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Nyqvist, D., Ritchey, G. & Watz, J. (2023). Dispersal movements of non-native and native terrestrial slugs in an urban environment. Invertebrate biology.
Open this publication in new window or tab >>Dispersal movements of non-native and native terrestrial slugs in an urban environment
2023 (English)In: Invertebrate biology., ISSN 1077-8306, E-ISSN 1744-7410Article in journal (Refereed) Epub ahead of print
Abstract [en]

Animal movement varies from undirected dispersal to directed migration. Movement rates may have implications for conservation and resource management, as well as pest control, and they play a key role in invasion success. In slugs, long-distance dispersal is typically passive, whereas active movement is critical for local dispersal and determines access to resources such as food and shelter. Telemetry has recently been used to study individual slug movements in the wild, whereas movement in arena tests has explored mechanisms of interspecific competition and invasiveness in slugs. Studies that relate the performance of individual slugs in arena tests to their post-release behavior in nature are lacking. We measured individual short-term movement speed of commonly occurring native and non-native slugs of the genera Arion and Limax in arena tests and tracked their post-release dispersal movements in a garden by PIT telemetry. We demonstrate clear differences in movement behavior among the species, but non-native slugs did not display higher movement rates than their native congeners. In the arena test, slugs of the genus Limax displayed a higher short-term speed than slugs of the genus Arion, whereas in the field, individuals of Limax maximus showed lower dispersal rates compared to the other slug species. Moreover, there was a positive correlation between short-term speed in the arena test and movement in the field among individuals of L. cinereoniger, indicating the possible existence of behavioral syndromes in slugs, which may link movement ecology, animal personality, and the invasion ecology of pest species.

Place, publisher, year, edition, pages
John Wiley & Sons, 2023
Keywords
Arion, dispersal, invasive, Limax, telemetry
National Category
Zoology Ecology
Research subject
Biology
Identifiers
urn:nbn:se:kau:diva-97908 (URN)10.1111/ivb.12415 (DOI)001126273400001 ()2-s2.0-85179712489 (Scopus ID)
Funder
The Royal Swedish Academy of Agriculture and Forestry (KSLA), GFS2020‐0042
Available from: 2024-01-03 Created: 2024-01-03 Last updated: 2024-01-05Bibliographically approved
Filipsson, K., Erlandsson, A., Greenberg, L., Österling, M., Watz, J. & Bergman, E. (2023). Do predator odours and warmer winters affect growth of salmonid embryos?. Ecology of Freshwater Fish (1), Article ID e12747.
Open this publication in new window or tab >>Do predator odours and warmer winters affect growth of salmonid embryos?
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2023 (English)In: Ecology of Freshwater Fish, ISSN 0906-6691, E-ISSN 1600-0633, no 1, article id e12747Article in journal (Refereed) Published
Abstract [en]

Conditions early in ontogeny can have considerable effects later on in life. Many salmonids spawn during the autumn, and temperature during subsequent embryogenesis may have far-reaching effects on life-history traits, especially when considering ongoing climate change. Even biotic conditions during embryogenesis, such as predation threat, may affect later life stages. Here, we examined how predator odours and increased temperatures affect embryonic growth and development of a fish (brown trout Salmo trutta). We found that embryos had lower body mass and greater yolk volume close to hatching when subjected to predator odours. Trout embryos incubated at temperatures representing natural winter conditions were larger than embryos incubated at higher temperatures, although the latter hatched earlier. Fry sizes at emergence did not differ between treatments, perhaps because of compensatory growth during spring. This study shows that predator presence can have similar effects on embryonic growth of salmonids as warming winters, with possible impact later in ontogeny. 

