FRESHWATER NEWS
Leibniz Institute of Freshwater Ecology and Inland Fisheries (IGB)
Research for the future of our freshwaters – that is IGB’s guiding principle!
November 2023
Contagious behaviour in humans and animals ~ Small creatures, big impact ~ Assessing the risks of micro- and nanoplastics ~ Alien predators threaten birds on islands ~ Invasive species from pet trade ~ Gaming with aliens ~ GEO Emerging Leader Award for IGB researcher ~ Climate change reverses restoration successes
Hello!
Animal behavioural #research is fascinating, not least because it can reveal information about how we humans interact with each other as social beings. Behavioural biologists at IGB are deeply involved in exploring the ways in which communities, such as schools of #fish, make decisions and the factors that influence individuality. Current research shows that #behaviour can be "contagious". It also reveals the role that anticipation plays in collective decision-making – and that even genetically identical individuals raised under the same conditions can develop different character traits.
Microorganisms
Moving on from fish and humans to some of our smallest, but no less exciting, creatures. Without #microorganisms, our #ecosystems would not function properly: aquatic fungi "predigest" food, parasites keep #cyanobacteria (blue-green algae) in check, and water fleas play an important role in aquatic food web dynamics and structure. At IGB, many researchers are working on different microorganisms, studying both the #ecology of these organisms and the extent to which they are threatened by #ClimateChange and other human-induced changes. While the findings are fascinating, they are also a reminder that the diversity of life in our waters is under threat – even the microbes.
Micro- and nanoplastics
Pollution from micro- and #nanoplastics is one such threat to aquatic organisms. Researchers have investigated the #toxicity of these materials using a species of water flea (Daphnia longispina) that is common in #lakes in the Northern Hemisphere. And it turns out that this species is much more sensitive to small microplastic particles than previously thought. Tiny particles, just 50 nanometres across, of the common plastic #polystyrene were as dangerous to them as highly toxic chemicals, which are required by international and EU law to be classified and labelled. One reason for the underestimation of the risk is that toxicity has previously been assessed using the species Daphnia magna, which is less prevalent in Europe.
Assessing the environmental risk of micro- and nanoplastics is also difficult because, unlike for most other #pollutants, there are no standardised methods. IGB researchers were involved in developing a new method to assess the toxicity of these materials in soil and aquatic ecosystems in a standardised way. The new method also considers the differences between #microplastics and nanoplastics. It could contribute to a better understanding of the relationship between dose and response, or to the development of safer plastics.
Invasive species
Dangerous predators
Invasive #species can also have a major impact on ecosystems and animal populations. They can be particularly damaging to island #bird species. A prominent example is the New Zealand kiwi, whose population has been severely reduced by ferrets and other invasive predators. However, the phenomenon can also be observed in other countries, such as #Iceland, where a team of researchers led by the University of Iceland (Háskóli íslands) ’s Research Centre Sn?fellsnes and IGB used #CitizenScience data from more than a century to show that the American mink has decimated the native eider duck by about 60 per cent. And yet eider ducks – unlike the New Zealand kiwi – are quite accustomed to predatory mammals. The return of the Arctic fox, for example, had no discernible impact on the eider duck population size – presumably due to their common evolutionary history. This enabled the eider duck to develop appropriate defence strategies against the fox which, unlike the mink, cannot swim and is therefore unable to reach the birds’ nests.
Problematic #pet trade
In another study on invasive species, IGB researchers analysed which alien freshwater species are traded in Germany and the potential risks associated with the release of exotic #fish, #molluscs, #crustaceans and #amphibians. Species such as the Grass Carp (Ctenopharyngodon idella), the Neon Blue Guppy (Poecilia reticulata) and the Red-Rimmed Melania (Melanoides tuberculata) cause problems in the wild, for example by crowding out native species, carrying disease or clouding the water. Non-native species, which find suitable niches in Germany and are also cheap and readily available, proved particularly problematic. The researchers also found that the species on sale in shops and online are rarely correctly named. As a result, it is often the case that neither the buyer nor the seller knows what species is being traded. The researchers criticise that this makes regulation more difficult.
领英推荐
Gaming with aliens
A game, developed by researchers from IGB and Freie Universit?t Berlin , demonstrates that solutions for dealing with invasive species are not that simple. The game is based on future scenarios on a global and European level. Players take on the positions of different interest groups and receive their main arguments in the form of cards. The game was presented at the #SpielEssen fair in October.
Earth observations
"I never wanted to be an astronaut, but I am fascinated by the unique perspective of the Earth." (Igor Ogashawara)
IGB and GEO Aquawatch researcher Igor Ogashawara ’s fascination with water began as a teenager, when he became concerned about the impact of farmed fish on water quality. Today, the Brazilian geography graduate works with #satellite data to make statements about water quality that are relevant to aspects such as drinking water abstraction, food production and ecology. At the #GEOWeek2023 Ministerial Summit in Cape Town, South Africa, he was honoured with the prestigious GEO Emerging Leader Award this week. The global GEO network brings together national governments, research organisations and businesses to support decisions for the benefit of humanity with open Earth observation data, technologies and science.
Restoration
One way to improve chemical water quality locally is through #restoration and efficient #wastewater treatment. This is what happened to the Panke, a typical small urban river that rises to the north of #Berlin and flows into the River #Spree. Once derided as the “stinking Panke”, the river has undergone a positive transformation since the 1980s thanks to the “Panke2015” project initiated by the Federal States of Berlin and Brandenburg. A team led by Technische Universit?t Berlin and IGB has now studied how the water balance and quality have changed over the past six decades: in addition to highlighting the successes achieved, the data series also show that climate change can reverse these positive developments – for example when heavy rainfall and dry periods change the #chemodynamics of the river.
Events
Today! | Berlin: At the #BerlinScienceWeek, we make the invisible visible as a single drop of water becomes a cosmos of wonder and discovery in the Microbe Cabinet on Holzmarkt 25. In collaboration with researcher and artist Francisca Rocha Gon?alves and colleagues from the University of Aveiro (Portugal), we shed light on bacteria, algae, fungi and other organisms.
11, 12, 18 and 19 November 2023 | Berlin: What is the state of our planet’s water resources? FEZ-Berlin (KJFz-L-gBmbH) is devoting two magical weekends to this question. In playful dialogues and scenes, fairy tale characters ask exciting questions about water and go on a quest with children to find the answers. At two IGB stations, visitors of all ages can learn about the flow of a river and how fish and vegetables are grown together under one roof.
All the best and stay curious,
The IGB Team
PS: Would you like to recommend our FRESHWATER NEWS to other readers? To register, readers should click here. You can also find out about the latest news from our research on our website or by following us on X at @LeibnizIGB.
The next issue of FRESHWATER NEWS will be published in January 2024.