The impact of parasitic sea lice on harvest quantities and sizes of farmed salmon

Sea lice infections are recognized as a primary challenge for both salmon farming and adjacent stocks of wild salmon and sea trout, triggering strict regulations at farm sites and in larger coastal production areas. In 2017 the Norwegian government implemented the Traffic Light System (TLS), where green, yellow, and red lights imply that salmon farmers can raise, maintain, or must reduce production quantities depending on estimated sea lice-induced mortality of wild salmonids. Past research has explored the impacts of sea lice on the growth rate of salmon, indicating a possible link between sea lice numbers and harvest practices. This study evaluates the impact of sea lice on salmon farmers' harvest behavior focusing on production quantities and fish sizes while controlling for market prices of salmon and fish meal. We also investigate whether and to what extent the TLS implementation affects harvest behavior. Our empirical results indicate that farmers tend to harvest marginally faster in response to increasing levels of sea lice and slower during delousing operations. The implementation of the TLS strengthened the negative impacts of delousing operations on harvest quantities. Fish sizes at harvest are negatively associated with sea lice levels and delousing operations, regardless of the implementation of the TLS. Control variables, such as seawater temperature, salmon prices, and fish meal prices, also influence harvest quantities and fish sizes.publishedVersio

Competition in a fish auction: The case of Atlantic cod in Northern Norway

This study investigates the role of bidder numbers in fish auctions, a neglected area of past research and one that is of key importance for optimal use of limited marine resources. The study of a Norwegian auction for Atlantic cod shows that prices increase when two or more bidders participate in the auction. Holding other variables such as lot size, quality grade, and seasonality constant, price increases of 4.51 %, 6.47 %, 7.18 %, and 9.88 % in auctions with two, three, four, and five plus bidders were found, compared to auctions with only one bidder. The increasing prices following from higher bidder numbers also indicate that fishers should be incentivized to provide high-quality fish at the right time of importance for optimal resource use. Increased competition also means that, over time, winning bids will be placed by the buyers that are the most capable of adding value and earning profits, which also contributes to optimal resource use. Findings also show to what extent factors such as lot size, quality grade, fishing method (bottom trawl, longline, Danish seine), and seasonality influence the probability of two or more participating bidders in auctions, which should be highly relevant information for fishers and policy makers.publishedVersio

Large-scale fisheries during the COVID-19 pandemic: The case of the oceangoing groundfish fleet in Norway

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Fishing methods for Atlantic cod and haddock: Quality and price versus costs

This study explores trade-offs between fish quality, fishing efficiency, costs and profitability across three different vessel groups in the Norwegian groundfish fishery, that is, vessels fishing with bottom trawls, longlines and Danish seines. The results of hedonic price analysis at the ex-vessel level of the value chain indicate substantial differences in fish quality as Atlantic cod caught with longlines obtain price premiums of 15.0 % and 12.6 % compared with bottom trawling and Danish seining, respectively, holding other variables constant. For haddock, longlining obtains a price premium of 20.0 % compared with Danish seining and 13.3 % compared with bottom trawling. However, despite better quality and prices, the costs of fishing are substantially higher for longliners than for bottom trawlers and Danish seiners, which explains the differences in profitability favoring the more technically efficient bottom trawlers and Danish seiners. Policy implications are discussed considering trade-offs between fish quality, ex-vessel prices and vessel profitability. In a highly regulated fishery such as the Norwegian groundfish fishery, with individual vessel and vessel group quotas based on historical fishing rights, policy intervention is important for optimal use of limited fish stocks but is not necessarily straightforward.publishedVersio

Large-scale fisheries during the COVID-19 pandemic: The case of the oceangoing groundfish fleet in Norway

Small-scale fisheries have received most of the attention in the literature investigating negative impacts of the COVID-19 pandemic on seafood production. Larger fishing vessels are often perceived to be more resilient as they are better able to alter harvest patterns in response to supply shocks than smaller, less mobile vessels. In addition, larger fishing vessels often deliver storable frozen products contributing to resiliency. The supply and demand shocks caused by the COVID-19 pandemic provides an opportunity to test this hypothesis and is investigated here on the large-scale groundfish fleet in Norway. The results indicate that during the first two whole years of the pandemic the impact on price was small, but also that there were several secondary effects showing how negative shocks in some supply chains/markets are overcome.publishedVersio

Norwegian Farmed Salmon: A Commodity in Need of Differentiation?

Despite much innovation and development in the Norwegian salmon industry, the focus has largely been on building volume and reducing costs. Limited attention has been paid to develop value added products and differentiation strategies in Norway to reap stable profits associated with such strategies. In depth-interviews with a supply chain containing Norwegian salmon producers, one exporter and one feed producer, industrial buyers representing two Polish processing companies and two German retailers, aimed to provide insight into why more differentiation is not happening in the Norwegian salmon industry. Results from this supply chain reveals lack of communication and asymmetric power-dependence relations between the Norwegian salmon business actors and their industrial buyers.publishedVersio

Certify or not? The effect of the MSC certification on the ex-vessel prices for Atlantic cod in Norway

There is strong evidence that ecolabeled seafood commands a price premium in the retail market in Northern European countries. At the same time, there is significant uncertainty as to whether these markups are passed on to the fishers. This is important because producer benefits are required for an ecolabel to provide incentives for sustainable fishery management and fishing practices. Therefore, we investigate whether fishers obtained price premiums for certified cod in Norway. A unique setting for this investigation was created when a part of the fishery, the one conducted within the Norwegian territorial waters, lost its certification by the Marine Stewardship Council (MSC), while it was maintained for the offshore part of the fishery. Using a difference-in-difference approach, analyzing a large and detailed dataset, we find that on average, there is no premium for certified cod, and that other factors are more important. When controlling for buyer types, the loss of the MSC certification resulted in a price reduction for cod sold to producers who make fillets for Northern European markets. However, we found no significant price effect for cod sold to the other buyer types. This highlights the difficulty of obtaining a price premium when there are alternative sources of the product

