Publications by authors named "Bjarne Kvaestad"

Article Synopsis
  • Understanding the vertical migration pattern of sea lice copepodites is crucial for preventing infestations in farmed Atlantic salmon, but gathering this data can be difficult without disrupting natural behaviors.
  • A mesocosm platform was developed to collect data via a sensor package in an underwater housing that scans a transparent tube filled with copepodites, capturing various data over four days.
  • The platform uses a convolutional neural network for automatic counting of copepodites, revealing a diurnal migration pattern and demonstrating its capability to monitor aquatic species' densities at various depths autonomously.
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Gadolinium (Gd) is one of the rare earth elements (REY) and is widely used in magnetic resonance imaging (MRI) contrast agents. Anthropogenic Gd enrichment has frequently been found in wastewater treatment plant effluents in industrialised countries, rising concerns regarding effects on aquatic biota. This study investigates the acute toxicity and sublethal effects of Gd in two forms, as inorganic salt (GdCl) and as Gd-based contrast agent (GBCA), on early life stages of zebrafish (Danio rerio).

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Fish embryos can bioaccumulate and are particularly sensitive to a wide range of contaminants, which makes them suitable sentinels for environmental biomonitoring. However, fish embryos are very rarely utilized in environmental monitoring surveys, possibly due to their fragility and seasonality. In the present work, we assessed the applicability of caged lumpfish (Cyclopterus lumpus) eggs for in situ biomonitoring of exposure and effects of organic contaminants focusing on polyaromatic hydrocarbons and phenolic compounds.

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Microscopic imaging and morphometric measurement of fish embryos and larvae is essential in environmental monitoring of fish populations and to evaluate larvae development in aquaculture. Traditional microscopy methods require time-consuming, repetitive work by human experts. We present a method for fast imaging and analysis of millimetre-scale ichthyoplankton suspended in seawater.

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In this study we investigated potential impacts of Cu exposure at low, environmentally relevant, concentrations on early live stages of Atlantic cod (). Cod embryos and larvae were exposed to 0.5 μg/L (low), 2 μg/L (medium), and 6 μg/L (high) Cu from 4 to 17 days post fertilisation (dpf).

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Measurements of morphometrical parameters on i.e., fish larvae are useful for assessing the quality and condition of the specimen in environmental research or optimal growth in the cultivation industry.

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3,4-dichloroaniline (3,4-DCA) is one of the most widely produced anilines world-wide, used in plastic packaging, fabrics, pharmaceuticals, pesticides, dyes and paints as well as being a degradation product of several pesticides. 3,4-DCA has been detected in freshwater, brackish and marine environments. Although freshwater toxicity thresholds exist, very little toxicological information is available on marine and cold-water species.

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Marine tailing disposal (MTD) is sometimes practiced as an alternative to traditional mine tailing deposition on land. Environmental challenges connected to MTD include spreading of fine particulate matter in the water column and the potential release of metals and processing chemicals. This study investigated if tailing exposure affects the marine copepod Calanus finmarchicus, and whether effects are related to exposure to mineral particles or the presence of metals and/or processing chemicals in the tailings.

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Due to the heavy fuel oil (HFO) ban in Arctic maritime transport and new legislations restricting the sulphur content of fuel oils, new fuel oil types are continuously developed. However, the potential impacts of these new fuel oil types on marine ecosystems during accidental spills are largely unknown. In this study, we studied the toxicity of three marine fuel oils (two marine gas oils with low sulphur contents and a heavy fuel oil) in early life stages of cod (Gadus morhua).

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To achieve efficient and preventive measures against salmon lice ( Krøyer, 1838) infestation, a better understanding of behavioral patterns of the planktonic life stages is key. To investigate light responses in copepodites, a non-intrusive experimental system was designed to measure behavioral responses in a 12.5-l volume using machine vision technology and methodology.

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