A graduate student position (licentiate) in the field stream fish ecology and habitat use, is now open for applicants at Karlstad University. The position is a full time position for 2 years within the River Ecology and Management (NRRV) group at the Department of Environmental and Life Sciences. Read more about the position on kau.se.

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Tracking smolts in Huntington River, a tributary to Winooski River.

The accepted version of the scientific article ”Downstream migration and multiple dam passage by Atlantic salmon smolts” by Daniel Nyqvist (Kau), Stephen McCormick (USGS), Larry Greenberg (Kau), William Ardren (US Fish and Wildlife), Eva Bergman (Kau), Olle Calles (Kau), and Theodore Castro-Santos (USGS) is available online at North American Journal of Fisheries Management. The paper presents a study on downstream migration and dam passage of landlocked Atlantic salmon smolts in the River Winooski, a tributary to Lake Champlain.

In the abstract the authors write: ”The purpose of this study was to investigate behavior and survival of radio-tagged wild- and hatchery-reared landlocked Atlantic salmon smolts as they migrated past three hydropower dams equipped with fish bypass solutions in the Winooski River, Vermont, USA. Among hatchery-released smolts, those released early were more likely to initiate migration and did so after less delay than those released late. Once migration was initiated, however, the late-released hatchery smolts migrated at greater speeds. Throughout the river system hatchery released fish performed similarly to wild fish. Dam passage rates varied between the three dams and was highest at the dam where unusually high spill levels occurred throughout the study period. Of the 50 fish that did migrate downstream, only 10% managed to reach the lake. Migration success was low despite the presence of bypass solutions, underscoring the need for evaluations of remedial measures; simply constructing a fishway is not synonymous with providing fish passage.”

Access the paper here or contact the authors.

The new journal The Ecological Citizen aims to advance ecological knowledge, champion earth-centered action and promote ecocentrism in political debate. NRRV member John Piccolo recommends the journal as somewhere you’ll find much interesting reading about human relationships with nature. John is also a co-author of a recently published signable statement in support of ecocentric value that he urges our readers to read and consider signing. Access the statement here: Statement of Commitment to Ecocentrism. 

Also, related to the ecocentric debate, there is an ongoing survey of attitudes to conservation. Learn more and take the survey at www.futureconservation.org.

running_silver”Running Silver – Restoring Atlantic Rivers and Their Great Fish Migration” by John Waldman is a book about the history and future of anadromous fish in the Eastern United States. The books’s main characters are Atlantic salmon, alewife, blueback herring, American shad, striped bass, sea lamprey, Atlantic sturgeon, and American eel. The eel migrates from freshwater to the sea to spawn, whereas the other species typically migrate in the other direction – from feeding areas at sea to spawning areas in freshwater.

The author uses historical records, interviews, scientific literature and personal experiences to tell the story of the migrating fish. He describes the ecology and behavior of the migrating fish but also their great historical abundances, and high social and economic importance. He describes the decline of the populations of migrating fish due to dam building, habitat loss, fishing, and pollution, but also the modern day restoration efforts. The fish are put in a social context with stories about conflicts concerning dams and fish passage dating back several hundred years. Meetings with scientists and manager occur frequently in the book, contributing to the story and providing several inspiring portraits of fish ecologists.

The book is essential reading for anyone working with migrating fish and an important book for those interested in fish and our natural world. The book is a call to action for a future with healthy migrating fish populations. Read a short review here and borrow the book from a  well-stocked library.

 

Short film: The hyporheic zone

Posted by Daniel Nyqvist | Nyheter

The hyporheic zone –  the region beneath the river bottom – is home to a wide range of minute life forms and processes of high importance for the ecology of the river. Learn more in the short film Secret Life of Rivers:

John Piccolo, researcher at Karlstad University, recently published an article in Journal for Conservation of Nature about value in natureThe paper is titledIntrinsic values in nature: Objective good or simply half of an unhelpful dichotomy?”. In the abstract John Piccolo writes: ”Two generations of conservationists and philosophers have built a strong case for intrinsic values in nature; they are the basis of the normative postulates of conservation biology. I argue that the recognition of intrinsic natural value is a fundamental and non-negotiable aspect of an eco-evolutionary worldview. Recently, relational values, “preferences, principles, and virtues associated with relationships”, have been proposed as a third category of values in nature, which may help to resolve the debate between instrumental and intrinsic valuation. By depicting intrinsic values as part of an unhelpful dichotomy between anthropocentric and ecocentric values, the current assessment of relational values fails to adequately account for the modern philosophical view of intrinsic natural value. The recognition of intrinsic natural value is not merely an academic exercise, but rather a vital aspect of conservation of the biosphere; recognition of value entails the obligation to do what is right, i.e., protect the good. Any attempt to reframe the discussion about values and environmental protection through more formal recognition of relational values will need to more clearly address how relational and intrinsic values coexist and how they can jointly form the basis for nature conservation.” 

