Stina Gustafsson presenting her thesis.

Last Friday, Stina Gustafsson successfully defended her PhD-thesis Habitat compensation in nature-like fishways – effects on benthos and fish”. Paul Giller (Cork University, Ireland) was the opponent, and Frauke Ecke (SLU, Sweden), Brendan McKie (SLU, Sweden) and Jouni Taskinen (University of Juväskylä, Finland) constituted the grading committee.

Stina Gustafssons supervisors during her PhD were Martin Österling and Olle Calles.

The thesis is available online here. Contact Stina Gustafsson for questions and additional information.

 

On Friday, 15 December, from 13:00, Stina Gustafsson will defend her PhD-thesis “Habitat compensation in nature-like fishways – effects on benthos and fish”. Paul Giller (Cork University, Ireland) will be the opponent, and Frauke Ecke (SLU, Sweden), Brendan McKie (SLU, Sweden) and Jouni Taskinen (University of Juväskylä, Finland) constitute the grading committee. The defense will take place in 1B306 (Fryxellsalen) at Karlstad University. Everyone is welcome to attend!

In the abstract to the thesis, Stina Gustafsson writes: “The construction of nature-like fishways has become an increasingly common measure to restore longitudinal connectivity in streams and rivers affected by hydroelectric development. These fishways also have the potential to function as habitat compensation measures when running waters have been degraded or lost. The habitat potential has however often been overlooked, and therefore the aim of this thesis was to examine the potential of nature-like fishways for habitat compensation, with special focus on the effect of added habitat heterogeneity. 

This thesis examines the effects of habitat diversity on the macroinvertebrate family composition and functional organization in a nature-like, biocanal-type fishway. The biocanal contained four habitat types; riffle, pool, braided channel and floodplain. The effects of habitat diversity and large woody debris on brown trout habitat choice was also investigated in the biocanal. In addition, and prior to introduction of the threatened freshwater pearl mussel into the biocanal, the suitability of different brown trout strains as hosts for the mussel was examined. 

The results show that the habitat heterogeneity in the biocanal contributed to an increased macroinvertebrate family diversity. The functional organization of the macroinvertebrate community suggests that it was a heterotrophic system and more functionally similar to the main river than to the small streams that it was created to resemble. Brown trout habitat choice studies showed that high densities of large woody debris increase the probability of fish remaining at the site of release. Testing of different brown trout strains as host for the freshwater pearl mussel revealed that both wild and hatchery-reared brown trout strains were suitable hosts. In summary, the results indicate that it is possible to create a fish passage with added value through its high habitat function and that nature-like fishways can be designed to reach multiple species restoration goals.”

The thesis is available online here.

On Thursday, 14 December 14:00, Brendan McKie, one of the members of the grading committee, will give a presentation titled:  “River restoration and biodiversity and ecosystem functioning in tributaries of the Vindel River: The importance of restoration intensity and time”. The seminar will be given in room 5F416, at Karlstad University. Everyone is welcome to attend also the seminar.

Johan Watz, Anders Nilsson and Olle Calles from Karlstads Universitet, and Jonas Elghagen from Elghagen FIskevård, recently published the scientific note “Evaluation of a novel mobile floating trap for collecting migrating juvenile eels, Anguilla anguilla, in rivers” in the journal Fisheries Management and Ecology.

In the abstract, the authors write: “To improve the situation for the threatened European eel in regulated rivers, better methods need to be developed that more efficiently collect and transport juvenile eels past dams. In this study, a novel mobile, floating eel trap is described, and the results from an evaluation of the trap in two Swedish regulated rivers are presented. The mobile trap was designed to reduce the length of the climbing distance while maximizing the width of the entrance. The mobile trap caught more juvenile eels than a stationary eel ladder, serving as control. Furthermore, the mobility of the floating trap enables adaptive placement and thus offers managers the possibility to search for the spatial optimum for trapping efficiency.” Access the paper here, or e-mail any of the authors

The mobile floating trap next to the stationary eel ladder used as control. Photo from the Watz et al. 2017.

The mobile floating trap without cover. Juvenile eels climb the short and wide ramps (black) and slide (on the small metallic shutes) towards the left (in the photo) were they are collected. Photo: from the papers supplementary material.

The trap in the tailrace of a hydropower plant in River Lagan.

A sample of juvenile eels caught in the study, here held in a 10 L bucket.

Dennis Lafage relatively recently started a postdoc within the NRRV-research group at Karlstad University. Here he briefly presents his background and what he plans to do during his postdoc:

My name is Denis Lafage. I recently started a post-doc in the NRRV group to work on aquatic/terrestrial exchanges. I started research after working 10 years in Nature Reserves and Conservation Agencies where I was specialized in terrestrial fauna monitoring and conservation (mainly birds, invertebrates, and bats), statistics, GIS and database management.

I completed my doctorate in 2014 from the Muséum National d’Histoire Naturelle de Paris (France). My PhD thesis was dealing with the impact of management practices and natural perturbations (mainly flooding) on arthropods (spiders and carabid beetles) and plants in meadows. It also included a study using remote sensing technics to map vegetation associations using satellite imagery.

I consider myself as a community ecologist with a particular focus on arthropods. In the NRRV group, I will particularly work on a meta-analysis on the landscape drivers of aquatic/terrestrial fluxes. I will mainly focus on studies using stable isotopes for diet partitioning. As I have a particular interest in what we could call ‘perturbation ecology’ I will also work on food webs after spring floods. I have also the chance to be the co-advisor of a PhD based in Norway aiming at forecasting the impact of climate change on fishing spiders repartition in Scandinavia. Finally, I will also be involved in various projects where my skills in terrestrial arthropod ecology are required.”

Read more about Denis Lafage on his blog denislafage.wordpress.com.

Denis Lafage, sampling spiders in Sweden.

Denis Lafage, in back, and a collegue, sampling vegetation in Nantes, France.

In Denis Lafage precious work, he has been counting birds (Flamingo) in Caramargue, France.

And capturing and counting bats in roosts (France).