Place, publisher, year, edition, pages
John Wiley & Sons, 2023
Keywords
brown trout, climate change, development, egg incubation, predation, yolk
National Category
Ecology Zoology Fish and Aquacultural Science
Research subject
Biology
Identifiers
urn:nbn:se:kau:diva-96852 (URN)10.1111/eff.12747 (DOI)2-s2.0-85170696207 (Scopus ID)
Funder
Karlstad University
Available from: 2023-10-02 Created: 2023-10-02 Last updated: 2023-12-11Bibliographically approved
Watz, J. & von Proschwitz, T. (2023). Egg-laying habitat selection of the invasive slug Krynickillus melanocephalus Kaleniczenko, 1851 (Gastropoda: Eupulmonata: Agriolimacidae). Folia Malacologica, 31(4), 222-228
Open this publication in new window or tab >>Egg-laying habitat selection of the invasive slug Krynickillus melanocephalus Kaleniczenko, 1851 (Gastropoda: Eupulmonata: Agriolimacidae)
2023 (English)In: Folia Malacologica, ISSN 1506-7629, Vol. 31, no 4, p. 222-228Article in journal (Refereed) Published
Abstract [en]

Invasive slugs cause damage to biodiversity as well as to horticultural and agricultural crops. To develop methods to mitigate problems with recently emerging invasive species, basic ecological knowledge about them in their new environment is crucial. We investigated the egg-laying substrate preference of Krynickillus melanocephalus in a laboratory experiment in which the slugs could choose between four different substrates. Slugs were mainly observed in contact with birch leaf compost, and less so with gravel, potting soil and sphagnum moss. Almost 90% of the eggs were found buried in birch leaves, although eggs were found also in the other substrates. In addition, we tested the winter survival of the eggs by examining their susceptibility to low temperatures. Eggs subjected to freezing temperatures did not survive, and at 8 °C, 60–70% of the eggs hatched after three months (640 degree days). In areas where K. melanocephalus is present, transporting any soil, gravel or compost material could potentially contribute to spreading the species. Particularly, leaf composts may warrant attention in this areas. 

Place, publisher, year, edition, pages
Association of Polish Malacologists, 2023
Keywords
compost, eggs, habitat use, oviposition, Stylommatophora
National Category
Ecology
Research subject
Biology
Identifiers
urn:nbn:se:kau:diva-97920 (URN)10.12657/folmal.031.029 (DOI)2-s2.0-85179989627 (Scopus ID)
Funder
The Royal Swedish Academy of Agriculture and Forestry (KSLA), GFS2019-0050
Available from: 2024-01-04 Created: 2024-01-04 Last updated: 2024-01-04Bibliographically approved
Motyka, R., Calles, O., Lind, L. & Watz, J. (2023). Growth and behaviour of juvenile European eel (Anguilla anguilla) in sandy and stony bottom substrates. Ecology of Freshwater Fish, 32(3), 640-647
Open this publication in new window or tab >>Growth and behaviour of juvenile European eel (Anguilla anguilla) in sandy and stony bottom substrates
2023 (English)In: Ecology of Freshwater Fish, ISSN 0906-6691, E-ISSN 1600-0633, Vol. 32, no 3, p. 640-647Article in journal (Refereed) Published
Abstract [en]

Understanding how the physical habitat influences growth and behaviour is essential for developing effective habitat restoration programmes of threatened and endangered fish species. In our study, we compared the growth and behaviour of juvenile European eel during 13 weeks in aquaria with either sand (0.8-2 mm) or pebbles (25-40 mm) as bottom substrate. In aquaria with the pebble substrate, eel grew significantly faster than in aquaria with sand (specific growth rate 0.15 vs. 0.11% day(-1)). Moreover, growth rates varied more for individuals inhabiting aquaria with sand than in those with pebbles (coefficient of variation 1.26 vs. 0.67). Habitat-dependent growth rates may partly be explained by the observed differences in behavioural patterns. In aquaria with sand, eel left the substrate more often and moved close to the bottom or freely in water column. In aquaria with pebbles, eel remained hidden in the substrate to a high degree, also during feeding. These results may be important for prioritising connectivity- and habitat-restoring measures and for optimization of restocking programmes.

