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On 22.08.2022, the article “Heat causes the oxygen content in water bodies to drop” appeared in the Süddeutsche Zeitung. Similar to people who want to get refreshed in cool water, the heat is also dangerous for the inhabitants of local water bodies. “When the temperature rises, two things happen in water bodies,” said Robert Arlinghaus, professor of integrative fisheries management at Humboldt University in Berlin and research group leader at the Leibniz Institute of Freshwater Ecology and Inland Fisheries. “The oxygen content in the water drops, but at the same time the oxygen requirement of cold-blooded fish increases.” Higher temperatures also increase the formation of algae and conversion processes such as the breakdown of organic substances, which also consume oxygen. As a result, heat can also be accompanied by a lack of oxygen in the water. You can find the whole article here. (Source: )

The fifth annual marEEshift Newsletter is available now and can be downloaded following the link .

The BILD article "The fish that fools the angler" published on 01.06.2022 describes the characteristics of carp. It grows large, is widespread, and is considered a feast: the carp is one of the most popular fish that is being consumed in Germany. But for anglers, the omnivore is a real challenge: "These fish immediately spit out whatever seems strange to them," reports Professor Robert Arlinghaus in the fishing BILD podcast called "Until the bite". “We documented how the species came to places where the feeding occurred. They managed to gradually eat up all the bait without the anglers noticing," says Prof Arlinghaus. In the podcast, he also comments on allegations that the carp would destroy aquatic plants over a large area. The whole article and podcast are available here. (Source: .

In the Podcast “Berlin: What city life has to do with sustainable fishing” at the Deutschlandfunk Nova on 12.05.2022, Professor Robert Arlinghaus was talking about changes that took place in the species composition in the cities' canals and rivers. According to him “ There was a time when salmon swam through the Spree and Havel, and then ascended to the spawning grounds.” During the talk, he raised a question and provided arguments on „What does city life actually mean for the ecology of water bodies, what does city life mean for the functionality of ecosystems?“. Initially, Prof. Arlinghaus gave a talk entitled „What does city life have to do with sustainable fishing?“ in front of Red Rathaus in the frame of KOSMOS-Reading in Berlin. You can find the podcast here.

During the radio podcast for the Deutschlandfunk "Almost a religion: fishing" on 11. 05.2022 Prof Dr Robert Arlinghaus gave insights about fishing. You can listen to the podcast here. (Source: )

TV report "What fishing teaches about sustainability" was shown on ARD alpha on 29.04.2022. Fishery scientist Prof Dr Robert Arlinghaus from HU Berlin explained there how fishing impacts waterbodies and fish stocks. You can find the whole video here. (Source: )

On March 16, 2022, the article "Bottom line: daredevils come into the pan" appeared in the Badische Zeitung. ... Purely in terms of evolutionary biology, it has now turned out that those who are reticent even have an advantage. At least for fish. "Daredevils end up in the pan more often," ecologist and fisheries expert Robert Arlinghaus from Berlin's Humboldt University recently told Spiegel Online. For example, a pike that swims a lot and pushes itself to the fore is more likely to be hooked by anglers than shy conspecifics. The full interview with Der Spiegel can be found here. (Source: )

"The Professor of fishery Robert Arlinghaus on individuality and friendship amongst fish, their personality, and how adaptive carp anglers can drive crazy." That is the interview title with "Der Spiegel" on 18.02.2022, where Robert Arlinghaus answered questions about the recent publication in Science journal. The study is about high-resolution telemetry and big data and how this is immensely increasing our knowledge of animal behavior and movement. Fish, for example, show movement patterns to avoid fishing. This cannot be seen without high-resolution telemetry. However, particular behavior of individual species can also be identified. There are active fish that swim around a lot and more "lazy" fish that are less active. Fishing tends to catch vibrant fish and that means selection, so fish tend to be rather timid. The full interview with Der Spiegel can be found here. (Source: )

The Spiegel article „Why daredevils end up in the pan more often”, which was published on 18 February 2022, comprises an interview with Prof Dr Robert Arlinghaus. It deals with Prof Arlinghaus’ research, which is aimed at analyzing interrelations across fish by collecting and analyzing data of fish movements by motion sensors. It was found, for instance that carp prefer to swim with selected conspecifics during summer months, but in schools during the winter. Furthermore, different movement patterns are found within species, such as more and less active (“shy”) pikes. The former are fished more often, which leads to evolutionary pressure, which may have ecological consequences like increased growth of algae. More detailed information is provided under:

On 30.11.2021 a hearing of the EP Peche Committee took place on the topic: Data Collection and Recreational Fisheries (virtual). The hearing in the European Parliament's Committee on Fisheries served as DG Mare's assessment report on the new EUMAP (EU Multi-Annual Plan – which specifies data collection in commercial and recreational fisheries) and the hearing of some expert opinions on data collection and governance in recreational fisheries. Dr. Harry V. Strehlow and Prof. Dr. Robert Arlinghaus – from the marEEshift project – were invited as experts to discuss the impact of recreational fisheries, data collection, requirements for the EU's Common Fisheries Policy (CFP), and successful governance of recreational fisheries.

