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Koch-Schmidt, Per
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Nordahl, O., Koch-Schmidt, P., Sunde, J., Yildirim, Y., Tibblin, P., Forsman, A. & Larsson, P. (2019). Genetic differentiation between and within ecotypes of pike (Esox lucius) in the Baltic Sea. Aquatic conservation
Open this publication in new window or tab >>Genetic differentiation between and within ecotypes of pike (Esox lucius) in the Baltic Sea
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2019 (English)In: Aquatic conservation, ISSN 1052-7613, E-ISSN 1099-0755Article in journal (Refereed) Epub ahead of print
Abstract [en]

Aquatic systems often lack physical boundaries for gene flow, but ecological and behavioural barriers can form surprisingly fine spatial scale genetic patterns that challenge traditional, large scale management. To detect fine spatial scale structures, understand sources of intraspecific diversity, and design appropriate management plans requires identification of reproductively isolated units. This study reports on genetic differentiation in pike (Esox lucius) within a coastal area stretching 55 km from south to north in the central Baltic Sea. Pike is here an economically and ecologically important top predator that has declined in abundance. However, population structures have mostly been studied on large spatial scales, and without considering the potential for genetic divergence between the sympatric anadromous fresh water and the resident brackish water spawning ecotypes. To this end, 487 individuals from the east coast of Sweden and the island of oland, representing sympatric anadromous and resident spawning individuals, categorized to ecotype based on spawning location or otolith microchemistry, were genotyped for 10 microsatellites and used to test for divergence between ecotypes. Furthermore, divergence between regions (island/mainland), neighbouring spawning locations (n = 13) and isolation by distance within and between regions were evaluated for the anadromous ecotype. The results revealed strong genetic differences between regions, between spawning locations separated by as little as 5 km and the first evidence of genetic differentiation between resident and anadromous ecotypes; despite a high dispersal capacity of pike and a high connectivity within the study area. The signatures of isolation by distance indicated that connectivity among populations differed between regions, probably reflecting availability of spawning habitats. To safeguard against the challenges and uncertainties associated with environmental change, adaptive conservation management should aim to promote high intra-population functional genetic diversity without compromising the continued integrity and coexistence of the different ecotypes and of locally adapted sub-populations.

Place, publisher, year, edition, pages
John Wiley & Sons, 2019
Keywords
biodiversity, brackish, climate, coastal, fish, fishing, genetics, migration, wetland
National Category
Ecology
Research subject
Ecology, Aquatic Ecology
Identifiers
urn:nbn:se:lnu:diva-88825 (URN)10.1002/aqc.3196 (DOI)000481341300001 ()
Available from: 2019-08-29 Created: 2019-08-29 Last updated: 2019-08-29
Nordahl, O., Tibblin, P., Koch-Schmidt, P., Berggren, H., Larsson, P. & Forsman, A. (2018). Sun-basking fish benefit from body temperatures that are higher than ambient water. Proceedings of the Royal Society of London. Biological Sciences, 285(1879), Article ID 20180639.
Open this publication in new window or tab >>Sun-basking fish benefit from body temperatures that are higher than ambient water
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2018 (English)In: Proceedings of the Royal Society of London. Biological Sciences, ISSN 0962-8452, E-ISSN 1471-2954, Vol. 285, no 1879, article id 20180639Article in journal (Refereed) Published
Abstract [en]

In terrestrial environments, cold-blooded animals can attain higher bodytemperatures by sun basking, and thereby potentially benefit from broaderniches, improved performance and higher fitness. The higher heat capacityand thermal conductivity of water compared with air have been universallyassumed to render heat gain from sun basking impossible for aquaticectotherms, such that their opportunities to behaviourally regulate body temperatureare largely limited to choosing warmer or colder habitats. Here wechallenge this paradigm. Using physical modelswe first showthat submergedobjects exposed to natural sunlight attain temperatures in excess of ambientwater. We next demonstrate that free-ranging carp (Cyprinus carpio) canincrease their body temperature during aquatic sun basking close to thesurface. The temperature excess gained by basking was larger in dark thanin pale individuals, increased with behavioural boldness, and was associatedwith faster growth. Overall, our results establish aquatic sun basking as a novelecologically significant mechanism for thermoregulation in fish. The discoveryof this previously overlooked process has practical implications for aquaculture,offers alternative explanations for behavioural and phenotypicadaptations, will spur future research in fish ecology, and calls for modificationsof models concerning climate change impacts on biodiversity inmarine and freshwater environments.