Place, publisher, year, edition, pages
John Wiley & Sons, 2023
Keywords
conservation, elver, foraging, habitat, SGR
National Category
Ecology
Research subject
Biology
Identifiers
urn:nbn:se:kau:diva-94372 (URN)10.1111/eff.12716 (DOI)000958628400001 ()2-s2.0-85151976844 (Scopus ID)
Funder
Karlstad University
Available from: 2023-04-20 Created: 2023-04-20 Last updated: 2023-12-11Bibliographically approved
Addo, L., Hajiesmaeili, M., Piccolo, J. & Watz, J. (2023). Growth and mortality of sympatric Atlantic salmon and brown trout fry in fluctuating and stable flows. Ecology of Freshwater Fish (2), 282-290
Open this publication in new window or tab >>Growth and mortality of sympatric Atlantic salmon and brown trout fry in fluctuating and stable flows
2023 (English)In: Ecology of Freshwater Fish, ISSN 0906-6691, E-ISSN 1600-0633, no 2, p. 282-290Article in journal (Refereed) Published
Abstract [en]

Sub-daily fluctuations in streamflow may have adverse effects on the biota downstream of dams in hydropeaking-regulated rivers. Although the stranding of salmonid fry is one documented effect of hydropeaking, little is known about the species-specific behavioural and subsequent growth effects of sub-daily flow fluctuations. We investigated the effects of sub-daily flow fluctuation on growth, mortality and behaviour of sympatric Atlantic salmon (Salmo salar) and brown trout (S. trutta) fry (29–34 mm) in a laboratory experiment. The fluctuating flow treatment negatively affected growth and increased mortality for trout but not for salmon. The level of aggressive behaviour was similar in the fluctuating- and stable-flow treatments. Within the fluctuating flow treatment, there was a trend that more fishes were visibly active above the substrate during low than high flow. These findings suggest that hydropeaking-induced flow fluctuations may affect fry of different salmonid species in different ways and that brown trout fry may be more vulnerable to hydropeaking effects than Atlantic salmon fry. It can therefore be important to consider the possibility of divergent reactions by different fish species under hydropeaking situations and to incorporate species-specific strategies to conserve culturally and economically relevant riverine fish species.

Place, publisher, year, edition, pages
John Wiley & Sons, 2023
Keywords
behaviour, hydropeaking, Salmo salar, Salmo trutta, survival
National Category
Biological Sciences
Research subject
Biology; Environmental Science
Identifiers
urn:nbn:se:kau:diva-92262 (URN)10.1111/eff.12685 (DOI)000871388600001 ()2-s2.0-85140384369 (Scopus ID)
Funder
Swedish Research Council Formas, 2019‐00543Knowledge Foundation, 20170129
Available from: 2022-10-25 Created: 2022-10-25 Last updated: 2023-04-13Bibliographically approved
Watz, J., Schill, J., Addo, L., Piccolo, J. & Hajiesmaeili, M. (2023). Increased Temperature and Discharge Influence Overwinter Growth and Survival of Juvenile Salmonids in a Hydropeaking River: Simulating Effects of Climate Change Using Individual-Based Modelling. Fishes, 8(6), Article ID 323.
Open this publication in new window or tab >>Increased Temperature and Discharge Influence Overwinter Growth and Survival of Juvenile Salmonids in a Hydropeaking River: Simulating Effects of Climate Change Using Individual-Based Modelling
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2023 (English)In: Fishes, E-ISSN 2410-3888, Vol. 8, no 6, article id 323Article in journal (Refereed) Published
Abstract [en]

