF on exogenously feeding capelin larvae. the research team has long experience in conducting such studies (Frantzen et al. 2012, Nahrgang et al. 2012).
In April 2019, fertilised capelin eggs will be collected on the shores of Balsfjord and distributed to 21 incubators. Embryos will be exposed through an oiled rock column system, designed to deliver low and exponentially decreasing levels of crude oil WSF to the incubators over time (see Frantzen et al. 2012, Nahrgang et al. 2016 for the set-up). The oil exposure will consist in 4 increasing concentrations of oil (very low, low, middle and high) in addition to a control treatment (clean seawater). Each treatment will be replicated 4 times (5 treatments x 4 replicates= 20 incubators). One extra control incubators will provide additional embryos to follow the development without perturbing the main experimental units. The highest initial concentration of hydrocarbons will be in the upper ng/L range and represent already very low and environmentally relevant concentrations post oil spill. Exposure will be stopped at the onset of hatching when hatched larvae will be transferred to 25L conical incubators and receive uncontaminated water. Each of the 21 incubator will be containing ca 8000 embryos. The number is based on
previous experience linked to natural mortality and extensive sub-sampling. The experiment will be carried out until approx. 10 weeks after hatching. This will coincide with the last samples taken that may lead to mild discomfort to the individuals. Few samples will be taken at the embryo stage (development, bioaccumulation of contaminants), after hatching on yolk-sac larvae and on exogenously feeding larvae (growth, development, behavioural tests and cardiac activity). A detailed overview of the endpoints analysed during the course of the experiment is provided in Table 1 of the attachment.
Overall, the experiment is expected to give moderate discomfort. Previous studies have shown that oil will lead to deformities leading to reduced growth, feeding success and death (Frantzen et al 2012, Nahrgang et al. 2016). The
The knowledge gained in this study will firstly aide our understanding of the potential consequences of an oil spill on a key arctic species. Secondly, the data will be used to develop population models that can be coupled to ecological risk-based modelling frameworks. Such a framework is of great interest for stakeholders, such as the industry and environmental managers, in order to predict the potential effects of oil spill on key species and ecosystems.
In April 2019, fertilised capelin eggs will be collected on the shores of Balsfjord and distributed to 21 incubators. Embryos will be exposed through an oiled rock column system, designed to deliver low and exponentially decreasing levels of crude oil WSF to the incubators over time (see Frantzen et al. 2012, Nahrgang et al. 2016 for the set-up). The oil exposure will consist in 4 increasing concentrations of oil (very low, low, middle and high) in addition to a control treatment (clean seawater). Each treatment will be replicated 4 times (5 treatments x 4 replicates= 20 incubators). One extra control incubators will provide additional embryos to follow the development without perturbing the main experimental units. The highest initial concentration of hydrocarbons will be in the upper ng/L range and represent already very low and environmentally relevant concentrations post oil spill. Exposure will be stopped at the onset of hatching when hatched larvae will be transferred to 25L conical incubators and receive uncontaminated water. Each of the 21 incubator will be containing ca 8000 embryos. The number is based on
previous experience linked to natural mortality and extensive sub-sampling. The experiment will be carried out until approx. 10 weeks after hatching. This will coincide with the last samples taken that may lead to mild discomfort to the individuals. Few samples will be taken at the embryo stage (development, bioaccumulation of contaminants), after hatching on yolk-sac larvae and on exogenously feeding larvae (growth, development, behavioural tests and cardiac activity). A detailed overview of the endpoints analysed during the course of the experiment is provided in Table 1 of the attachment.
Overall, the experiment is expected to give moderate discomfort. Previous studies have shown that oil will lead to deformities leading to reduced growth, feeding success and death (Frantzen et al 2012, Nahrgang et al. 2016). The
The knowledge gained in this study will firstly aide our understanding of the potential consequences of an oil spill on a key arctic species. Secondly, the data will be used to develop population models that can be coupled to ecological risk-based modelling frameworks. Such a framework is of great interest for stakeholders, such as the industry and environmental managers, in order to predict the potential effects of oil spill on key species and ecosystems.