Live transport of the green sea urchin (Strongylocentrotus droebachiensis) in air and immersed in seawater and the impact on subsequent roe enhancement after in-water transport

publishedVersio

Effect of Season and Increased Temperature on Survival, Roe Enhancement, and Reproductive Cycle of the Green Sea Urchin (Strongylocentrotus droebachiensis) Collected from Four Relatively Close Sites in Northern Norway

A series of three trials were conducted in the North of Norway at different times of the year. The trials consisted of harvesting sea urchins from four sites, situated within 5 km of each other and then holding them in land-based enhancement facilities. They were held at ambient seawater temperatures as well as ambient plus 3.0°C. Samples were taken from the wild at the time of collection and at the end of the enhancement period as well as from the enhanced sea urchins from each site. Results showed that utilising the sea urchins from a variety of sites, even from areas where there is an abundance of sea urchins (sea urchin barrens) and the Gonad Index (GI) is almost always low, is viable in terms of the final, post roe enhancement GI. The results of the study indicate that differences in initial and final GI and the increase in GI between the sites, despite the relatively close proximity, show site selection is most likely not as important as ease of harvesting and sea urchin availability and the positive environmental impact from removal of sea urchins and these are the factors that harvesting strategies should focus on. The study has shown that it is possible to have a relatively consistent roe enhancement from S. droebachiensis from the North of Norway regardless of seasonality (time of year), site selection, and initial GI. Relatively small changes (up to 3°C) in the seawater temperature appear to have a slightly negative impact on enhancement efforts. However, this may vary when larger differences in temperature are experienced.Effect of Season and Increased Temperature on Survival, Roe Enhancement, and Reproductive Cycle of the Green Sea Urchin (Strongylocentrotus droebachiensis) Collected from Four Relatively Close Sites in Northern NorwaypublishedVersio

Does waste feed from salmon farming affect the quality of saithe (Pollachius virens L.) attracted to fish farms?

Salmon farms attract large amounts of wild fish, which prey on uneaten feed pellets. The modified diet of the wild fish aggregating at salmon farms may reduce the flesh quality of the fish, influencing the local fisheries. We compared the quality of saithe (Pollachius virens) captured near (farm associated—FA) or more than 5 km away (un‐associated—UA) from salmon farms in Norway. The fish were captured during summer, autumn and spring using two commercial fishing methods (jigging and bottom nets). Overall, the fillet quality of FA saithe was good, although it was clearly reduced for almost 10% of the catch. Moreover, the quality of the FA saithe was significantly reduced compared with UA saithe, but the differences were small. Our results also showed that fish caught with jigging had better quality than fish caught with nets, and that fish that died in the nets were of lower quality than fish that were alive after hauling. There was no clear variation among seasons in fillet quality. Although no major and overall differences in quality were found between FA and UA saithe, reduced quality for even a modest proportion of the fish may influence the value of the total catch.The study was funded by the Norwegian Seafood Research Fund through the ProCoEx project (Project number: 900772) and the Norwegian Research Council through the project ‘ECOCOAST’. Kilian Toledo‐Guedes was supported by a grant from Iceland, Liechtenstein and Norway through the EEA Financial Mechanism (ES07‐EEA Grants, 013‐ABEL‐IM‐2013), operated by Universidad Complutense de Madrid, and Juan de la Cierva Program FJCI‐2014‐20100 and IJCI‐2017‐34174 from Ministerio de Ciencia, Innovación y Universidades

A novel miniaturized biosensor for monitoring atlantic salmon swimming activity and respiratory frequency

Good fish welfare is one of the prerequisites for sustainable aquaculture. Knowing how fish respond to the production conditions would allow us to better understand their biology and to further optimize production. The new miniaturized biosensor AEFishBIT was successfully used to monitor individual physical activity and respiratory frequency of two Mediterranean farmed fish species (gilthead sea bream and European sea bass). In this study, we aimed to test the use of AEFishBIT to monitor the performance of Atlantic salmon under experimental conditions. An adapted tagging procedure for salmon was developed and used to record salmon responses to handling and changing light conditions. AEFishBIT data showed a stabilization of swimming activity 8 h after handling and tagging with changes in activity or activity and respiratory quotient after changes in light intensity regimes. The results of this study supported the use of AEFishBIT to generate new behavior insights in Atlantic salmon culture.publishedVersio