A. Hurrelmann (DG Mare) spoke of the mandatory collection of annual data from recreational fisheries considering all species and the designation of multi-species surveys. It was welcomed that many European Member States collect data on the social and economic impact of recreational fisheries, but this is done voluntarily and is not planned not to be part of the EUMAP in the future. O. Portrat (President of EFTTA) called for the recognition of recreational fisheries as a separate sector in the CFP and for a pan-European survey of marine recreational fisheries to be carried out every 5 years. Dr Strehlow warned, among other things, that there is a need for a legal framework within the CFP that regulates the allocation of resources for mixed professional and recreational fisheries based on balanced societal benefits. Prof Dr Arlinghaus presented 5 steps for an idealized fisheries policy, which represents the interests of recreational fisheries and could ensure optimal management.

The entire hearing including lectures can be found under the following link:

Prof Dr Robert Arlinghaus, who was awarded the Communicator Award  for outstanding research communication by the Stifterverband and the Deutsche Forschungsgemeinschaft in 2020, gave an interview in the 90th episode of the Stifterverband’s podcast “Forschergeist” about angling. More specifically, Prof Arlinghaus is, for instance, was talking about how people are introduced to fishing, which, according to him, is influenced mainly by the family’s socialization, (but also by connection to nature, independence, the aspect of surprise, and the challenge to catch a fish). Besides, Prof Arlinghaus’ background is being discussed, as well as fishing regulations, animal and nature protection, research on fishing, and policy implications. The episode of the podcast can be accessed here.

The third annual marEEshift Newsletter is available now and can be downloaded following the link

The MDR article "Stock collapsed: Hardly any cod left in the western Baltic Sea," (translated from original) published on August 20, 2021, describes the situation of the cod stock in the western Baltic Sea. As the article progresses, Dr Rüdiger Voss is quoted in several places. Dr Voss explains research results, such as the tipping point of the cod stock, after which the stock is significantly less productive and can no longer develop back to its previous state. He also explains that the current state is "a result of overfishing combined with a changing climate"; the cod stock is sensitive to an increase of water temperature of 2 degrees Celsius. Finally, Dr Voss made two recommendations for the future: financial aid and asking vacationers to eat more flatfish (i.e., plaice and flounder) instead of cod. More detailed information provided under:

The article "Overfishing, Climate Change and Ignorance: Cod out" (translated from original), published on August 18, 2021, in the Tagesspiegel, describes the declining cod stock in the western Baltic Sea and the influence of environmental factors and overfishing on this phenomenon. Prof Dr Robert Arlinghaus is quoted as saying that "the currently extremely low number of offspring in the Baltic cod is mainly driven by the warming of the water and other environmental factors such as oxygen and salinity." He emphasizes the relevance of environmental factors compared to selective fishing in the cod population. Prof  Dr Arlinghaus rates these research results as "bad news for the fishery for western cod," and the assumption is made that the cod cannot adapt to the new environmental conditions and cannot recover. For more details please visit

Several journals (e.g., Spiegel, FAZ, Taz, Tagesschau, Bild) have published articles about the study of Prof Dr Christian Möllmann and co-authors about the situation of the cod stock in the western Baltic Sea on August 17, 2021. Following the study, the tipping point of the cod stock, which enables the population to recover, is already exceeded. To achieve this result, Prof Möllmann and his co-authors from Kiel University’s Center for Ocean and Society (CeOS) and the German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig analyzed fishery data from several decades using statistical models.

Prof Dr Möllmann has been quoted in these journal articles several times. According to him, the cod population is probably unable to recover even though the pressure developed by the fishery industry might decrease in the future. Prof Möllmann also mentions that the problem’s cause is a combination of overfishing and increased temperatures caused by climate change. These factors led to decreased fish breeding, causing the number of surviving fish eggs to be lower. Thus, one of Prof Möllmann’s co-authors, Prof Dr Robert Arlinghaus, recommends protecting big female fish because the number of hatched eggs is disproportionately higher due to their bigger mass.

