Job: Project assistant

Posted by Karl Filipsson | Jobs

A thick-shelled river mussel (Unio crassus).

NRRV is looking for a part-time project assistant to work with the endangered thick-shelled river mussel (Unio crassus). The project concerns rearing of juvenile mussels in the mussel lab in Veberöd, Skåne, and reintroduction of mussels in streams in southern Sweden. Read more and apply for the position here (Swedish). The last day to apply is 2 March 2018.

Although most fieldwork is carried out in warmer seasons, members of the NRRV research group also go out in winter to collect information and samples for their research. Here, Richard Durtsche, visiting professor from Northern Kentucky University, writes about a field excursion that took place last week:

Andrew Harbicht, Post-Doc at Karlstad University (front) and Richard Durtsche, visiting professor from Northern Kentucky University, (back) at the field site.

“As part of a study on the energetics in natural food sources available to Salmonid fishes (trout, salmon, grayling, etc.), we have been sampling the macroinvertebrates in streams that connect to the Klarälven (Clear River) this past fall and now this winter. These investigations will focus on an increase in the accuracy of macroinvertebrate body size measurements taken with digital imaging and an increase in the accuracy of dry mass measures using an ultramicrobalance, newly acquired by Kau Biology. Energetic (caloric) content will also be determined for the different macroinvertebrate taxa. The three target macroinvertebrates groups for this study include mayflies (Ephemeroptera), caddisflies (Trichoptera), and stoneflies (Plecoptera). These are major prey items for all life history stages of Salmonid fishes, and are often used as indicators of stream health in aquatic environmental assessment due to their sensitivity to pollutants and anthropogenic impacts. Results of this study will be useful in developing energetic models of fish foraging for management of fish population and river/stream conditions.

The team that braved the cold winter conditions and moderate snow levels on January 29th included: Richard Durtsche (NRRV visiting professor from Northern Kentucky University), Rachel Bowes (NRRV Post-Doc), Andrew Harbicht (NRRV Post-Doc), and Rachel Prokopius (exchange student from Northern Kentucky University). The stream that we were investigating was located just south of Ransäter. The water was flowing rapidly, and we initially decided to check out the stream conditions on the downhill (east) side of highway 62 to look for sampling sites. There was knee deep (or more) snow to ford before coming to forest cover where moving was easier despite many treefalls. As the streamflow was fast and the water level high, there were no safe locations to sample. So we headed west of highway 62, just off the access road. There we found good sampling habitat just downstream of a large pool that ran under a bridge on that road.

Rachel Prokopius, exchange student from Northern Kentucky University, and Richard Durtsche, measuring the stream width and flow rates.

One of the first things we did at waterside, was to collect physicochemical measures of the water conditions. These included: temperature, pH, conductivity, and dissolved oxygen. We also measured the flow volume of water by measuring the width of the stream, and then taking the depth and flow rates every 50 cm across the stream. Water temps of 1.4°C and the tingle of cold penetrating our waders told us that today was not a good day to fall in the water. After we crossed the fast-flowing stream, we found several relatively shallow areas where we could sample invertebrates. We made a series of kick seine samples from different parts of the stream shallows to dislodge and collect invertebrates from the stones and substrate. 

It was definitely a group effort to kick stones and stream bottom, brush rocks to knock off invertebrates to be carried with stream flow into the seine, and then wash the samples into a collecting bucket. While we thought we might have limited luck, we in fact did extremely well with collecting a range of macroinvertebrates and large quantities of many of those taxa. There will be a good share of macroinvertebrate sorting and measuring upon return to the laboratory.”

Rachel Prokopius, Rachel Bowes, Post-Doc at Karlstad University, and Andrew Harbicht sampling invertebrates using a kick seine.

 

The team at work in the stream.

 

Richard Durtsche at the field site.

 

Close-up photo of a stonefly (Plecoptera) larva.

 

Book: Biology and Ecology of Pike

Posted by Karl Filipsson | Book

The book Biology and Ecology of Pike, edited by Christian Skov (Technical University of Denmark) and Anders Nilsson (Karlstad and Lund Universities) was recently published by CRC Press. The two editors have also authored several chapters in the book. The book is described to “emphasize the progress of pike research during the past two decades, highlight human dimension aspects in recreational fisheries, and to address environmental circumstances on pike populations including the pike individuals.” Read more about the book here.

