Olle CallesKarlstads Universitet · Faculty of Health, Science and Technology
Olle Calles
Professor
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65
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Introduction
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December 2008 - March 2010
Publications
Publications (65)
The global population of European eel (Anguilla anguilla) is rapidly declining, and migration barriers in rivers are believed to be one of several key causes. While progress has been made in the development of bypass solutions, they are often constructed based on a limited knowledge on swimming behaviour. A bypass close to the stream bed is often r...
The establishment and proliferation of non-native fish species can have a range of effects within the local ecosystem, including alteration of food webs, nutrient cycling, pathogen dynamics and predation, sometimes also resulting in changed behavior and distribution of native fish species. Knowledge about movements and activity patterns is importan...
Modeller för att simulera effekter av flöde på strömlevande fiskpopulationer är kraftfulla verktyg för att avväga miljönytta och kostnad i samband med åtgärder för att minimera vattenkraftens miljöpåverkan. Vi jämförde en korrelativ och en individbaserad fiskhabitatmodell med avseende på vilka flöden respektive modell bedömde var gynnsammast för en...
The loss of longitudinal connectivity in regulated rivers, both up- and downstream, has been detrimental for biodiversity worldwide. While progress has been made regarding upstream fish passage solutions, many questions remain unanswered regarding downstream passage alternatives. To address these knowledge gaps, we used Atlantic salmon (S. salar) s...
Known as the "king of fishes," the Atlantic salmon (Salmo salar, Salmonidae) is an iconic freshwater species whose contribution to human well-being has long been recognized , as have widespread declines in its abundance, partly due to river regulation. To understand how salmon conservation has been addressed within the ecosystem services (ES) frame...
The European eel population is critically endangered due to a multitude of human-induced factors such as habitat fragmentation, parasites, fishing, and climate change. In freshwater, downstream migrating silver eels encountering hydroelectric plants often suffer substantial delays and increased mortality from trash-rack impingement and turbine-indu...
Fish swimming performance is strongly influenced by flow hydrodynamics, but little is known about the relation between fine-scale fish movements and hydrodynamics based on in-situ investigations. In the presented study, we validated the etho-hydraulic fish swimming direction model presented in the River Mandal from Southern Norway, using similar be...
Describing and understanding the relationship between streamflow and ecological processes is a classic problem in stream ecology and river management. We applied the individual-based model inSTREAM to describe the relationship between the dynamic river habitat and emergent population responses in sympatric landlocked Atlantic salmon (Salmo salar) a...
Dams, weirs, and hydropower facilities are often cited as migratory barriers which impart significant reductions in fitness among migratory fish species. Even where upstream and downstream passage options are available, barrier passage can still often result in energetic or physical costs which compound delays or cause mortality. Past studies have...
Passage of hydropower plants by upstream-migrating salmonid spawners is associated with reduced migration success, and the need for knowledge of fish behavior downstream of dams is widely recognized. In this study, we examined fishway passage of landlocked Atlantic salmon in River Klarälven, Sweden and brown trout in River Gudbrandslågen, Norway, a...
Cost-effective implementation of fish-friendly hydropower flow operation and habitat restoration measures require an understanding of their effects on fitness-related behaviours of stream fish. Here, we investigated how changes in flow and bottom structure influence the social behaviour of European grayling, using large experimental flumes (700 L s...
The negative effects of hydroelectric power (HEP) on salmonid populations has long been recognized and studied. Downstream passage through turbines may potentially constitute a significant source of mortality for both juvenile and adult fish in regulated rivers. Numerical models have been developed to calculate turbine passage mortality based on th...
The European eel Anguilla anguilla Linnaeus 1758 is critically endangered with recruitment estimated at 5%‑10% of historical levels. Enhancing survival of recruits is pivotal for conservation, and restoration should consider habitat choice of elvers ascending river systems. We experimentally show that newly ascended elvers choose small pebble habit...
https://www.sciencedirect.com/science/article/pii/S1146609X21000709
To improve the management of the European eel (Anguilla anguilla) in freshwater, it is essential to define important lotic habitats. Electrofishing data from 289 wadeable, hard-bottom sites in 69 Swedish coastal rivers and streams, originally surveyed for salmonid monitoring, were used to evaluate the effects of sampling- and habitat-related factor...
To improve the management of the Euro-pean eel (Anguilla anguilla) in freshwater, it is essential to define important lotic habitats. Electrofish-ing data from 289 wadeable, hard-bottom sites in 69 Swedish coastal rivers and streams, originally surveyed for salmonid monitoring, were used to evaluate the effects of sampling-and habitat-related facto...
