Biochemically based modeling study of Antarctic krill Euphausia superba growth and development

Fach Salihoğlu, Bettina Andrea
Wolf-Gladrow, Dieter
Bathmann, Ulrich
A biochemical model of Antarctic krill Euphausia superba was developed to investigate the physiological mechanisms which enable krill to survive winter, when food is scarce. In this modeling approach data sets on the biochemical composition of krill and its food sources are combined into a model that takes food quality into account rather than just food availability during different seasons. Krill is defined in terms of protein, neutral lipid, polar lipid, carbohydrate, chitin, and ash content, and the model tracks krill neutral lipid content separately from weight. The model includes parameterizations of filtration, ingestion, and metabolic processes which determine krill growth rate. Initial ratios of protein, neutral lipid, polar lipid, carbohydrate and ash change in chitin response to the biochemical composition of food as krill grows. Model results show that a diet of phytoplankton food alone may be sufficient for krill to grow to observed sizes but may not be sufficient to provide the summer lipid resources that are observed in the field and that are necessary for krill to reproduce and survive winter. The inclusion of sea ice algae as an additional food is beneficial for krill at the end of winter but does not significantly change summer krill lipid content. However, the amount of lipids accumulated within krill increases significantly when krill feeds on lipid-rich heterotrophic food, which points to the importance of carnivory, even in times when phytoplankton food is available. The strategy of combusting body components to produce energy (shrinking) is found to provide the greatest source of energy for krill of all sizes during times of prolonged starvation.


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 ...
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Salihoğlu, Barış; Hofmann, EE (2001-05-01)
An individual-based model is developed to examine mechanisms that potentially underlie the observed constancy in fledging weight (2.8-3.2 kg) of Adelie (4Pygoscelis adeliae) penguin chicks, in spite of large variability in the abundance of Antarctic krill (Euphausia superba), the primary food source. The model describes the energetic requirements of the chick. with growth resulting from the difference between assimilated energy and respiration. Parameterizations of these metabolic processes are based upon e...
Microplastic consumption and physiological response in Acartia clausi and Centropages typicus: Possible roles of feeding mechanisms
Svetlichny, Leonid; Isinibilir, Melek; Mykitchak, Taras; Eryalcin, Kamil Mert; Turkeri, Ezgi E.; Yuksel, Esin; Kıdeyş, Ahmet Erkan (2021-03-01)
Multi-day experiments were carried out with two Marmara Sea calanoid copepod species: Acartia clausi and Centropages typicus, to assess the possible role of the type of feeding on the consumption of microplastics and its influence on the rate of energy metabolism of these species. In a mixture of microplastic beads (6 mu m diameter) and algae Rhodomonas salina (5-10 mu m size range) with equal concentrations of about 5000 cells/beads mL(-1) the ambush feeder A. clausi consumed almost 5 times less microplast...
Seasonal variation in body composition, metabolic activity, feeding, and growth of adult krill Euphausia superba in the Lazarev Sea
Meyer, Bettina; Auerswald, Lutz; Siegel, Volker; Spahic, Susanne; Pape, Carsten; Fach Salihoğlu, Bettina Andrea; Teschke, Mathias; Lopata, Andreas L.; Fuentes, Veronica (2010-01-01)
We investigated physiological parameters (elemental and biochemical composition, metabolic rates, feeding activity and growth) of adult Antarctic krill in the Lazarev Sea in late spring (December), mid autumn (April) and mid winter (July and August) to evaluate proposed hypotheses of overwintering mechanisms. Our major observations are: (1) respiration rates were reduced by 30 to 50% in autumn and winter, compared to values in late spring; (2) feeding activity was reduced by 80 to 86% in autumn and winter, ...
Temporal and spatial changes in the abundance and biomass of pico (heterotrophic bacteria & synechococcus) and nanoplankton (flagellates) of the Mersin Bay – relationships with ambient physical, chemical and biological parameters
Gazihan Akoğlu, Ayşe; Uysal, Zahit; Department of Marine Biology and Fisheries (2011)
The eastern Mediterranean has been known as the most oligotrophic water body among the worlds oceans and as a result of limited nutrient inputs from terrestrial sources primary productivity and plankton succession are restricted by lack of nutrients especially by phosphorus and nitrogen. Within this domain, Mersin bay forms a so called hot spot (highly sensitive) area where a sharp contrast exists between the coastal area supplied by land-based nutrient sources and the nutrient limited open sea. Excess nutr...
Citation Formats
B. A. Fach Salihoğlu, D. Wolf-Gladrow, and U. Bathmann, “Biochemically based modeling study of Antarctic krill Euphausia superba growth and development,” MARINE ECOLOGY PROGRESS SERIES, pp. 147–161, 2008, Accessed: 00, 2020. [Online]. Available: