Algae blooms, which can be caused by eutrophication (increased levels of nutrients in the water, e.g. due to runoff of fertilizers and sewage into aquatic systems), drastically influence the ecology and behaviour of aquatic organisms. Effects on mate choice and the interaction of predators and prey have been observed.  Social behaviour changes are less well understood.  Stefan Fischer and Joachim Frommen from the Konrad Lorenz Institute of Ethology investigated the impacts of algae blooms on the well-known preference of three-spined sticklebacks (Gasterosteus aculeatus) to shoal with larger groups of sticklebacks when given a choice.  They showed that focal fish that could choose between two shoals of different sizes chose to spend significantly more time near the larger shoal when the water was clear, but in turbid water containing green algae the fish showed no significant preferences and tended to move less between shoals.  Eutrophication-induced algae blooms may have the potential to alter social decisions of sticklebacks, and this behaviour change might influence entire populations and even lead to changes in the structure of the social system.  The results are published in the journal Behavioral Ecology and Sociobiology.

To the article [Link 1]

(Web editor 22 May 2013)

Many species pair for life, or so the story goes. In reality, there is quite a bit of cheating going on. Both male and female partners may have “affairs” outside the pair bond.  In such cases, how is a male to know if the chicks he´s feeding are really his? Depending on the species, males have different strategies. They may try to ensure paternity by increased surveillance and fighting off the competition, or by having more frequent sex with their long-term partners. Others react by physically punishing unfaithful females or by reducing parental care once the – potentially unrelated – offspring has arrived. Herbert Hoi and colleagues of the University of Veterinary Medicine, Vienna, together with scientists from the Slovak Academy of Sciences, Bratislava, carried out experiments with reed warblers to see how a situation of potential infidelity affects later paternal investment in the chicks and whether it does in fact lead to extra-pair mating.  They found that the males aggressively try to chase off competitors and to keep potentially “double-dealing” females in line. But whether or not they manage, they turn out to be caring fathers once the babies are born. 

More info [Link 2]

(Web editor 16 May 2013)

The open access publisher BioMed Central has awarded the second prize in the category Animal Science, Veterinary Research and Zoology of the BioMed Central Annual Research Awards to Katharina Mahr, Matteo Griggio, Michaela Granatiero und Herbert Hoi for their paper „Female attractiveness affects paternal investment: experimental evidence for male differential allocation in blue tits”.

More info (in German) [Link 3]

(Web editor 10 Apr. 2013)

Model calculations predict a sea level rise of about one meter by the end of this century and of up to five and a half meters by the year 2500.  Until now there are few studies on the potential impacts of a rising sea level on biodiversity.  Florian Wetzel and colleagues of the University of Veterinary Medicine, Vienna together with Walter Jetz of Yale University, USA have now published modeling results for the Southeast Asia and Pacific regions.  Their results show that many terrestrial vertebrates are vulnerable to sea level rise and the risk of extinction is highest for endemics found only on certain islands and already endangered species.  Their findings are published online in the journal “Global Change Biology”.

More info [Link 4]

(Web editor 19 March 2013)

For a variety of reasons, many humans choose to adopt children.  More surprisingly, adoption is fairly widespread in the animal kingdom, even though it would seem to counteract the basic premise of Darwin’s theory of evolution, which suggests that animals should raise as many of their own offspring as possible.  Understanding the rationale for adoption has challenged theorists for generations.  Franziska Schaedelin and colleagues at the University of Veterinary Medicine, Vienna now describe a new approach to the problem.  The scientists present findings that suggest parents of fish exchange young with other parents to reduce the chances that their entire brood will be predated.  The results are published in the current issue of the journal “Behavioral Ecology”.

More info [Link 5]

(Web editor 19 Mar. 2013)

The zebrafish (Danio rerio) is increasingly becoming an important model species for studies on the genetic and neural mechanisms controlling behaviour and cognition.  Sarah Zala and Ilmari Määtänen of the Konrad Lorenz Institute of Ethology of the University of Veterinary Medicine Vienna tested whether social interactions with trained peers (“conditioned demonstrators“) enhance the ability of “naïve“ (unconditioned) zebrafish individuals to learn an associative foraging task. They found that the untrained zebrafish were able to improve their foraging behaviour by learning from their conditioned tank mates.  This means that zebrafish use social learning for finding food. The research is described in the January 2013 edition of the international journal “Naturwissenschaften”.

To the article [Link 6]

(Web editor 28 Jan. 2013)