Place, publisher, year, edition, pages
London: Royal Society Publishing, 2018
National Category
Ecology Evolutionary Biology
Research subject
Natural Science, Ecology
Identifiers
urn:nbn:se:lnu:diva-75330 (URN)10.1098/rspb.2018.0639 (DOI)000433506100024 ()2-s2.0-85047935379 (Scopus ID)
Available from: 2018-06-07 Created: 2018-06-07 Last updated: 2019-08-29Bibliographically approved
Tinnert, J., Hellgren, O., Lindberg, J., Koch-Schmidt, P. & Forsman, A. (2016). Population genetic structure, differentiation, and diversity in Tetrix subulata pygmy grasshoppers: roles of population size and immigration. Ecology and Evolution, 6(21), 7831-7846
Open this publication in new window or tab >>Population genetic structure, differentiation, and diversity in Tetrix subulata pygmy grasshoppers: roles of population size and immigration
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2016 (English)In: Ecology and Evolution, ISSN 2045-7758, E-ISSN 2045-7758, Vol. 6, no 21, p. 7831-7846Article in journal (Refereed) Published
Abstract [en]

Genetic diversity within and among populations and species is influenced by complex demographic and evolutionary processes. Despite extensive research, there is no consensus regarding how landscape structure, spatial distribution, gene flow, and population dynamics impact genetic composition of natural populations. Here, we used amplified fragment length polymorphisms (AFLPs) to investigate effects of population size, geographic isolation, immigration, and gene flow on genetic structure, divergence, and diversity in populations of Tetrix subulata pygmy grasshoppers (Orthoptera: Tetrigidae) from 20 sampling locations in southern Sweden. Analyses of 1564 AFLP markers revealed low to moderate levels of genetic diversity (PPL=59.5-90.1; Hj=0.23-0.32) within and significant divergence among sampling localities. This suggests that evolution of functional traits in response to divergent selection is possible and that gene flow is restricted. Genetic diversity increased with population size and with increasing proportion of long-winged phenotypes (a proxy of recent immigration) across populations on the island of oland, but not on the mainland. Our data further suggested that the open water separating oland from the mainland acts as a dispersal barrier that restricts migration and leads to genetic divergence among regions. Isolation by distance was evident for short interpopulation distances on the mainland, but gradually disappeared as populations separated by longer distances were included. Results illustrate that integrating ecological and molecular data is key to identifying drivers of population genetic structure in natural populations. Our findings also underscore the importance of landscape structure and spatial sampling scheme for conclusions regarding the role of gene flow and isolation by distance.

Keywords
dispersal, evolution, gene flow, Orthoptera, polymorphism, population divergence, Tetrix subulata
National Category
Ecology Evolutionary Biology
Research subject
Ecology, Evolutionary Biology
Identifiers
urn:nbn:se:lnu:diva-59010 (URN)10.1002/ece3.2520 (DOI)000387120800024 ()2-s2.0-84990964599 (Scopus ID)
Available from: 2016-12-15 Created: 2016-12-14 Last updated: 2018-10-24Bibliographically approved
Larsson, P., Tibblin, P., Koch-Schmidt, P., Engstedt, O., Nilsson, J., Nordahl, O. & Forsman, A. (2015). Ecology, evolution, and management strategies of northern pike populations in the Baltic Sea. Ambio, 44(Supplement 3), S451-S461
Open this publication in new window or tab >>Ecology, evolution, and management strategies of northern pike populations in the Baltic Sea
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2015 (English)In: Ambio, ISSN 0044-7447, E-ISSN 1654-7209, Vol. 44, no Supplement 3, p. S451-S461Article, review/survey (Refereed) Published
Abstract [en]

Baltic Sea populations of the northern pike (Esox lucius) have declined since the 1990s, and they face additional challenges due to ongoing climate change. Pike in the Baltic Sea spawn either in coastal bays or in freshwater streams and wetlands. Pike recruited in freshwater have been found to make up about 50 % of coastal pike stocks and to show natal homing, thus limiting gene flow among closely located spawning sites. Due to natal homing, sub-populations appear to be locally adapted to their freshwater recruitment environments. Management actions should therefore not involve mixing of individuals originating from different sub-populations. We offer two suggestions complying with this advice: (i) productivity of extant freshwater spawning populations can be boosted by modifying wetlands such that they promote spawning and recruitment; and (ii) new sub-populations that spawn in brackish water can potentially be created by transferring fry and imprinting them on seemingly suitable spawning environments.