More information on the topic is provided in the articles, which can be found here:!5789736/

The underrated fisherman: role, importance, and responsibility for sustainable land use and nutrition. Lecture by Prof Dr Robert Arlinghaus at the lecture series "Animal or Tofu" at the University of Göttingen, Germany on January 21, 2020. For more details please visit

Webinar: Recreational fisheries monitoring & control, DG Mare, December 4th, 2020. The webinar's motto was: "Monitoring and control of Recreational fisheries." The background to this was the ongoing reform of the control regulation. Dr Harry V. Strehlow was invited as an expert to give an opening lecture on the biological, economic, and social context of recreational fishing in Europe. This lecture was followed by further talks, particularly on an EP pilot project that developed and tested the use of an angling App, "Fishfriender," to control catches in the sea bass fishery. With this, anglers should register their daily catches, which then accumulate on a web-based platform of the EU. Other lectures revolved around data collection with various already known apps and the advantages and disadvantages of the data collected with these methods. More than 150 participants attended a webinar. Unfortunately, the impression solidified that the COM was primarily concerned about monitoring and controlling recreational fishery in Europe but less about recognizing recreational fishing as a sector per se. The practical problems involved in implementing a Europe-wide app-based collection of fishing data from around 9 million sea anglers and over 77 million fishing days were not discussed.

For more details about the webinar and to see the presentation of Dr Strehlow, please visit

On October 29, 2020, Dr Harry V. Strehlow was invited to the Baltic Sea JDP webinar for EU inspectors, EFCA. The webinar served as training for Baltic Sea inspectors from the EU border countries. Dr Harry V. Strehlow gave an introductory lecture on marine recreational fishing in the Baltic Sea, the legal framework, existing management approaches, and control requirements.

On 26.08.2020, Dr Harry V. Strehlow was invited to the 'Workshop on Western Baltic Cod Recreational Fisheries, EFCA' as an expert on marine recreational fishing. He gave an introductory lecture on marine recreational fisheries in the Baltic Sea, the legal framework, existing management approaches, and control requirements. EFCA is the European Fisheries Control Agency, which among other things, deals with the coordination of the Member States' fisheries control activities. The coordination takes place in a regional framework, the so-called Joint Deployment Plans (JDP), of which the Baltic Sea is one region.

The second annual marEEshift Newsletter is available now and can be downloaded following the link

During the radio interview at SWR2 on 12.12.2019, Dr Harry V. Strehlow shared the outcomes of the weekly surveys that were conducted with recreational anglers. Undertaken surveys included questions about the type and amount of fish that have been fished, the frequency of fishing and whether fishing restrictions are followed. Additionally, during the radio interview, Dr Harry V. Strehlow talked about the current cod stock, fishing quotas and the reactions of the anglers to such quotas. Besides that, he provided an overview of undertaken analysis for the collected data. Namely, information about the number of recreational anglers, and the total amount that was fished. Furthermore, Dr Strehlow talked about the fishing regulations in the US that are stricter compared to ones in Germany and about his own fishing experience. For more details please visit,swr2-wissen-2019-09-18-100.html

Our first annual marEEshift Newsletter is available now and can be downloaded following the link

On 02.11.2019 Prof Dr Robert Arlinghaus gave a talk for the FischFetzen podcast “Gemeinsam auf der Suche nach Erkenntnissen” („Together in search for knowledge“). In his talk Professor Arlinghaus gave an insight into the projects related to angling that are currently taking place at the IGB (Leibniz-Institute of Freshwater Ecology and Inland Fisheries) including marEEshift project. In addition, podcast covered topics of removal windows, fishing guidelines, work of fishing clubs and much more. For more details please visit

In his video interview on 14.10.2019, Dr Harry V. Strehlow reported that the cod stock is currently close to the reference value. However, the goal is to increase the stock. Besides Dr Stehlow demonstrated how the age of the cod is being defined in the laboratory. Finally, he summed up that the fishing limit could lead towards the end of recreational fishing since cod is the main target of anglers.

In the associated article of ‘Bild’ journal, Dr Harry V. Strehlow criticizes the impending introduction of a catch limit of 2 cod per day and angler by the EU Commission. From a scientific point of view, even a limitation to five or seven fishes would be reasonable. For more details please visit

In his interview with ‘Bild’ journal on 16.09.2019, Dr Harry V. Strehlow reported about the current cod stock and its development from 2016 onwards. The current situation is better if compared to 2017; however, it is still below the lower limit that is required from a biological point of view. Concerning the discussion about the introduction of fishing quotas, Dr Harry V. Strehlow suggested applying fishing quotas that are not that drastic and recommended to introduce a so-called “close seasons” instead. According to him, fishing quotas that are too high would have a deterrent effect on the angler-tourists, who make up the majority of anglers in Germany. For more details please visit

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