 

Marcell Szabo-Meszaros, Christy Ushanth Navaratnam, Jochen Aberle, Knut Alfredsen (Norwegian University of Science and Technology), Ana T. Silva, Torbjørn Forseth (Norwegian Institute for Nature Research), Olle Calles (Karlstad University) and Hans-Petter Fjeldstad (SINTEF Energy Research) recently published the scientific paper ”Experimental hydraulics on fish-friendly trash-racks: an ecological approach” in the journal Ecological Engineering. The study is part of the project SafePass, where methods for safe and efficient migration for salmonids and European eel past hydropower structures are evaluated. SafePass aims to facilitate fish migration in regulated rivers, using perspectives of both the fish and the hydropower industry. Read more about SafePass here.

In the abstract of the paper, the authors write: ”The obstruction of fish migratory routes by hydroelectric facilities is worldwide one of the major threats to freshwater fishes. During downstream migration, fish may be injured or killed on the trash-racks or in the hydropower turbines. Fish-friendly trash-racks that combine both ecological and technical requirements are a solution to mitigate fish mortality at a low operational cost. This study presents results from an experimental investigation of head-losses and the hydrodynamic performance of six angled trash-rack types with 15 mm bar spacing, varying bar-setup (vertical-streamwise, vertical-angled and horizontal bars) and bar profiles (rectangular and drop shape) under steady flow conditions. The trash-racks were positioned at 30° to the wall of the flume and combined with a bypass at their downstream end. The impact of the different trash-rack types on the upstream flow field was characterized using Image based Volumetric 3-component Velocimetry (V3V) and at the bypass-entrance using an Acoustic Doppler Velocimeter (ADV). The results show that trash-racks with vertical streamwise and horizontal oriented bars with drop-shape profiles have similar head-losses (13% difference), while trash-racks with vertical-angled bars provide 3–8 times larger head-losses compared to the remaining configurations. The velocity measurements showed that the highest flow velocities occurred for configurations with vertical-angled bars (0.67ms−1 and 0.81ms−1 on average, respectively).Turbulence related parameters (e.g. Reynolds shear stresses and Turbulent kinetic energy) were also investigated to evaluate the performance of the alternative trash-racks from both, engineering and ecological perspectives.”

Access the paper here, or e-mail any of the authors.

The Volumetric 3-component Velocimetry (V3V) system used in the study.

For the first Tuesday seminar of the year, Kristine Lund Bjørnås, PhD-student at Karlstad University, will talk about evidence synthesis in environmental science. The seminar will be held Tuesday 23 January at 13:15 in room 5F416 at Karlstad University. Everyone is welcome to attend the seminar.

In preparation for the seminar, Kristine writes:

”In these times of alternative facts and post truth, the role and authority of scientists in society is challenged. It is therefore important that we as scientists continue to improve our methods and communication – and one way of doing that is to increase interaction with the end-users of scientific findings. In environmental- and natural resource management, many important policy and practice decisions are not being taken based on the best available scientific evidence, even when that is an explicit management objective. For instance, in a questionnaire among conservation practitioners in England, the majority (77%) reported that they used “commonsense”, “personal experience” or “speaking to other managers” as their primary source of information prior to management actions (Sutherland et al. 2004). This might be because there is no clear understanding of what the best available scientific evidence (i.e. “what works”) is. As a response to this need for more evidence-based environmental management, systematic reviews have found their way also into environmental science.

Brown trout (Salmo trutta), the model species of Kristine’s dissertation project, in an aquarium at Karlstad University.

In this seminar I will go through the principles of systematic reviewing literature, the strengths and weaknesses of the method, and I will talk about my current review project.”

References:

Sutherland, W.J.; Pullin, A.; Dolman, P.M. & Knight, T.M. 2004. The need for evidence-based conservation. TRENDS Ecol Evol. 19.6.

See also:

Mistra Council for Evidence-based Environmental management

Collaboration for Environmental Evidence

Larry Greenberg at the Lake Champlain research conference.

The Lake Champlain research conference Lake Champlain: Our future is now was held at the Davis Center, University of Vermont, in Burlington 8-9 January 2018. The conference covered a variety of topics, including climate change and native fish restoration. Larry Greenberg, professor at Karlstad University, was invited as keynote speaker at the conference and gave the talk “Conservation of landlocked Atlantic salmon in a regulated river: Taking a holistic approach.” Read more about the conference here.

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).