Keywords
climate change conservation, Esox lucius, habitat, Baltic Sea
National Category
Ecology
Research subject
Natural Science, Aquatic Ecology
Identifiers
urn:nbn:se:lnu:diva-43193 (URN)10.1007/s13280-015-0664-6 (DOI)000362290800012 ()2-s2.0-84937573371 (Scopus ID)
Projects
EcochangeStiftelsen Olle Engqvist Byggmästare
Funder
Ecosystem dynamics in the Baltic Sea in a changing climate perspective - ECOCHANGE
Available from: 2015-05-12 Created: 2015-05-12 Last updated: 2017-12-04Bibliographically approved
Tibblin, P., Forsman, A., Koch-Schmidt, P., Nordahl, O., Johannessen, P., Nilsson, J. & Larsson, P. (2015). Evolutionary divergence of adult body size and juvenile growth in sympatric subpopulations of a top predator in aquatic ecosystems. American Naturalist, 186(1), 98-110
Open this publication in new window or tab >>Evolutionary divergence of adult body size and juvenile growth in sympatric subpopulations of a top predator in aquatic ecosystems
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2015 (English)In: American Naturalist, ISSN 0003-0147, E-ISSN 1537-5323, Vol. 186, no 1, p. 98-110Article in journal (Refereed) Published
Abstract [en]

Evolutionary theory predicts that different selective regimes may contribute to divergent evolution of body size and growth rate among populations, but most studies have focused on allopatric populations. Here, we studied five sympatric subpopulations of anadromous northern pike (Esox lucius) in the Baltic Sea subjected to allopatric habitats for a short period of their life cycle due to homing behavior. We report differences in adult body size among subpopulations that were in part due to variation in growth rate. Body size of emigrating juveniles also differed among subpopulations, and differences remained when individuals were reared in a common environment, thus indicating evolutionary divergence among subpopulations. Furthermore, a QST-FST comparison indicated that differences had evolved due to divergent selection rather than genetic drift, possibly in response to differences in selective mortality among spawning habitats during the allopatric life stage. Adult and juvenile size were negatively correlated across subpopulations, and reconstruction of growth trajectories of adult fishes suggested that body size differences developed gradually and became accentuated throughout the first years of life. These results represent rare evidence that sympatric subpopulations can evolve differences in key life-history traits despite being subjected to allopatric habitats during only a very short fraction of their life.

National Category
Evolutionary Biology
Research subject
Ecology, Evolutionary Biology
Identifiers
urn:nbn:se:lnu:diva-43212 (URN)10.1086/681597 (DOI)000356632700011 ()26098342 (PubMedID)2-s2.0-84933575222 (Scopus ID)
Projects
EcoChange
Available from: 2015-05-13 Created: 2015-05-13 Last updated: 2018-05-16Bibliographically approved
Forsman, A., Tibblin, P., Berggren, H., Nordahl, O., Koch-Schmidt, P. & Larsson, P. (2015). Pike Esox lucius as an emerging model organism for studies in ecology and evolutionary biology: a review.. Journal of Fish Biology, 87(2), 472-479
Open this publication in new window or tab >>Pike Esox lucius as an emerging model organism for studies in ecology and evolutionary biology: a review.
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2015 (English)In: Journal of Fish Biology, ISSN 0022-1112, E-ISSN 1095-8649, Vol. 87, no 2, p. 472-479Article, review/survey (Refereed) Published
Abstract [en]

The pikeEsox luciusis a large, long-lived, iteroparous, top- predator fish species with a circumpolardistribution that occupies a broad range of aquatic environments. This study reports on a literaturesearch and demonstrates that the publication rate ofE. luciusresearch increases both in absolute termsand relative to total scientific output, and that the focus of investigation has changed over time frombeing dominated by studies on physiology and disease to being gradually replaced by studies on ecol-ogy and evolution.Esox luciuscan be exploited as a model in future research for identifying causes andconsequences of phenotypic and genetic variation at the levels of individuals, populations and speciesas well as for investigating community processes.

