On Tuesday, June 7, Joacim Näslund from the University of Gothenburg, will give a seminar titled ”The pace of life of brown trout: linking growth and survival with animal personality”.

In the abstract for the seminar, Joacim writes: “The Pace-of-Life syndrome (POLS) hypothesis suggests that different individuals within a species have different combinations of physiological, behavioural and life-history traits, which are linked together. Typically, researchers have classified individuals into a few, typically two, major categories:  proactive (or bold) and reactive (or shy). Following the POLS proactive individuals are for instance more active and bold to support a faster metabolism and a higher growth rate, they have a lower stress response, and they typically have a higher risk of mortality. The reactive individuals have the opposite traits. In the seminar, I will discuss the POLS hypothesis in the light of several recent experiments on wild brown trout. I will show that the POLS is not as straight forward and intuitive as presented in conceptual papers on the topic. For instance, while several traits are linked together in a syndrome in the brown trout, the predictions from POLS are not confirmed by empirical data. As an example, during the early juvenile stage more active fish tend to have a higher probability of survival, despite a higher presumed exposure to predators and competitors. A potential explanation, relating to the behavioural ecology of the juvenile brown trout will be presented. Furthermore, I will show that the probability for survival for different POLS categories of trout likely changes during their ontogeny.”

The seminar will be given at 13:30 in room 5F416 on Karlstad University. Everyone is welcome to attend!

Last Friday, Joacim Näslund, Gothenburg University defended his thesis: “The Pace of Life of Juvenile Brown Trout – Inter- and Intra-individual Variation in Growth and Behaviour“. Opponent was Robert McLaughlin from University of Guelph, Canada. John Piccolo, from Karlstads Universiy was part of the “betygsnämnd” (evaluation committee) together with Petronella Kettunen, GU och Fredrik Nordwall, HaV. 

In relation to the defense, a workshop on “Ecology of Stream Salmonids” was organized. At the workshop, John Piccolo presented an overview of foraging and habitat selection models for salmonid restoration.

BBC har i “How do you entertain a fish?” skrivit en intressant och populär artikel om inlärning, beteende och betydelsen av komplexa miljöer hos fisk. Avstamp tas i forskning om lax i odling, om skillnaden mellan naturliga uppväxtplatser – med stenar, växter, varierade strömmar, predatorer osv. – och odlingens torftiga bassänger. Och om det är möjligt att öka överlevnaden av utsatt fisk genom att låta dem växa upp i en mer komplex miljö, till exempel med fysiska strukturer eller variationer av vattennivån. Bland forskarna som intervjuas förekommer vår NoWPaS kollega Joacim Näslund från Göteborgs Universitet.

När ändå lax och GU står i blickfånget kan vi också glädjas åt att en världsledande laxforskare är KSLA:s första Wallenberg-professor. Det är Ian Fleming som “kommer att knytas till Göteborgs universitet för att där tillföra ny kompetens för att stärka verksamheten inom fiske och vattenbruk”.