Skip to main content
[Translate to English:]
[Translate to English:]
Institute of

OF Baltic Sea Fisheries

Ongoing projects • Living marine resources

Processing of German fisheries data for use in stock assessment of commercially used stocks in the Baltic Sea

Stock assessment involves fisheries data from all countries around the Baltic Sea. To ensure that the different national fisheries data can be smoothly merged into one single data set, sophisticated preliminary work from each fishery research institute is required – also from us.

More
Processing of German fisheries data for use in stock assessment of commercially used stocks in the Baltic Sea

Coordination of data collection from commerical fisheries in the Baltic Sea

The Thünen institute of Baltic Sea Fisheries does not only data about fish stocks in the Baltic Sea, but is also involved in international cooperation, e.g. with the EU and other Baltic Sea countries.

More
Coordination of data collection from commerical fisheries in the Baltic Sea

From a fish sample to stock assessment

Population models want to be fed with numbers of fish caught. However, at the landing site the fisher only report the landed weight, not the numbers of landed fish. Our expertise is to convert landing weights of the fisheries into numbers of herring or cod to provide the stock assessment models with the appropriate data feed.

More
From a fish sample to stock assessment

Age validation studies on wild fish: basis for accurate age determination

We would like to know the age of a fish as precisely and accurately as possible. Since fish do not swim around with an identification card, we have to interpret the ring structures in their ear stones (otoliths). To verify the relationship between the lighter and darker rings in the otoliths of fish and the true fish age, we carry out age validation experiments on wild fish.

More
Age validation studies on wild fish: basis for accurate age determination

What is the catch of gillnet fishermen?

The gillnet fishery is a central pillar of the German fisheries in the Baltic Sea. We regularly sample the catches and by-catches on board of gillnetters.

More
What is the catch of gillnet fishermen?

Fisheries research surveys: Monitoring of fish communities

Eine Seefahrt, die ist lustig… A research vessel cruise is mainly hard work onboard at sea, according to a fixed station grid and a tight schedule, under almost any weather condition. Specialized knowledge, routine and perseverance are required here.

More
Fisheries research surveys: Monitoring of fish communities

Improved calculations with fish data

A fish species forms different populations in its distribution area. These populations are called "stocks" in fisheries biology. The fish stocks of a species differ considerably in part because they are adapted to the particular environmental conditions of the marine area in which they live. We have more information for one stock and less for another, and stocks can have different levels of productivity. To account for these differences, we try to adapt population models to individual stocks in order to improve catch predictions.

More
Improved calculations with fish data

Fishes of the Baltic Sea - counted once yearly

What is the status of a commercially used fish stock in the Baltic Sea – and how does it develop? Given that most stocks are “shared stocks”, this question is raised annually and can only be answered in cooperation with other Baltic Sea countries. The answer is highly important for both fishing industry and anglers, and conservationist.

More
Fishes of the Baltic Sea - counted once yearly

Science onboard of German fishing vessels: Catch sampling in the Baltic Sea

Sampling the commercial fisheries of the Baltic Sea is one of our main tasks. For this purpose, our scientific observers regularly go to sea with fishermen to measure the catch on board. On land, we process unsorted catch samples from the fisheries to collect biological parameters like maturity and age.

More
Science onboard of German fishing vessels: Catch sampling in the Baltic Sea

Baltic Sea Fisheries: A bank for our data

During our surveys and other investigations we collect a variety of data. To save these data so that we can find and work with them, we need a database, which is not available in a shop. Therefore the Institute of Baltic Sea Fisheries, in collaboration with the two other Fisheries Institutes in the Thünen Institute, develops a database that fits our needs.

More
Baltic Sea Fisheries: A bank for our data

Recreational fishing in Germany

More
Recreational fishing in Germany

German marine angling program

Next to the commercial fishery the recreational fishery plays an important role concerning the removal of biomass from fish stocks. For certain species recreational fishery catches can have a significant share of the total landings. In addition to its importance for the scientific stock assessment recreational fishery has particular commercial relevance.

More
German marine angling program

Agent-based modelling of angler behaviour

The project contributes to a better understanding of the behaviour of recreational anglers and their responses to management decisions as precondition for sustainable recreational fisheries management.

More
Agent-based modelling of angler behaviour

Recreational fishery on salmon and sea trout

In the past, the impact of recreational fisheries (particular angling) on European marine fish stocks has often been neglected. Recent studies revealed that recreational catches can have a substantial magnitude compared to commercial catches for some European marine and diadromous fish stocks. In Germany, this seems particularly relevant for Atlantic salmon and sea trout in the Baltic Sea.

More
Recreational fishery on salmon and sea trout

Finished projects • Living marine resources

Agent-based modelling of Baltic cod

Despite extensive research in the past ICES scientist are currently not able to conclusively explain the ecological interrelationships which drive the current changes in the eastern Baltic cod stock. Equation-based macro-models do not deliver useful insights since they are not able to adequately depict the underlying physiological processes of cod. Therefore the aim of this project is the development of an agent-based multi-level model of the bioenergetics and behaviour of cod as well as of the hydrography of the Bornholm-Basin and the relevant aspects of its prey. Ultimately, the model ...

More
Agent-based modelling of Baltic cod

Population structure of cod and plaice in the Baltic Sea

In the Baltic Sea, the stocks of only two demersal fish species - cod and plaice - have so far been regulated by catch quotas. The catch quotas determine the exploitation intensity of individual fish stocks. The goal is to achieve maximum sustainable yield from a stock. If stock allocation is unclear, there is a risk of under- or over-exploitation of neighboring stocks.

More
Population structure of cod and plaice in the Baltic Sea

Otoliths make the difference

Where do you come from? What is your stock? If the fish had an identification card with information on the place of birth, this could be easily answered. Unfortunately, we have to apply significant effort to draw this secret from the fish – using their ear stones.

More
Otoliths make the difference

Tagging Baltic Sea cod (TABACOD)

How old is a fish, and how fast does it grow? These simple questions are almost impossible to answer for eastern Baltic cod, with massive consequences for fisheries management. A large-scale international tagging project may be the key to solving this problem.

More
Tagging Baltic Sea cod (TABACOD)

Catch and release mortality of eel

European eel is an important target species for european anglers. Catch restictions and minimum landing sizes lead to high releases of recreational caught eel.

More
Catch and release mortality of eel

Mortality of cod released by anglers in the Baltic Sea

Previous investigations showed that a significant number of cod caught by anglers has not reached the minimum landing size of 38 centimeters and have to be released. About 45 to 70 % of all individuals caught from boats and charter vessels are undersized.

More
Mortality of cod released by anglers in the Baltic Sea

Characterization of the recreational passive gear eel fishery

In order to improve the assessment of the European Eel it is necessary to quantify recreational catches in the North and Baltic Sea.

More
Characterization of the recreational passive gear eel fishery

Scroll to top