National Category
Ecology
Research subject
Ecology, Evolutionary Biology
Identifiers
urn:nbn:se:lnu:diva-43210 (URN)10.1111/jfb.12712 (DOI)000359421400017 ()26077107 (PubMedID)2-s2.0-84938746772 (Scopus ID)
Projects
EcoChange
Available from: 2015-05-13 Created: 2015-05-13 Last updated: 2018-05-16Bibliographically approved
Tibblin, P., Koch-Schmidt, P., Larsson, P. & Stenroth, P. (2012). Effects of salinity on growth and mortality of migratory and resident forms of Eurasian perch in the Baltic Sea. Ecology of Freshwater Fish, 21(2), 200-206
Open this publication in new window or tab >>Effects of salinity on growth and mortality of migratory and resident forms of Eurasian perch in the Baltic Sea
2012 (English)In: Ecology of Freshwater Fish, ISSN 0906-6691, E-ISSN 1600-0633, Vol. 21, no 2, p. 200-206Article in journal (Refereed) Published
Abstract [en]

In the coastal areas of the Baltic Sea, there are two forms of perch (Perca fluviatilis). One of the forms is migratory and spawns instreams entering the Baltic Sea. The other form is resident and spawns in brackish water. Both forms utilise the coastal habitat for foraging. We examined the spawning success of the two forms in fresh and brackish water (7 parts per thousand, equal to salinity in thesouth Baltic Sea). The experiments showed that hatching success was equally high in freshwater and in brackish water despite female origin. The survival of yellow-sac and free swimming fry was significantly reduced in brackish water, which was independent if the fish wasof migratory or brackish resident origin. Further, growth rate of perch fry was severely reduced in brackish water. The results indicate thatperch has not developed any tolerance to brackish water in the young life stages. The migratory life strategy of perch can thus be explained by higher survival of fry in freshwater.

Keywords
Fish, perch, Baltic Sea, salinity gradient, growth mortality
National Category
Ecology
Research subject
Ecology, Aquatic Ecology
Identifiers
urn:nbn:se:lnu:diva-19490 (URN)10.1111/j.1600-0633.2011.00537.x (DOI)2-s2.0-84858284810 (Scopus ID)
Projects
Ecochange
Funder
Swedish Research Council Formas
Available from: 2012-06-05 Created: 2012-06-05 Last updated: 2018-10-24Bibliographically approved
Sjöstedt, J., Koch-Schmidt, P., Pontarp, M., Canbäck, B., Tunlid, A., Lundberg, P., . . . Riemann, L. (2012). Recruitment of members from the rare biosphere of marine bacterioplankton communities after an environmental disturbance.. Applied and Environmental Microbiology, 78(5), 1361-1369
Open this publication in new window or tab >>Recruitment of members from the rare biosphere of marine bacterioplankton communities after an environmental disturbance.
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2012 (English)In: Applied and Environmental Microbiology, ISSN 0099-2240, E-ISSN 1098-5336, Vol. 78, no 5, p. 1361-1369Article in journal (Refereed) Published
Abstract [en]

A bacterial community may be resistant to environmental disturbances if some of its species show metabolic flexibility and physiological tolerance to the changing conditions. Alternatively, disturbances can change the composition of the community and thereby potentially affect ecosystem processes. The impact of disturbance on the composition of bacterioplankton communities was examined in continuous seawater cultures. Bacterial assemblages from geographically closely connected areas, the Baltic Sea (salinity 7 and high dissolved organic carbon [DOC]) and Skagerrak (salinity 28 and low DOC), were exposed to gradual opposing changes in salinity and DOC over a 3-week period such that the Baltic community was exposed to Skagerrak salinity and DOC and vice versa. Denaturing gradient gel electrophoresis and clone libraries of PCR-amplified 16S rRNA genes showed that the composition of the transplanted communities differed significantly from those held at constant salinity. Despite this, the growth yields (number of cells ml(-1)) were similar, which suggests similar levels of substrate utilization. Deep 454 pyrosequencing of 16S rRNA genes showed that the composition of the disturbed communities had changed due to the recruitment of phylotypes present in the rare biosphere of the original community. The study shows that members of the rare biosphere can become abundant in a bacterioplankton community after disturbance and that those bacteria can have important roles in maintaining ecosystem processes.