Climate change causes warming of rivers and may increase discharge, particularly during winter. Downstream of hydropower plants, fluctuating water temperature and flow create dynamic overwintering conditions for juvenile salmonids. We used inSTREAM 7.2-SD to simulate the effects of increased temperature (+2 & DEG;C) and discharge (+10%) on the overwinter growth and mortality of one-summer- and two-summer-old Atlantic salmon and brown trout in a river with a hydropeaking flow regime in a 2 x 2 design with replicated simulations. Water temperature had a major positive relationship with growth for both species and year classes, whereas increased flow alone had no major general effect on overwinter growth. For one-summer-old trout experiencing the high temperature regime, however, increased flow resulted in reduced growth. There were no major effects from temperature and flow on the survival rate of the two-summer-old fishes. On the other hand, there were significant interaction effects for the one-summer-olds, indicating that the effect of flow depended on temperature. For one-summer-old salmon, high flow resulted in increased survival in the low temperature regime, whereas it resulted in reduced survival in high temperature. In contrast, for one-summer-old trout, high flow resulted in reduced survival in the low temperature regime and increased survival in the high temperature. Different hydropower operation alternatives may interact with warming, affecting the relative competitive abilities of stream salmonids. Ecological models that predict the effects of different environmental conditions, such as temperature and flow regimes, may offer insight into such effects when in situ experiments are not feasible.

Place, publisher, year, edition, pages
MDPI, 2023
Keywords
flow, global warming, habitat, IBM, inSTREAM, salmon, trout
National Category
Ecology
Research subject
Biology
Identifiers
urn:nbn:se:kau:diva-96103 (URN)10.3390/fishes8060323 (DOI)001017285500001 ()2-s2.0-85163648934 (Scopus ID)
Funder
Swedish Research Council Formas, 2019-00543Knowledge Foundation, 20170129
Available from: 2023-07-13 Created: 2023-07-13 Last updated: 2023-08-09Bibliographically approved
Hajiesmaeili, M., Addo, L., Watz, J., Steven F., R. & Piccolo, J. (2023). Individual-based modelling of hydropeaking effects on brown trout and Atlantic salmon in a regulated river. Rivers Research and Applications: an international journal devoted to river research and management (3), 522-537
Open this publication in new window or tab >>Individual-based modelling of hydropeaking effects on brown trout and Atlantic salmon in a regulated river
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2023 (English)In: Rivers Research and Applications: an international journal devoted to river research and management, ISSN 1535-1459, E-ISSN 1535-1467, no 3, p. 522-537Article in journal (Refereed) Published
Abstract [en]

We developed an individual-based model (IBM) to understand the effects of hydropeaking on growth, survival and distribution of age 0+ to 1+ juveniles for high-conservation value populations of native brown trout (Salmo trutta) and Atlantic salmon (S. salar) in River Gullspång, Sweden. We parameterized and applied inSTREAM (7.2-SD) and calibrated the model by comparing predicted versus observed growth under the current hydropeaking regime (n= > 1,200 model fish for 365 days). Our objective was to model growth, survival and distribution under flow scenarios with and without hydropeaking. We observed that hydropeaking generally resulted in modest (~10%) negative effects on growth and survival of both species. Survival was more affected than was growth, smaller fish more affected than larger fish.  On-peak (high) hydropeaking flows resulted in less profitable feeding conditions (less growth) and higher predation (lower survival). Thus, inSTREAM 7.2-SD appears to capture ecologically-relevant behavioral patterns under hydropeaking, e.g., habitat selection, in response to rapid flow changes. Understanding such patterns for large rivers via manipulative field studies, even if possible, would be time-consuming and costly. Our study demonstrates the potential of IBMs as powerful tools for testing research questions and assessing and prioritizing alternative management strategies in regulated rivers. 

Place, publisher, year, edition, pages
John Wiley & Sons, 2023
Keywords
growth, habitat selection, hydropeaking, individual-based modelling, inSTREAM, salmonid, survival
National Category
Ecology Environmental Sciences
Research subject
Biology
Identifiers
urn:nbn:se:kau:diva-92253 (URN)10.1002/rra.4037 (DOI)000835196200001 ()2-s2.0-85135237023 (Scopus ID)
Funder
Swedish Research Council Formas, 2019-00543Knowledge Foundation, 20170129
Available from: 2022-10-24 Created: 2022-10-24 Last updated: 2023-04-13Bibliographically approved
Erlandsson, A., Lundholm, M., Watz, J., Bergh, A., Petrova, E., Alamdari, F., . . . Tarish, F. (2023). Infiltrating immune cells in prostate cancer tissue after androgen deprivation and radiotherapy. International journal of immunopathology and pharmacology, 37, Article ID 03946320231158025.
Open this publication in new window or tab >>Infiltrating immune cells in prostate cancer tissue after androgen deprivation and radiotherapy
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2023 (English)In: International journal of immunopathology and pharmacology, ISSN 0394-6320, Vol. 37, article id 03946320231158025Article in journal (Refereed) Published
Abstract [en]

