Institute of

Sea Fisheries

Director

Secretariat

 

Herwigstraße 31

27572 Bremerhaven

Telephone: +49 471 94460 101

Fax: +49 471 94460 199

maria-isabel.koester@thuenen.de


Dr. Norbert Rohlf

Dr. Norbert  Rohlf
Address
Herwigstraße 31
27572 Bremerhaven
Phone
+49 471 94460 331
Fax
+49 471 94460 199
E-Mail
norbert.rohlf@thuenen.de

Research interests

  • Population dynamics of pelagic fish stocks
  • Early life stages of fishes
  • Ichthyoplankton and acoustic surveys
  • Stock-coordination for herring in the North Sea
  • Surveydesign

Assignments

  • Population dynamics and assessment of pelagic fish stocks (herring, mackerel, horse mackerel, blue whiting and sprat) in the North Sea and North Atlantic
  • Biological monitoring of German fisheries activities and derivation of protection measures for fish stocks
  • Conduction of international herring larvae surveys in the North Sea
  • Recruitment research: Investigation of fish eggs and larvae in terms of species composition and size

Educational background and employment

  • since 2006: Scientist at the Institute of Sea Fisheries
  • 2000 – 2006: Freelance work as consultant. Main focus on fish eggs, larvae surveys and video-aided image analyses for plankton identification
  • 2000: Dissertation. Doctor’s thesis title: „Verhaltensänderungen der Larven des Ostseedorsches (Gadus morhua callarias) während der Dottersackphase“ (in German)
  • 1994 – 2000: Scientist at the Institute of Marine Research in Kiel. Collaborate in projects on the impact of fisheries on fish stock recruitment in the Baltic. Performance of herring larvae surveys in the North Sea from 1998 onwards
  • 1994: Master of Science at the Christian-Albrechts-University in Kiel. Thesis title: „Wachstumsuntersuchungen an den Otolithen mariner Fischlarven“ (in German).

Working Groups and Committees

Working Group - CommitteeTasks
ICES
Herring Assessment Working Group (HAWG)The working group assess the status of different herring and sprat stocks in the North Sea, West of Scotland and in Irish and Celtic waters.
Working Group on Atlantic Fish Larvae and Egg Surveys (WGALES)The focus of this group is on fish eggs and larval development and early life strategies. It also serves as a general forum for discussion on matters concerning egg and larvae survey.
Working Group for Surveys of Ichthyoplankton in the North Sea and adjacent seas (WGSINS)Group members plan and execute six different Ichthyoplankton surveys in the North Sea and adjacent seas. They calculate biomass and recruitment indices for assessment purposes and define the standards in sampling, post-processing and species identification in the specific surveys.
Workshop on North Sea Stocks Management Strategy Evaluation (WKNSMSE)The group has evaluated different management strategies for key North Sea roundfish stocks.
Advice Drafting Group Bay of Biscay (ADGBBI)The group review the advice on fishing opportunities for Bay of Biscay and Iberian fish stocks, prepared by the relevant working group (WGBIE).