FS ANTON DOHRN

Dr. Alshuth participated in many fisheries research expeditions to the Atlantic, Baltic and North Seas. This page features one of Dr. Alshuth’s fisheries expeditions onboard the German fisheries research vessel ANTON DOHRN of the Institute for Marine Fisheries Research, located in Bremerhaven (Germany). On this four-week expedition, Dr. Alshuth and an international fisheries biologist research team examined the benthic fish population densities in the Baltic Sea, conducted stomach content analysis of cod, and examined their reproduction biology. Special emphasis of this fisheries research expedition was fish pathology and parasitology, examining benthic fish for diseases, deformities and parasites of benthic fish, in particular flatfish species and cod in response to anthropogenic marine impacts on the Baltic Sea ecosystem. As part of this interdisciplinary marine research, Dr. Alshuth conducted a variety of physical and chemical oceanographic studies, including the vertical temperature, salinity and dissolved oxygen profile analysis, collecting water samples from different depths with Niskin Bottles, and using physical CTD probes for further analysis of physical and chemical oceanographic parameters onboard the research vessel. The oceanographic research program included evaluation of expedition samples, identification, distribution and abundance of benthic fish communities, statistical evaluation and preparation of research reports, and publications including:

Alshuth, S. 1989. The worm is still in there. Fish parasites (German – Text and Photography). LOGO 4/5, 44-45.

Click on any picture below to start slide show.

BALTIC SEA EXPEDITION

FS ANTON DOHRN in Baltic Sea 

FS ANTON DOHRN - Baltic Sea expedition chart - Artwork: S. Alshuth

Cod fish population study. Cod were collected with bottom trawls

Fish biologists research team sorting benthic fish from bottom trawl

Dr. Alshuth and fish biologists research team examining cod for parasitic Lernaeocera found in the gills

Cod fish population density study: Examining weight to length ratios 

Cod and flatfish population study - collected with bottom trawls.

Baltic fish population density and biomass study onboard FS ANTON DOHRN

Oceanographic parameters tested with physical CTD probe and Niskin Bottle sampler for vertical temperature, salinity and oxygen profile analysis

Examining fish parasite infestations

Cod fish pathology & parasitology study: Examinng cod for tumors and endoparasitic Cryptocotyle trematoda 

Fish biologists research team examining cod’s skeletal deformation - enlarged & short skull & deformed and abnormal spines

Examining cod fish diseases: Exophthalmus - enlarged eyes

Examining fish parasites and diseases, such as papillomas and lymphocystis

Parasitic Lernaeenicus encrasicoli attached to adult sprat Sprattus sprattus

Dr. Alshuth studying pathologic tumors on flatfish species - tumor seen here on Dab Limanda limanda

Infestations of parasitic Lymphocystis on flounder (Platichthys flesus)

Fish biologist Dr. Alshuth examining fish parasites and diseases, such as epidermal papillomas seen here on flatfish

Studying fish pathology and parasites of flatfish species - open tumors on flounder (Platichthyes flesus)

Parasitic Cryptocotyle lingua infesting tissues of pelagic pollock (Pollachius virens)

Parasitic Lernaeocera branchialis attached to the gills of pelagic pollock (Pollachius virens)

Examining cod’s skeletal deformation - enlarged & short skulls

FS ANTON DOHRN reaches eastern Baltic: Destination Gdansk harbour for exchange of the scientific research crew

BALTIC SEA EXPEDITION