Objectives: Androgen deprivation therapy (ADT) has long been a cornerstone in treatment of advanced prostate cancer (PCa), and is known to improve the results of radiotherapy (RT) for high-risk disease. The purpose of our study was to use a multiplexed immunohistochemical (mIHC) approach to investigate the infiltration of immune cells in PCa tissue after eight weeks of ADT and/or RT with 10 Gy.

Methods: From a cohort of 48 patients divided into two treatment arms, we obtained biopsies before and after treatment and used a mIHC method with multispectral imaging to analyze the infiltration of immune cells in tumor stroma and tumor epithelium, focusing on areas with high infiltration.

Results: Tumor stroma showed a significantly higher infiltration of immune cells compared to tumor epithelium. The most prominent immune cells were CD20(+) B-lymphocytes, followed by CD68(+) macrophages, CD8(+) cytotoxic T-cells, FOXP3(+) regulatory T-cells (Tregs), and T-bet(+) Th1-cells. Neoadjuvant ADT followed by RT significantly increased the infiltration of all five immune cells. Numbers of Th1-cells and Tregs significantly increased after single treatment with ADT or RT. In addition, ADT alone increased the number of cytotoxic T-cells and RT increased the number of B-cells.

Conclusions: Neoadjuvant ADT in combination with RT results in a higher inflammatory response compared to RT or ADT alone. The mIHC method may be a useful tool for investigating infiltrating immune cells in PCa biopsies to understand how immunotherapeutic approaches can be combined with current PCa therapies.

Place, publisher, year, edition, pages
Sage Publications, 2023
Keywords
Prostate cancer, androgen deprivation therapy, radiotherapy, immune cells, multiplex IHC
National Category
Cancer and Oncology
Research subject
Biology
Identifiers
urn:nbn:se:kau:diva-94035 (URN)10.1177/03946320231158025 (DOI)000943754200001 ()36880147 (PubMedID)2-s2.0-85149697937 (Scopus ID)
Funder
Region Värmland, LIVFOU-933876, LIVFOU-941274
Available from: 2023-03-27 Created: 2023-03-27 Last updated: 2023-08-17Bibliographically approved
Filipsson, K., Bergman, E., Erlandsson, A., Greenberg, L., Österling, M. & Watz, J. (2023). Temperature during embryonic development in brown trout influences juvenile behaviour in encounters with predators. Journal of Zoology
Open this publication in new window or tab >>Temperature during embryonic development in brown trout influences juvenile behaviour in encounters with predators
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2023 (English)In: Journal of Zoology, ISSN 0952-8369, E-ISSN 1469-7998Article in journal (Refereed) Epub ahead of print
Abstract [en]

