The human dissemination of alien species is regarded as one of the greatest threats to maintaining biodiversity.
The round goby was probably brought to the Baltic from the Black Sea via the ballast water of huge freighters, which is one of the most common ways for alien water-dwelling organisms to spread in global terms.
Gustaf Almqvist at the Department of Systems Ecology, Stockholm University, has been studying the progress of these fish in the Gulf of Gdansk for the past five years. He reports that the fish are so common there that when you wade into shallow water you can see them jumping and splashing around your feet.
"Since the species is an entirely new ingredient in the fauna of the Baltic, this is a golden opportunity to study, on the one hand, how it is adapting and, on the other hand, how it is affecting typical Baltic species," says Gustaf Almqvist.
His research shows that the species evinces differences in sexual maturity, growth, and longevity under different conditions, which probably facilitates its adaptation to strictly separate environments.
Together with Swedish and Polish colleagues, Gustaf Almqvist has shown how the new species has the potential to compete with domestic fishes, like the flounder. Even though the fish seldom grows to be more than 20 cm long, it is relatively large in comparison with related domestic fishes (sand goby, common goby, black goby). It is aggressive and territorial (the males guard the young) and therefore forces out other bottom-dwelling fishes from major coastal areas.
The two most common predatory fish in the southern Baltic, the cod and the perch, have started to exploit the new species as prey, and in coastal areas the round goby is at the top of their menu.
Mussels, above all blue mussels, are important food for round gobies, and since other fish species in the southern Baltic do not eat blue mussels to any great extent, the round goby constitutes a new link between mussels and predatory fish.
"More energy, but also more poisons, that can aggregate in mussels can therefore be transported from mussels higher up the food chain," says Gustaf Almqvist.
Everything indicates that the future spread of the species within the Baltic will be dependent on the climate, since it needs long warm summers to establish stocks.
"It's difficult to predict the future spread of the species in the Baltic, but considering changes in climate and the fact that there is no shortage of blue mussels in the Baltic, I find it hard to believe that it will not spread further," says Gustaf Almqvist.
Gustaf Almqvist wrote his dissertation in the interdisciplinary research project AquAliens (funded by the Swedish Environmental Protection Agency) and has been employed by the Coastal Laboratory of the Swedish Board of Fisheries in Öregrund and by the Department of Systems Ecology, Stockholm University.
Title of dissertation: Round goby Neogobius melanostomus in the Baltic Sea - Invasion Biology in practice.
Further information: Gustaf Almqvist, Department of Systems Ecology, Stockholm University,phone: +46 (0)8-16 10 59; cell phone: +46 (0)739-4000 92; e-mail: email@example.com.
Pressofficer Maria Sandqvist; +46-8 16 13 77, mobile +46-70664 22 64; e-mail: firstname.lastname@example.org
Preservation of floodplains is flood protection
27.09.2017 | Technische Universität München
Conservationists are sounding the alarm: parrots much more threatened than assumed
15.09.2017 | Justus-Liebig-Universität Gießen
Salmonellae are dangerous pathogens that enter the body via contaminated food and can cause severe infections. But these bacteria are also known to target...
University of Maryland researchers contribute to historic detection of gravitational waves and light created by event
On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...
Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.
Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....
Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).
When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...
Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.
How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...
23.10.2017 | Event News
17.10.2017 | Event News
10.10.2017 | Event News
23.10.2017 | Life Sciences
23.10.2017 | Physics and Astronomy
23.10.2017 | Health and Medicine