Simulating vertical turbulent dispersal with finite volumes and binned random walks

Thygesen, Uffe Høgsbro; Ådlandsvik, Bjørn

doi:10.3354/meps06975

Cited by 36 publications

(25 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The same was included when using the NorKyst800 as forcing for particle dispersal. Vertical distribution of eggs is based on individual egg size and density (Sundby, 1983), modeled ocean densities and levels of turbulence in the water column at the individual time-varying location of each egg (based on Thygesen and Ådlandsvik, 2007;utilized in e.g., Opdal et al, 2011;Röhrs et al, 2014). The larval and juvenile growth function is taken from Folkvord (2005) and based on laboratory experiments for a range of temperatures under constant satiated feeding of the offspring.…”

Section: Individual-based Modelmentioning

confidence: 99%

The Northeast Greenland Shelf as a Potential Habitat for the Northeast Arctic Cod

et al. 2017

View full text Add to dashboard Cite

Observations (1978)(1979)(1980)(1981)(1982)(1983)(1984)(1985)(1986)(1987)(1988)(1989)(1990)(1991) of distributions of pelagic juvenile Northeast Arctic cod (Gadus morhua L.) show that up to 1/3 of the year class are dispersed off the continental shelf and into the deep Norwegian Sea while on the way from the spring-spawning areas along the Norwegian coast to the autumn-settlement areas in the Barents Sea. The fate of this variable fraction of pelagic juveniles off-shelf has been an open question ever since Johan Hjort's (1914) seminal work. We have examined both the mechanisms causing offspring off-shelf transport, and their subsequent destiny using an individual-based biophysical model applied to quantify growth and dispersal. Our results show, consistently with the observations, that total off-shelf transport is highly variable between years and may be up to 27.4%. Offspring from spawning grounds around Lofoten have a higher chance of being displaced off the shelf. The off-shelf transport is dominated by episodic events where frequencies and dates vary between years. Northeasterly wind conditions over a 3-7-day period prior to the off-shelf events are a good proxy for dispersal of offspring off the shelf. Offspring transported into the open ocean are on average carried along three following routes: back onto the adjacent eastern shelves and into the Barents Sea (36.9%), recirculating within the Lofoten Basin (60.7%), or drifting northwest to the northeast Greenland shelf (2.4%). For the latter fraction the transport may exceed 12% depending on year. Recent investigations have discovered distributions of young cod on the northeast Greenland shelf indicating that conditions may support survival for Northeast Arctic cod offspring.

show abstract

Section: Individual-based Modelmentioning

confidence: 99%

The Northeast Greenland Shelf as a Potential Habitat for the Northeast Arctic Cod

et al. 2017

View full text Add to dashboard Cite

show abstract

“…The individual-based model accounts for egg development according to ambient temperature, and the vertical distribution is determined by buoyancy and turbulence (Sundby 1997;Thygesen and Ådlandsvik 2007). The eggs hatch into larvae of length 4.0 mm, based on reported length 2 days after hatch (Otterlei et al 1999), and mass of 0.0448 mg after about 20 days (D) depending on the ambient temperature (T in°Celsius) according to ln D = 3.65 -0.145T (Ellertsen et al 1987).…”

Section: Individual-based Model For Early Life Stagesmentioning

confidence: 99%

Reproductive strategy of a migratory fish stock: implications of spatial variations in natural mortality

Langangen

Ottersen

Ciannelli

et al. 2016

Can. J. Fish. Aquat. Sci.