Provenance, depositional setting and diagenesis as keys to reservoir quality of the Lower Cretaceous in the SW Barents Sea

This study examines the role of the depositional environment for the final reservoir quality in four Lower Cretaceous sandstone reservoirs in the southwestern Barents Sea by linking facies to the distribution of primary textures, composition, and diagenetic alteration. Facies analysis reveals slope-to-basin-floor, distal shallow-marine, and deltaic depositional environments. The slope-to-basin-floor sandstone has the highest porosity of 3–19% (avg. 13%). It is attributed to good sorting, non-pervasive carbonate cementation that inhibited compaction and allowed for secondary porosity through later dissolution, and moderate clay infiltration that resulted in clay cutanes on grain rims and the precipitation of chlorite (which inhibited quartz growth). For the deltaic sandstone, moderate to fluctuating energy and sediment supply provided good conditions for mechanical clay infiltration and varying porosity of 2–18% (avg. 8%). The distal shallow-marine sandstone reservoir has the lowest porosity of 1–12% (avg. 7%). Based on its fine-grained and bioturbated character, deposition in a low-energy environment with low sediment supply seems likely. The combination of fine-grained lamina, interstitial matrix and bioturbation led to porosity reduction. Abundant mica and feldspar grains in the shallow-marine sandstone, partly a result of the provenance, and deep burial also resulted in extensive illitization. High mineralogical maturity, much monocrystalline quartz in the quartz-grain populations, and similar felsic chemical rock compositions for all facies associations and wells indicate similar source rocks with some variations. Abundant mechanically unstable mica makes the nearby Loppa High a plausible catchment, which is supported by the seismic geometries. This study demonstrates that the porosity evolution of the studied Lower Cretaceous sandstone reservoirs is determined mainly by the depositional environment despite minor provenance and major diagenetic variationspublishedVersio

The role of shelf morphology on storm-bed variability and stratigraphic architecture, Lower Cretaceous, Svalbard

The dominance of isotropic hummocky cross‐stratification, recording deposition solely by oscillatory flows, in many ancient storm‐dominated shoreface–shelf successions is enigmatic. Based on conventional sedimentological investigations, this study shows that storm deposits in three different and stratigraphically separated siliciclastic sediment wedges within the Lower Cretaceous succession in Svalbard record various depositional processes and principally contrasting sequence stratigraphic architectures. The lower wedge is characterized by low, but comparatively steeper, depositional dips than the middle and upper wedges, and records a change from storm‐dominated offshore transition – lower shoreface to storm‐dominated prodelta – distal delta front deposits. The occurrence of anisotropic hummocky cross‐stratification sandstone beds, scour‐and‐fill features of possible hyperpycnal‐flow origin, and wave‐modified turbidites within this part of the wedge suggests that the proximity to a fluvio‐deltaic system influenced the observed storm‐bed variability. The mudstone‐dominated part of the lower wedge records offshore shelf deposition below storm‐wave base. In the middle wedge, scours, gutter casts and anisotropic hummocky cross‐stratified storm beds occur in inferred distal settings in association with bathymetric steps situated across the platform break of retrogradationally stacked parasequences. These steps gave rise to localized, steeper‐gradient depositional dips which promoted the generation of basinward‐directed flows that occasionally scoured into the underlying seafloor. Storm‐wave and tidal current interaction promoted the development and migration of large‐scale, compound bedforms and smaller‐scale hummocky bedforms preserved as anisotropic hummocky cross‐stratification. The upper wedge consists of thick, seaward‐stepping successions of isotropic hummocky cross‐stratification‐bearing sandstone beds attributed to progradation across a shallow, gently dipping ramp‐type shelf. The associated distal facies are characterized by abundant lenticular, wave ripple cross‐laminated sandstone, suggesting that the basin floor was predominantly positioned above, but near, storm‐wave base. Consequently, shelf morphology and physiography, and the nature of the feeder system (for example, proximity to deltaic systems) are inferred to exert some control on storm‐bed variability and the resulting stratigraphic architecture

Microstructure and fluid flow in the vicinity of basin bounding faults in rifts – The Dombjerg Fault, NE Greenland rift system

Faults commonly form loci for high fluid flux in sedimentary basins, where fluids, rocks and deformation processes frequently interact. Here, we elucidate the interaction of fluid flow, diagenesis and deformation near basin-bounding faults in sedimentary basins through a study in the vicinity (0–3.5 km) of the Dombjerg Fault in the NE Greenland rift system. Due to fault-controlled fluid circulation, fault-proximal syn-rift clastics underwent pervasive calcite cementation, whereas uncemented clastics at some distance from the fault remained highly porous and friable. Correspondingly, two distinct deformation regimes developed to accommodate continued deformation: discrete brittle fractures formed in calcite cemented rocks, whereas cataclastic deformation bands formed in uncemented deposits. We show that low-permeable deformation bands forming in highly porous rocks were associated with localized host rock alteration, and chemical reduction of porosity along bands. In rocks with cementation-induced low porosity, brittle fractures created new pathways for fluids, but were subsequently filled with calcite. Occasionally, veins comprise multiple generations of microcrystalline calcite, likely precipitated from rapidly super-saturated fluids injected into the fractures. This suggests cemented deposits sealed uncemented compartments, where fluid overpressure developed. We conclude that compartmentalized flow regimes may form in fault-bounded basins, which has wide implications for assessments of potential carbon storage, hydrocarbon, groundwater, and geothermal site