Proactive avoidance behaviour and pace-of-life syndrome in Atlantic salmon

Individuals in a fish population differ in key life history traits such as growth rate and body size. This raises the question if such traits cluster along a fast-slow growth continuum according to a pace-of-life syndrome (POLS). Fish species like salmonids may develop a bimodal size distribution, providing an opportunity to study the relationships between individual growth and behavioural responsiveness. Here we test whether proactive characteristics (bold behaviour coupled with low post-stress cortisol production) are related to fast growth and developmental rate in Atlantic salmon (Salmo salar). Boldness was tested in a highly controlled two-tank hypoxia test were oxygen levels were gradually decreased in one of the tanks. All fish became inactive close to the bottom at 70% oxygen saturation. At oxygen saturation level of 40% a fraction of the fish actively sought out to avoid hypoxia. A proactive stress coping style was verified by lower cortisol response to a standardized stressor. Two distinct clusters of bimodal growth trajectories were identified, with fast growth and early smoltification in 80% of the total population. There was a higher frequency of proactive individuals in this fast-developing fraction of fish. The smolts were associated with higher post-stress plasma cortisol than parr, and the proactive smolts leaving hypoxia had significant lower post-stress cortisol than the stayers. The study demonstrated a link between a proactive coping and fast growth and developmental ratio, and suggests that selection for domestic production traits promotes this trait cluster

Landing and delivery of live haddock - optimal slaughter, cooling and processing with regard to product quality

Når en sammenligner den levendeleverte hysa med tradisjonelt levert hyse på slakte/leveringsdagen, så er det store forskjeller med hensyn på kvalitet. Den levendeleverte hysa som blir pre-rigor prosessert har veldig lite spalting, god konsistens og lite blod i filetene, dette i motsetning til den tradisjonelt leverte hysen fra en annen båt. Når fisken lagres videre i 1 døgn så blir disse forskjellene litt mindre, men levendelevert hyse kommer klart best ut her også, noe som viser at den tåler lagring bedre. For å oppnå best mulig kvalitet er det viktig at levendelevert hyse prosesseres raskest mulig. Noen av de viktigste funnene så langt i prosjektet er: • Det er mulig å levere levende hyse rett til landanlegg for kontrollert slakting og videre pre-rigor prosessering. • De største utfordringene med spalting, konsistens og blod kan minimeres med levendelevering og pre-rigor filetering. • Produksjonsutbytte øker og samtidig vil andelen som kan benyttes til høykvalitetsprodukter øke kraftig sammenlignet med tradisjonell produksjon. • Kvalitetsforbedringen ser ut til å opprettholdes under lagring som filet.Landing and delivery of live haddock - optimal slaughter, cooling and processing with regard to product qualitypublishedVersio

Transportsystemer for kråkeboller - for land, sjø og luft (Aktivitet A6.4.1 i NPS URCHIN prosjekt)

This report gives a brief introduction to the URCHIN project, funded by the Northern Peripheries and Arctic Programme (NPA) including the aims of this study. The authors recommend that the maximum period for transporting live sea urchins for use in subsequent roe enhancement trial, using the dry techniques described in this report would be between 14 and 44 hrs (depending on temperature). The results from the immersion transport trials show that transporting sea urchins in chilled, aerated seawater systems will be suitable for sea urchins for periods of at least 22 days. If ammonia-stripping (denitrifying) capacity is included into the transport system, then transportation times may be significantly longer. The average sea urchin unionized ammonia (UIA) production in chilled (6.6oC) and aerated seawater holding systems is 1.34625-5 kg urchins/day/litre. All sea urchins held in novel spray holding systems died within 4-5 days. Although spray-holding systems are effective for live holding of various species of shellfish the results of these short trials indicate that they are not suitable for live holding and transportation of sea urchins. If sea urchins are delivered alive and ready for processing or immediate consumption, then the airfreight packing techniques described in this report is sufficient for at least up to 44hrs transport. If sea urchins are required for storage in a holding system and remain alive for an extended period, then the techniques used in this trial are effective up to 34hrs transport.Sea Urchin transportation systems for land, sea and air (Activity A6.4.1 of the NPA URCHIN project)Transportsystemer for kråkeboller - for land, sjø og luft (Aktivitet A6.4.1 i NPS URCHIN prosjekt)publishedVersio

Tilstandsutvikling på vegnettet : Virkninger av endret klima på sporutvikling på veger med bituminøst dekke

Rapporten inngår i en serie rapporter fra FoU‐prosjektet “Klima og transport”, etatsprosjekt 2007‐2010.Rapporten inngår i en serie rapporter fra FoU‐prosjektet “Klima og transport”, etatsprosjekt 2007‐2010. Hensikten med prosjektet er å forbedre rutiner og regelverk for planlegging, prosjektering, bygging, drift og vedlikehold av vegnettet som svar på endrede klimaforhold. Rapporten inneholder beregninger og vurderinger av forventet endring i det norske vegnettets tilstandsutvikling som følge av endret klima. For samlet rv og fv vil klimaendringer gi en gjennomsnittlig reduksjon i forventet sporutvikling i størrelsesorden 0,2 mm/år, tilsvarende en økning i dekkelevetiden på ca 13 - 16 %. Dette tilsvarer en besparelse i dekkevedlikeholdskostnadene på 150 - 200 mill. kr/år. En antatt reduksjon i dybde til grunnvannstanden vil gi en økning i dekkevedlikeholdskostnadene