stocking density effects on growth and survival
Background The European flat oyster, Ostrea edulis , is of significant importance to the North-eastern Atlantic marine environment, from both a socio-economic and ecological point. Functionally extinct in the majority of its historical bio- geographic range, following a combination of over-fishing, disease outbreaks, and climatic changes; the protection, restoration and reintroduction of this species are in the focus of a growing number of mitigation initiatives. The RESTORE and PROCEED projects of the Alfred-Wegener Institute / Bundesamt für Naturschutz aim to reintroduce O. edulis into the German Bight using domestically grown ‘seed' oysters from our hatchery on Helgoland. Out-growing of hatchery spat to a suitable size for field deployment requires a nursery step, during which the spat is isolated from predators whilst having access to adequate food (phytoplankton) for growth.
Tasks The research objective of this thesis is toexamine differences in the biology, physiology and survival of spat oystersheld in a deep-water field nursery, compared to those in a controlledshore-based nursery, when stocked at a range of densities. Environmental datafrom both out-growing systems will be collected, including temperature,salinity and food availability, for use in determining the suitability andgrowth conditions of the deep-water nursery site. This research project will bebased on the island of Helgoland, Germany, and will involve a combination ofship-based field work, laboratory and hatchery work. It is envisaged thatfurther small-scale experimentation will be performed in parallel, examiningspecific biological and physiological functions (filtration, egestion, etc.) ofthe spat under a range of environmental conditions.
Requirements We are looking for a Master student in marine biology, maritime technologies or a related field.
Further Information All experimental work will be carried out on Helgoland, starting early 2023 and accompanying the production season in the Helgoland Oyster Hatchery.
You are interested? Then please send us your application with Cover letter & an CV (with all documents merged into one PDF file) by e-mail to: Bérenger Colsoul (Berenger.Colsoul@awi.de) and/or Dr. Bernadette Pogoda (Bernadette.Pogoda@awi.de).
For further information please contact Bérenger Colsoul (Berenger.Colsoul@awi.de, +49 (0151) 63351428) Dr. Bernadette Pogoda (Bernadette.Pogoda@awi.de, +49 (0471) 4831-2710)
and/or visit our homepage https: // www. awi.de/en/science/biosciences/shelf-sea-system-ecology/main- research-focus/european-oyster/proceed/translate-to-english-hatchery.html