Alexander Kempf (Dipl.Biol.)

Phone: +49(0)40 - 42383 6611
Fax: +49(0)40 - 42383 6618
University of Hamburg
Institute for Hydrobiology and Fisheries Science
Olbersweg 24
22767 Hamburg
Germany

Research interests

I am working in the field of multi species stock assessment that takes predator-prey relationships into account in contrast to standard single species assessment techniques. One main focus thereby is to detect structural uncertainties in current multispecies models, like MSVPA or SMS. These structural uncertainties can lead to serious problems in fish stock assessment and make predictions of fish stocks unreliable. The question whether fish stocks will increase or decrease in the near future can be answered in both directions depending on the parameterisation of the diet selection model and the status of the food web, for example. Therefore, my second research focus is to develop better diet selection models. Especially the influence of changes in predator-prey overlap over time on the diet selection of North sea fish predators is still insufficiently understood.

Educational Background

University education

1996 –2003: Biology studies at the Christian-Albrechts-Universität in Kiel

2003: Diploma under the supervision of Prof. Schnack with fisheries science as main subject
Thesis: "Auswahl und Verfügbarkeit von Nahrungsorganismen als kritischer Faktor in der Mehrartenmodellierung – ein Beispiel aus der MSVPA in der Nordsee".

2003 ongoing: PhD-student in the EU -Project BECAUSE

Projects

2004 - 2007: BECAUSE (Critical Interactions BEtween Species and their Implications for a PreCAUtionary FiSheries Management in a variable Environment - a Modelling Approach

Publications

Research articles (peer-reviewed)

Kempf, A., Floeter, J. and Temming A. (2006) Decadal changes in the North Sea food web between 1981 and 1991 - implications for fish stock assessment. Can J. Fish. Aquat. Sci. 63: 2586-2602.

Floeter, J., Kempf, A., Vinther, M., C. Schrum, and Temming A. (2005) Grey gurnard (Eutrigla gurnadus (L.)) in the North Sea: an emerging key predator ? Can J. Fish. Aquat. Sci. 62: 1853-1864.

Other literature

Kempf, A.; Floeter, J.; Temming, A. 2005: Are we able to model 0-group fish? ICES Study Group on Multispecies Assessment in the North Sea [SGMSNS] 2005 Kopenhagen, Working Document

Floeter, J., Kempf, A. and A. Temming 2005: Evaluating the effects of survey index calculation, and changes in survey coverage on whiting IBTS quarter 1 index trends. Working Document for the Study Group on Stock Identity and Management Units of Whiting [SGSIMUW] 78pp.

Kempf, A.; Floeter, J.; Temming, A. 2003: Sensitivity of 4M predictions to the use of different stomach data sets, a case study on a potential North Sea gadoid recovery plan. ICES Study Group on Multispecies Assessment in the North Sea [SGMSNS] 2003 Bergen, Working Document

Selected Oral & Poster Presentations

Kempf, A.; Floeter, J.; Temming, A.: Diet selection of North Sea cod and whiting. BECAUSE meeting, Brest, 2005.

Kempf, A.; Vinther, M.; Floeter, J.; Temming, A.: Evaluation of a North Sea cod recovery plan taking into account biological interactions, Workshop on Harvest Control Rules, Bergen, 2004