Variation in thermal conditions during embryogenesis can have far-reaching impact throughout ontogeny and may give rise to behavioural variation. Many animals, such as salmonids, exhibit behavioural trade-offs related to foraging and predator avoidance. How embryonic temperature affects these behaviours has remained unexplored. Not only abiotic conditions during embryogenesis but also biotic factors such as predator conditioning may affect fish behaviour, especially anti-predator responses. We examined how elevated temperatures and predator odours throughout embryogenesis affect the behaviour of 28-37 mm young-of-the-year brown trout (Salmo trutta) in encounters with predators, namely Atlantic salmon (Salmo salar; 20 cm) and burbot (Lota lota; 40 cm). Juvenile brown trout were more active and aggressive if they were incubated in warmer water as eggs than if they were incubated in colder water, and trout remained inactive longer when encountering predators if they were cold incubated. Brown trout were less active and aggressive when an Atlantic salmon was present than when a burbot or no predator was present. Behavioural responses did not differ between trout that had been subjected to water with versus without predator odours during embryogenesis, possibly because brown trout were not subjected to conspecific alarm cues during egg incubation. This study shows that thermal conditions during embryogenesis can influence fish behaviour early in life and thus contribute to behavioural variation, with potential effects on life history. Considering the rapid warming of northern regions, elevated embryonic temperatures may contribute substantially to variation in salmonid behaviour in the near future. Variation in environmental conditions during embryogenesis of salmonids can have far-reaching impact throughout ontogeny and may give rise to variation in anti-predator behaviour. In a laboratory experiment, we showed that elevated temperatures throughout embryogenesis increased the activity and aggression of 28-37 mm brown trout fry and reduced the time to first movement in encounters with predators (burbot and Atlantic salmon). Predator odour during embryogenesis did not affect brown trout fry behaviour.image

Place, publisher, year, edition, pages
John Wiley & Sons, 2023
Keywords
anti-predator behaviour, climate change, development, embryogenesis, incubation temperature, salmonid
National Category
Ecology
Research subject
Biology
Identifiers
urn:nbn:se:kau:diva-97834 (URN)10.1111/jzo.13135 (DOI)001118606000001 ()2-s2.0-85179367718 (Scopus ID)
Funder
Karlstad University
Available from: 2023-12-22 Created: 2023-12-22 Last updated: 2024-01-03Bibliographically approved
Filipsson, K., Åsman, V., Greenberg, L., Österling, M., Watz, J. & Bergman, E. (2023). Winter Behavior of Juvenile Brown Trout in a Changing Climate: How Do Light and Ice Cover Affect Encounters with Instream Predators?. Fishes, 8(10), Article ID 521.
Open this publication in new window or tab >>Winter Behavior of Juvenile Brown Trout in a Changing Climate: How Do Light and Ice Cover Affect Encounters with Instream Predators?
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2023 (English)In: Fishes, E-ISSN 2410-3888, Vol. 8, no 10, article id 521Article in journal (Other academic) Published
Abstract [en]

During winter, stream fishes are vulnerable to semi-aquatic predators like mammals and birds and reduce encounters by being active in darkness or under surface ice. Less is known about the behavior of fishes towards instream piscivorous fishes. Here, we examined how surface ice and light affected the anti-predator behavior of juvenile brown trout (Salmo trutta Linnaeus, 1758) in relation to piscivorous burbot (Lota lota Linnaeus, 1758) and northern pike (Esox lucius Linnaeus, 1758) at 4 degrees C in experimental flumes. Trout had lower foraging and swimming activity and spent more time sheltering when predators were present than when absent. In daylight, trout's swimming activity was not affected by predators, whereas in darkness trout were less active when predators were present. Trout consumed more drifting prey during the day when ice was present, and they positioned themselves further upstream when under ice cover, regardless of light conditions. Trout stayed closer to conspecifics under ice, but only in the presence of pike. Piscivorous fishes thus constitute an essential part of the predatory landscape of juvenile trout in winter, and thus loss of ice cover caused by climate warming will likely affect trout's interactions with predators.

Keywords
anti-predator, global changer, diel behavior, foraging, piscivores, predators
National Category
Ecology Zoology
Research subject
Biology
Identifiers
urn:nbn:se:kau:diva-88204 (URN)10.3390/fishes8100521 (DOI)001089943500001 ()2-s2.0-85175046960 (Scopus ID)
Funder
Karlstad University
Note

This paper was included as a manuscript in doctoral thesis entitled "Early life stages of brown trout - Anti-predator responses under warming winters" 2022:2

Available from: 2022-01-26 Created: 2022-01-26 Last updated: 2023-11-28Bibliographically approved
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