• Many diadromous fish populations are declining and at risk of collapse. Lack of river connectivity is a major contributor to these declines, as free migration routes between marine and freshwater habitats are crucial for life‐history completion. For the conservation and ultimately recovery of such species, it is imperative that remedial measures...
Where migrating fish have to pass multiple dams, very high passage performance is required at the series of obstacles to avoid accumulated negative effects of multiple dam passage. In some rivers, migrating fish are trapped, transported past several obstacles, and released to continue their migration. Such trap-and-transport solutions, however, hav...
Conservation programmes for endangered, long‐lived and migratory species often have to target multiple life stages. The bottlenecks associated with the survival of juvenile anguillid eels migrating into inland waters, the survival and growth of the freshwater life stage, as well as the recruitment and survival of silver eels, migrating back to the...
F or as long as we have been human, people have wondered about our relationship with the rest of the natural world. In particular, freshwater rivers and streams have played a pivotal role in the evolution of human culture. Indeed, our relationships with rivers can be said to be older than humanity itself-ancestral species of the genus Homo certainl...
• Habitat structural complexity affects the behaviour and physiology of individuals, and responses to the environment can be immediate or influence performance later in life through delayed effects.
• Here, we investigated how structural enrichment, both pre‐release in the hatchery rearing environment and post‐release in the wild, influenced winter...
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 fis...
Solutions for fish migrations in a river with multiple dams.
Hydropower dams disrupt longitudinal connectivity and cause fragmentation of river systems, which has led
to declines in migratory fish species. Atlantic salmon smolts rely on intact longitudinal connectivity to move downstream
from rearing habitats in freshwater to feeding grounds at sea. Smolts often suffer increased mortality and delays when the...
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...
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 migratio...
Studying fish behaviour at hydropower dams is needed to facilitate the design and improvement of fish passage solutions, but few studies have focused on Atlantic salmon kelts. Here, we used radio telemetry (n = 40, size range = 50–81 cm) and acoustic sonar to study kelt movements in the forebay as well as their dam passage survival and subsequent m...
Passage of fish through hydropower dams is associated with mortality, delay, increased energy expenditure and migratory failure for migrating fish and the need for remedial measures for both upstream and downstream migration is widely recognised. A functional fish passage must ensure safe and timely passage routes that a substantial portion of migr...
The Daugava River is the largest river in Latvia. Daugava Hydro Power Plants built in 1939 – 1974 are Latvia's most important renewable resource in generation of electricity. The absence of fish passage structures excludes upstream migration of diadromous species. Compensatory stocking activities are introduced annually. The need for studying alter...
Repeat salmonid spawners may make large contributions to total recruitment and long term population stability. Despite their potential importance, relatively little is known about this phase of the life history for anadromous populations, and nothing has been reported for landlocked populations. Here, we studied post-spawning behaviour and survival...
Surface ice in rivers and lakes buffers the thermal environment and provides overhead cover, protecting aquatic animals from terrestrial predators. We tested if surface ice influenced the behavior (swimming activity, aggressive encounters, and number of food items eaten) and stress level (coloration of eyes and body) of stream-living brown trout Sa...
Upstream migration by adult salmonids is impeded by dams in many regulated rivers, as is the case for landlocked Atlantic salmon, Salmo salar, in the River Klarälven, Sweden. There, the salmon cannot reach the spawning grounds due to the presence of eight dams. Hence, hatchery-reared smolts are released downstream of the dams, and upstream migratin...
The European eel stock has long been in decline. Consequently, the species
has been added to the IUCN Red List of Threatened Species. One threat that
has been identified as one possibly having an impact on the stock is mortality
caused by hydroelectric power plant turbines. Turbine management, which is
adapted to preferable migration conditions, mi...
Summary
In this study, 100 silver eels were tagged with radio transmitters and released upstream of two power plants; Skärblacka and Fiskeby, in the river Motala Ström in the autumn 2013. The eels' migration behavior in freshwater, route choice and impact of the power plants in terms of delayed migration and increased mortality were studied. At bot...
Preferring one social partner over another can enhance fitness. This paper reports that juvenile grayling were significantly more likely to enter and forage in new, upstream habitats when paired with familiar versus unfamiliar social partners. Fish paired with unfamiliar partners or when alone were more reluctant to enter the new area. The entry ti...
