Testing early life connectivity supplying a marine fishery around the Falkland Islands

Ashford, Julian R.
Fach Salihoğlu, Bettina Andrea
Arkhipkin, Alexander I.
Jones, Cynthia M.
We used a wind-driven global circulation model to build spatially explicit predictions from rival hypotheses concerning advective supply of Patagonian toothfish (Dissostichus eleginoides) to a trawl fishery around the Falkland Islands, and tested the predictions using chemistry recorded in the otoliths of fish caught in the fishery. Model simulations indicated transport pathways from spawning aggregations off southern Chile to both the north and south of the fishing area. In contrast, simulated particles released from spawning aggregations around Burdwood Bank were transported to the south of the fishing area but not to the north, becoming fully entrained in the Subantarctic Front instead. Spatial heterogeneity in the chemistry laid down in the otolith nuclei during early life discounted the hypothesis of a single population with a spawning area on Burdwood Bank, and indicated that fish assemblages are structured by large-scale transport from both southern Chile and Burdwood Bank. By linking fish explicitly to their physical environment, the two techniques can help distinguish the life cycle trajectories necessary for populations to persist, and elucidate the interactions between hydrography and life history that structure the fish assemblages on which marine fisheries depend.


Testing early life connectivity using otolith chemistry and particle-tracking simulations
Ashford, Julian; La Mesa, Mario; Fach Salihoğlu, Bettina Andrea; Jones, Christopher; Everson, Inigo (2010-08-01)
We measured the otolith chemistry of adult Scotia Sea icefish (Chaenocephalus aceratus), a species with a long pelagic larval phase, along the Antarctic Circumpolar Current (ACC) and compared the chemistry with simulated particle transport using a circulation model. Material laid down in otolith nuclei during early life showed (i) strong heterogeneity between the Antarctic Peninsula and South Georgia consistent with a population boundary, (ii) evidence of finer-scale heterogeneity between sampling areas on ...
Transport of Antarctic krill (Euphausia superba) across the Scotia Sea. Part II. Krill growth and survival
Fach Salihoğlu, Bettina Andrea; Murphy, Eugene J. (2006-06-01)
A time-dependent, size-structured, physiologically based krill growth model was used in conjunction with a circulation model to test the hypothesis that Antarctic krill (Euphausia superba) populations at South Georgia are sustained by import of individuals from upstream regions. Surface phytoplankton concentrations along the simulated drifter trajectories were extracted from historical Coastal Zone Color Scanner (CZCS) measurements and sea ice biota concentrations were calculated from sea ice concentration ...
Implementation of Antarctic Krill into the Ocean-Ecosystem Model FESOM-REcoM-2 and its Effects on Southern Ocean Biogeochemistry.
Karakus, Onur; Hauck, Judith; Völker, Christoph; Fach Salihoğlu, Bettina Andrea; Hagen, Wilhelm (2020-01-16)
In this study, a three-dimensional, coupled ocean ecosystem model (FESOM- REcoM2) is used to investigate the effect of krill on the biogeochemistry of the Southern Ocean. The implementation of Antarctic krill in the model was done in three steps. 1) A second zooplankton group was implemented, which grazes on diatoms, mesozooplankton and nanophytoplankton (in order of descending preference). 2) A new detritus group was added to the model, which represents faster-sinking krill faecal pellets. 3) The grazing i...
Assessment of temporal variation and sources of PCBs in the sediments of Mediterranean Sea, Mersin Bay, Turkey
Gedik, Kadir; İmamoğlu, İpek (Elsevier BV, 2011-01-01)
Information on temporal distribution of polychlorinated biphenyls (PCBs) in the coastal sediments of Mediterranean Sea, Mersin was compiled using data published between 1980 and 2009, and the present study. The first congener specific PCB results from the region yield concentration levels of Sigma(41) PCBs in sediments ranging from 0.61 to 1.04 ng g(-1). Sediment profiles show penta-, hexa- and hepta-chlorobiphenyls, specifically, #149 and 153 as the most abundant congeners in all samples. Comparison of tot...
Simulations of the Black Sea pelagic ecosystem by 1-D, vertically resolved, physical-biochemical models
Oguz, T; Ducklow, HW; Malanotte-Rizzoli, P; Murray, JW (Wiley, 1998-09-01)
The present paper summarizes the results of several simulations of the central Black Sea pelagic food web using three different 1-D, physical-biochemical, water column process models. The most simplified, five-compartment version is used to explore the robust biological features of the ecosystem and the role of upper-layer physics on the evolution of the euphotic zone biological processes. The other models, introducing additional biological complexities, show how these biologically structured models become ...
Citation Formats
J. R. Ashford, B. A. Fach Salihoğlu, A. I. Arkhipkin, and C. M. Jones, “Testing early life connectivity supplying a marine fishery around the Falkland Islands,” FISHERIES RESEARCH, pp. 144–152, 2012, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/31221.