View full text Add to dashboard Cite

Abstract:We investigate how the reproductive strategy in a migratory marine fish may be influenced by spatial variations in mortality in early life stages. In particular, we examine how spawning time and location affect offspring survival and growth. A drift model for early life stages (eggs to age 1) of the Barents Sea cod (Gadus morhua) is combined with empirical estimates of spatial variation in mortality at two different life stages. We examine seasonal and interannual differences in survival and growth in offspring originating from two spawning grounds, with the central site requiring higher migration distance, and hence cost, than the northern site. When accounting for spatially explicit mortality fields, central and northern spawned offspring have about equal survival, as do early and late spawned offspring. Furthermore, central spawned offspring grow faster and are likely to reach a larger size compared with northern spawned offspring. Our results indicate that the fitness benefit of southward migration in the Barents Sea cod is not mainly due to higher early survival of offspring, but rather due to effects of offspring acquiring a larger size.Résumé : Nous examinons l'influence potentielle des variations spatiales de la mortalité aux premières étapes du cycle de vie sur la stratégie de reproduction chez un poisson marin migrateur. Nous nous penchons plus particulièrement sur l'effet du moment et de lieu du frai sur la survie et la croissance de la progéniture. Un modèle de dérive pour les premières étapes du cycle biologique (des oeufs à l'âge de 1 an) de la morue (Gadus morhua) de la mer de Barents est combiné à des estimations empiriques de la variation spatiale de la mortalité à deux étapes différentes du cycle de vie. Nous examinons les variations saisonnières et interannuelles de la survie et de la croissance de progénitures issues de deux lieux de frai, un site central nécessitant une plus grande distance de migration et donc un coût de migration plus important que l'autre site, plus septentrional. En tenant compte de champs de mortalité spatialement explicites, les progénitures issues des sites central et septentrional présentent des taux de survie à peu près égaux, tout comme les progénitures produites vers le début et la fin de la période de frai. En outre, la progéniture issue du site central grandit plus rapidement et est plus susceptible d'atteindre de plus grandes tailles que la progéniture issue du site septentrional. Nos résultats indiquent que l'avantage sur le plan de l'aptitude que confère la migration vers le sud chez la morue de la mer de Barents ne découle pas principalement d'un taux de survie précoce plus important de la progéniture, mais plutôt des effets de l'atteinte d'une plus grande taille par la progéniture. [Traduit par la Rédaction]

show abstract

“…In short, the eggs develop according to spatiotemporally resolved ambient temperature from the model and the developmental times reported by Martell, Kieffer, and Trippel (). The vertical distribution is determined by buoyance and turbulence (Sundby, ; Thygesen & Ådlandsvik, ). We released particles representing eggs on the known spawning grounds of haddock (Figure ).…”

Section: Methodsmentioning

confidence: 99%

Multi‐decadal variations in spawning ground use in Northeast Arctic haddock (Melanogrammus aeglefinus)

Langangen

Stige

Kvile

et al. 2018

Fisheries Oceanography

View full text Add to dashboard Cite

Despite the importance both in an ecological and management context, much uncertainty remains about the underlying factors controlling spawning ground use in marine fish. Here, we investigate how spawning ground use of Northeast Arctic (NEA) haddock (Melanogrammus aeglefinus) has changed over time. By combining data from a Soviet‐Russian egg survey conducted over a 35 year period (1959–1993) with a biophysical drift model, we estimate annual median spawning latitudes of NEA haddock. Furthermore, we test for statistical association between the median latitude of spawning and covariates that are candidates for shaping the spawning distribution of haddock. The results indicate no association with temperature, as measured at the Kola transect, or demographic structure, as measured by the mean weight of spawners. However, we find a positive and significant association between spawning latitude and spawning stock biomass, indicating that density‐dependence may be more important in shaping spawning location than other factors such as temperature and demographic structure. A potential mechanism for the reported effect of spawning stock biomass may act through the distribution at the feeding grounds, which is reported to expand north‐ and eastwards at high population density.

show abstract

Simulating vertical turbulent dispersal with finite volumes and binned random walks

Cited by 36 publications

References 16 publications

The Northeast Greenland Shelf as a Potential Habitat for the Northeast Arctic Cod

The Northeast Greenland Shelf as a Potential Habitat for the Northeast Arctic Cod

Reproductive strategy of a migratory fish stock: implications of spatial variations in natural mortality

Multi‐decadal variations in spawning ground use in Northeast Arctic haddock (Melanogrammus aeglefinus)

Contact Info

Product

Resources

About