The European eel (Anguilla anguilla) is a critically endangered species, and one major threat is the survival of silver eels migrating downstream towards the sea from lake and river rearing areas. During this migration, many eels are impinged and die on intake racks, or are injured or killed when passing through turbines.Intake racks at a hydroelec...
In the context of water resources planning and management, the prediction of fish distribution related to
habitat characteristics is fundamental for the definition of environmental flows and habitat restoration measures. In particular, threatened and endemic fish species should be the targets of biodiversity safeguard and wildlife conservation acti...
This chapter provides a brief historical review of downstream bypass problems in Sweden. This is followed by a description of the Swedish situation today, with a focus on several case studies that have evaluated rehabilitating downstream bypass efficiency at hydroelectric plants in rivers of different sizes and for several different species. Finall...
European eel stocks are in steep decline, and the species’ complex catadromous life cycle, including marine and freshwater inhabitation, complicates the identification of responsible causes. Besides natural impacts like climate change and parasite infestation, several anthropogenic factors are proposed as possible explanations. Along with overfishin...
Forskargruppen Naturresurs Rinnande Vatten på ämnet biologi vid Karlstads universitet medverkar i det Interregfinansierade projektet Vänerlaxens fria gång. Under två år har vi genomfört projekt i Klarälven i syfte att lära oss mer om laxens biologi i Klarälven. För att kunna genomföra en god förvaltning av ett ekosystem måste man ha goda kunskaper...
Det europeiska ålbeståndet har minskat drastiskt under de senaste årtiondena och år 2007 antog därför EU en förordning, som innehåller åtgärder för återhämtning av beståndet av europeisk ål och som innebar att alla medlemsländer måste upprätta en nationell ålförvaltningsplan. I Sveriges ålförvaltningsplan anges minskad dödlighet i vattenkraftverk s...
Power plant dams constitute barriers for downstream migration by smolts. The purpose of this study was to measure guidance efficiency of existing trash diverters and the use of overhead cover in combination with trash diverters to guide brown trout (Salmo trutta L.) smolts away from turbine intakes into trash spillway gates at two power plants in t...
The present study aimed at defining and testing a simple and widely applicable management tool, based on already available or easily collectable data, which could allow Watershed Authorities to prioritize the interventions for river longitudinal connectivity restoration, reopening fish migration routes. The proposed priority indices for fish passes...
Intact longitudinal conductivity ensures that fish migrate between habitats. Here, we present our studies of longitudinal connectivity conducted from 2000-2009 as they relate to migration of trout and other species in the regulated River Emån, Sweden. Two nature-like fishways for upstream migration were constructed at Finsjö, approximately 30 km up...
The River Ätran is an important river for diadromous fish species on the Swedish west-coast. Wild populations of wild Atlantic salmon, trout, European eel and sea lamprey enter the river for spawning and growth. The conditions for migratory fish species are improving in the river since rehabilitation efforts now address the needs of all diadromous...
Abstract – The possibility to increase the proportion of migrating hatchery-reared smolts by reducing their food ration was studied. Lake-migrating, hatchery-reared salmon (Salmo salar) and trout (Salmo trutta) smolts were either fed normal rations, based on recommendations from the fish-farming industry, or reduced (15–20%) rations. They were rel...
Technical improvements to ameliorate downstream passage for diadromous fish have rarely been evaluated in regulated rivers in northern Europe. The current study evaluated rehabilitative measures for downstream migrating Atlantic salmon, brown trout and European eel at a hydroelectric plant in southern Sweden. Smolts (N = 66), kelts (N = 20) and sil...
1. The European eel population has decreased drastically during recent decades, and new EU-legislation calls for measures to change this negative trend. This decline has been attributed to a number of factors, including habitat fragmentation by structural barriers that prevent eels moving between freshwater and the sea. The success of downstream mi...
Russon IJ, Kemp PS, Calles O. Response of downstream migrating adult European eels (Anguilla anguilla) to bar racks under experimental conditions. Ecology of Freshwater Fish 2010: 19: 197–205. © 2010 John Wiley & Sons A/S
Abstract – The behavioural response of downstream migrating nonsalmonid fish to hydraulic conditions associated with river infra...
IntroductionMaterial and methodsResults and discussionConclusions and implications for managementAcknowledgementsReferences
Rivinoja, P., Calles, O., Thorfve, S., Lundqvist, H. & Leonardsson, K. 2010. Assessment of potential passage probabilities and reproduction areas for Atlantic salmon (Salmo salar L.) in the fragmented regulated River Ljusnan-A baseline of hypothetical scenarios for eco-eco analyses. 16 pages. The potential to recover migration routes and reproducti...
