Earlier this week Lea Schneider, PhD-student at Karlstad University, gave a presentation about her research on parasite-host ecology, local adaptation and conservation of the thick shelled river mussel. The seminar was titled: ”Local adaptation studies and conservation: parasite-host interactions between freshwater mussels and fish” and is now available online upon registration.

To access the seminar, send an e-mail to lea.schneider@kau.se.

PENNRRV (eng. River Ecology and Management Research Group) is presented in the Pan European Networks’ publication Science and Technology:

“The River Ecology and Management Research Group at Karlstad University, Sweden, develops innovative solutions to environmental problems in direct collaboration with stakeholders such as municipalities, NGOs and industry.

The River Ecology and Management Research Group, consisting of four full professors, six researchers and seven graduate students, works towards advancing the understanding of freshwater ecosystems and their surrounding landscapes. The group conducts both basic and applied ecological research in all types of fluvial environments, from small streams to large rivers. According to the United Nation’s Millennium Ecosystem Assessment, freshwaters are among the world’s most imperilled habitats, and the past 50 years have seen drastic declines in freshwater biodiversity and ecosystem services due to anthropogenic habitat alteration. Much of the group’s research focuses on understanding the effects of flow modification and habitat loss on responses by different organisms, and applying results to solve real-world, challenge-driven problems. Studies are conducted in countries across the globe, solving environmental problems in transdisciplinary settings. Our 250m2, state-of-the-art fluvial aquarium facility enables us to experimentally identify mechanistic, behavioural responses to environmental conditions. Recent large research projects focus on fish passage in regulated rivers, forest-stream interactions, fish winter ecology, and fish-mussel host-parasite interactions…”.

Read the whole article here.

Today Lea Schneider, PhD-student at Karlstad University, will give a seminar titled: “Local adaptation studies and conservation: parasite-host interactions between freshwater mussels and fish”. The seminar will be given at 13:30 in room 5F416 on Karlstad University. Everyone is welcome to attend!

Read more about the thick shelled river mussel on NRRV.se or on UCforLife.

Fisk, precis som andra organismer, läcker hela tiden DNA till det omgivande vattnet. Detta DNA, som på engelska kallas Environmental DNA (eDNA) kommer från till exempel fiskens fjäll eller slemskikt. Teknologi som använder eDNA i vattenmassan för att kartlägga fisk har utvecklats betydligt de senaste åren. Genom att samla in vatten från ett vattendrag eller en sjö och jämföra DNA-innehållet i det insamlade vattnet med nycklar för olika arter kan man redan idag med relativt stor säkerhet avgöra närvaro av fiskarter. Forskare hoppas att i framtiden även kunna bestämma tätheter och upprätthålla kontinuerlig miljöövervakning med hjälp av eDNA. Se en kort film om teknologin på Hakai Magazines hemsida:


Läs även “eDNA technology successful in detecting Chinook salmon” om hur eDNA använts för att spåra Stillhavslax.

Ice and brown trout

Posted by Daniel Nyqvist | Vinterekologi

The stream aquaria with ice cover.

The Lab and Stream, a project that “strives to bridge the gap between anglers and academics”, has written about NRRV:s lab research on winter ecoology of brown trout:

“I think that one of the reasons that people are fascinated with fish is that they are hard to observe. Fish live in a world that is difficult to visit and largely mysterious to us air breathers, even though that world might be only a few feet underneath your boat or dock. While the underwater world might seem like an alternate dimension, the under ice world is even more distant from people’s understanding. Anyone that has stood on a frozen lake has wondered what is going on underneath them, but under ice behavior is notoriously hard to study because it’s cold and dark down there.

A cool new study by researchers from Sweden and Norway has shed some light on what trout are doing under the ice. They built stream channels in the lab that had a window on one side (to observe the fish) and added ice cover to the top of the channels to simulate a frozen river environment. In each channel they added 4 brown trout and observed their feeding and swimming behaviour…”

Read the full article at labandstream.wordpress.com.

Johan Watz led the experiment described and focoused his PhD on the winter ecololgy of salmonids. Read his thesis here. Links to the papers included are available in this blog post.

HaV har börjat samla “nya rön om bästa möjliga teknik för vattenkraften från 2015 och framåt” online. Till en början ligger fokus på fiskpassage lösningarna vid Hertings kraftverk i Ätran om vilka de skriver:

“Nya fiskpassagelösningar vid Herting vattenkraftverk i Ätran har markant förbättrat passagemöjligheterna för lax, ål och havsnejonöga. De nya passagelösningarna, en stor naturlik fiskväg och ett låglutande galler, illustrerar potentialen av att ersätta gamla passagelösningar med nya, utformade enligt rekommendationer om bästa möjliga teknik.”

På sidan finns flera länkar för den vetgirige. Kolla in den på havochvatten.se.


Hertings kraftverk. Till vänster syns det snedställda gallret för nedströmsvandrande fisk medan den stora naturlika fiskvägen tar upp bildens högra del.

The scientific paper “The Migratory Behaviour and Fallback Rate of Landlocked Atlantic Salmon (Salmo salar) in a Regulated River: does Timing Matter?” by Anna Hagelin, Olle Calles, Larry Greenberg, Daniel Nyqvist and Eva Bergman was recently published in River Research and Applications. The system studied is the River Klarälven, Sweden and in the abstract the authors write:

“The behavior of early (June–July) and late (August–September) migrating, adult Atlantic salmon, in The River Klarälven, Sweden, was analyzed using radio telemetry. River Klarälven is a regulated river without functioning fishways, instead upstream migrating salmon are trapped and trucked past eight hydropower plants before released back to the river. We distinguished two parts of the spawning migration, that is, one part being the migration from the place where the fish was released to the spawning grounds. The other part was a holding phase on the spawning grounds with little or no movements before spawning. The late salmon spent less of their total time on holding, 36.2%, and more on migration, 63.8%, compared with early migrating salmon, which distributed their time rather evenly between migration, 47.5%, and holding, 52.5%. In total, early salmon used 30% more time migrating and 156% more time holding than late salmon. Some Atlantic salmon (Salmo salar) fell back over the hydropower plant after release and got excluded from spawning. The fallback rates of transported, tagged spawners were higher in the early than in the late group in both years. The fallback rate in 2012 was 42.8% of the early group and 15.1% in the late. In 2013, there were 51.7 % fallbacks in the early group and 3.4% in the late. The salmon fell back on average 9 days after being released in 2012 and 16 days in 2013. A high mean daily discharge on the day of release increased the probability of becoming a fallback”

Download the paper here. If you don’t have free access, email any of the co-authors.