Read the full paper here.

John Piccolo recommends the short film ”Lahontan Cutthroat Trout: A prehistoric legend returns”. The film briefly discusses the restoration of cutthroat trout to Pyramid Lake and the Truckee River in Nevada, USA. This strain of cutthroat trout was assumed extinct until remnants of the population were found in streams in neighboring Pilot Peaks. This started great efforts to re-introduce the socially and culturally important fish population to the lake. Watch the film here:

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Dokumentären ”Tana älv – mellan tre länder” (”Tanaelv – den beste elva” på norska) ligger just nu uppe på SVT-play. FIlmen handlar om laxen i älven och människorna runt den. Forskare, förvaltare, husbehovsfiskare och repressentanter för turistfisket kommer till tals. Älven – och dess biflöden – är hem för en mängd lokalt anpassade laxpopulationer och fisketrycket måste minskas för att skydda hotade laxpopulationer. Detta skapar både lokala och internationella konflikter.

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Se filmen på SVT-Play eller på NRK:s hemsida.

nyqvist2016cLast Friday, I, Daniel Nyqvist, successfully defended my PhD-thesis ”Atlantic salmon in regulated rivers – Migration, dam passage, and fish behavior” at Karlstad University. Scott Hinch (University of British Columbia, Canada) was opponent and Eva Thorstad (NINA, Norway), Kim Aarestrup (DTU AQUA, Denmark) and Hans Lundqvist (Swedish University of Agriculture) constituted the grading committee (betygskommitté). The short abstract of the thesis reads:

”Hydropower dams block migration routes, thereby posing a threat to migratory fish species. Fishways and other fish passage solutions may aid fish to pass hydropower dams. A functional fish passage solution, however, must ensure safe and timely passage for a substantial portion of the migrating fish. In this thesis, I focus on downstream passage and evaluate the behavior and survival of migrating Atlantic salmon in relation to dams in systems with (1) no fish passage solutions (2) simple passage solutions (3) best available passage solutions. In addition, I studied the survival and behavior of post-spawners and hatchery-released smolts.

A large portion of the spawners survived spawning and initiated downstream migration. For hatchery-reared smolts, early release was associated with faster initiation of migration and higher survival compared to late release. Multiple dam passage resulted in high mortality, and high spill levels were linked to high survival and short delay for downstream migrating salmon. For smolts, dam passage, even with simple passage solutions, was associated with substantial delay and mortality. Rapid passage of a large portion of the migrating adult salmon was achieved using best available passage solutions.”

The frame of the thesis is available here. Already published papers included in the thesis are Post-Spawning Survival and Downstream Passage of Landlocked Atlantic Salmon (Salmo salar) in a Regulated River: Is There Potential for Repeat Spawning? (in River Research and Applications) and Migratory delay leads to reduced passage success of Atlantic salmon smolts at a hydroelectric dam (in Ecology of Freshwater Fish). For full access to the thesis, contact daniel.nyqvist@kau.se.

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Freshwater pearl mussels.

The paper ”Heavy loads of parasitic freshwater pearl mussel (Margaritifera margaritifera L.) larvae impair foraging, activity and dominance performance in juvenile brown trout (Salmo trutta L.)”  by Karl Filipsson, Tina Petersson, Johan Höjesjö, John Piccolo, Joacim Näslund, Niklas Wengström, Martin Österling was recently published in Ecology of Freshwater Fish. In the abstract the authors write:

”The life cycle of the endangered freshwater pearl mussel (Margaritifera margaritifera) includes a parasitic larval phase (glochidia) on the gills of a salmonid host. Glochidia encystment has been shown to affect both swimming ability and prey capture success of brown trout (Salmo trutta), which suggests possible fitness consequences for host fish. To further investigate the relationship between glochidia encystment and behavioural parameters in brown trout, pairs (n = 14) of wild-caught trout (infested vs. uninfested) were allowed to drift feed in large stream aquaria and foraging success, activity, agonistic behaviour and fish coloration were observed. No differences were found between infested and uninfested fish except for in coloration, where infested fish were significantly darker than uninfested fish. Glochidia load per fish varied from one to several hundred glochidia, however, and high loads had significant effects on foraging, activity and behaviour. Trout with high glochidia loads captured less prey, were less active and showed more subordinate behaviour than did fish with lower loads. Heavy glochidia loads therefore may negatively influence host fitness due to reduced competitive ability. These findings have implications not only for management of mussel populations in the streams, but also for captive breeding programmes which perhaps should avoid high infestation rates. Thus, low levels of infestation on host fish which do not affect trout behaviour but maintains mussel populations may be optimal in these cases.”

Read the paper here. If you don’t have access to the journal’s content, email any of the authors.