Rivinoja, P., Calles, O., Karlsson, S. and S. Lundström. 2010. Effects of small scale hydropower on aquatic fauna. 21 pages. The potential effect of small scale hydropower on aquatic fauna is reviewed, with main focus on fish. At the time when hydropower was introduced, little attention was paid to its negative impact on the environment, yet more r...
We evaluated the effects of a rehabilitation project, whose goal was to re-establish longitudinal connectivity for anadromous trout in the regulated river Emån. We used a holistic approach, by tagging and following both upstream-migrating spawners (N = 348) and downstream-migrating smolts (N = 80) and kelts as they passed two hydroelectric plants (...
Water regulation may alter hydraulic head gradients with consequences for the exchange of water between the river and the hyporheic zone. The objective of this study was to investigate the effect of discharge on hyporheic water quality in a regulated Swedish boreal river during a 10-day experimental period with a sequence of alternating high- and l...
This study describes the temporal and spatial variations in hyporheic water quality in three boreal rivers, the River Tobyälven, an unregulated river, the river Mangälven, a regulated river with a minimum discharge requirement and the river Järperudsälven, a regulated river without any minimum discharge requirements. A total of 43 permanent piezome...
Abstract – We studied the use of two nature-like fishways by 15 fish species (N = 240) in the River Emån in southern Sweden. Use of the fishways for both passage and as a habitat was studied by electrofishing, trap catches and PIT telemetry. Of the 187 PIT-tagged fish, 52 individuals from 10 different species ascended one of the fishways for a tot...
We evaluated the function of two nature-like fishways for re-establishing connectivity for anadromous salmonids in the regulated River Emån. Between 90 and 100% of the salmonids that entered the fishways actually passed through them, with median speeds of 180–190 m h−1. Only 50% of the anadromous brown trout that passed the first fishway also passe...
Projects
Projects (9)
To use turbulent eddies to create efficient, cost-effective and easier to operate guide system for fish and to develop design guidelines for the construction and implementation of such systems. The practical guideline will also explore how the knowledge on turbulence and fish can be used in mitigation of other migration challenges (e.g. upstream migration).
For more information on the project please check :
https://www.nina.no/fishpath
LIFE CONNECTS is a LIFE+ Nature project with a budget of 10 million euro. The project aims to improve ecosystem functions and ecosystem services in seven southern Swedish rivers and in the long term also the Baltic Sea . This benefits people, biodiversity and sustainable water use. The two threathened mussel species, Thick-shelled river mussel (Unio crassus) and Freshwater pearl mussel (Margaritifera margaritifera), together with the fish species Atlantic salmon (Salmo salar) and European eel (Anguilla anguilla) are target species for this unique project. If we can get these species to thrive again, the project will be a success with cleaner water and greater biodiversity as a result. Not only in the rivers where the project is being implemented but it is reasonable to assume positive effects in the Baltic Sea in the long run.
In seven streams, ecosystem features will be enhanced by creating free migration paths, passage opportunities at obstacles, and by adding a more varied bottom structure (sand, gravel, stone, blocks and dead wood), it will improve fish migration opportunities and habitats for fish and mussels for better water quality and more natural rivers.
The two mussel species, Thick-shelled river mussel and Freshwater pearl mussel, have a complex lifecycle in which the mussel as a larva lives parasitically on the gills of a host fish. The gills of the fish are both a food resource and a habitat necessary for the mussel to complete its life cycle. At present, we do not know exactly which species of fish are suitable for hosting the mussel in the various rivers, such as Atlantic salmon, Brown trout, European bullhead, and European river lamprey., Thus, within the project we will study this phenomenon by mapping fish species migration, their function as hosts – ie which fish species generate high growth and survival for the mussel larvae as well as the survival and growth of mussels that have been reintroduced into the river.
Another focus for the project are information efforts and communication. The project will constitute an engine for further water conservation projects, both nationally and internationally. The project runs during the period of 2019 to 2025.
Link to project website: https://lifeconnects.se/?lang=en
RIBES (River flow regulation, fish BEhaviour and Status) European Training Network (ETN) will train 15 ESRs in the interdisciplinary field of Ecohydraulics to find innovative solutions for freshwater fish protection and river continuity restoration in anthropogenically altered rivers.
More information: www.msca-ribes.eu