National Category
Microbiology
Research subject
Natural Science, Microbiology
Identifiers
urn:nbn:se:lnu:diva-22845 (URN)10.1128/AEM.05542-11 (DOI)22194288 (PubMedID)2-s2.0-84857065812 (Scopus ID)
Available from: 2012-12-14 Created: 2012-12-12 Last updated: 2019-02-27Bibliographically approved
Engstedt, O., Koch-Schmidt, P. & Larsson, P. (2012). Strontium (Sr) uptake from water and food in otoliths of juvenile pike (Esox lucius L.). Journal of Experimental Marine Biology and Ecology, 418-419, 69-74
Open this publication in new window or tab >>Strontium (Sr) uptake from water and food in otoliths of juvenile pike (Esox lucius L.)
2012 (English)In: Journal of Experimental Marine Biology and Ecology, ISSN 0022-0981, E-ISSN 1879-1697, Vol. 418-419, p. 69-74Article in journal (Refereed) Published
Abstract [en]

The strontium (Sr) or Sr:Ca ratio in otoliths has been widely used in the last decade to describe the migration

histories of fish between fresh and marine waters. However, reference experimental studies of particular

species and waters are necessary to confirm the underlying assumptions and evaluate the applicability of

this tool to field data. Laboratory experiments indicated that juvenile, anadromous pike (Esox lucius L.)

from the Baltic Sea reared in successively increasing salinities (from 0 to 7) for 110 d accumulated Sr

in their otoliths according to a positive relationship with waterborne Sr. When the pike were given prey

fish from brackish (7) environments, the otolith Sr:Ca ratio increased more than in fish given prey

from freshwater lakes. Pike held at constant salinity (7) and given prey fish from the same salinity

environment had an Sr:Ca ratio of 6.9Å~103. The ratio decreased successively for fish given prey

from freshwater (4.4Å~103) or kept in freshwater and given food from brackish water (3.1Å~103).

Fish exposed to freshwater and given prey fish from freshwater displayed no increase in Sr:Ca ratio

(1.6Å~103). The experiments demonstrated that the Sr:Ca ratio may be used to describe the migration

history of pike between rivers and the Baltic Sea. The maximum Sr:Ca value for pike given marineorigin

food corresponded to those of fish collected from the Baltic Sea.

Place, publisher, year, edition, pages
Elsevier, 2012
Keywords
Pike, Baltic Sea, Diet, Sr:Ca, Strontium
National Category
Ecology
Research subject
Natural Science, Aquatic Ecology
Identifiers
urn:nbn:se:lnu:diva-19090 (URN)10.1016/j.jembe.2012.03.007 (DOI)2-s2.0-84859797189 (Scopus ID)
Available from: 2012-05-30 Created: 2012-05-30 Last updated: 2017-12-07Bibliographically approved
Engström, H., Johansson, R., Koch-Schmidt, P., Gregorius, K., Ohlson, S. & Bergström, M. (2008). Evaluation of a glucose sensing antibody using weak affinity chromatography. BMC Biomedical chromotography, 22(3), 272-277
Open this publication in new window or tab >>Evaluation of a glucose sensing antibody using weak affinity chromatography
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2008 (English)In: BMC Biomedical chromotography, ISSN 0269-3879, E-ISSN 1099-0801, Vol. 22, no 3, p. 272-277Article in journal (Refereed) Published
Abstract [en]

Continuous monitoring of drug levels and endogenous molecules in biological fluids is a developing research area with many applications. One example is the need to improve life for millions of diabetes mellitus patients by continuously monitoring the glucose level. In order to have a dynamic response, the recognition molecule in a continuous sensor should preferentially have a fast dissociation rate and a dissociation constant in the millimolar range. We have evaluated the monoclonal antibody (mAb) 3F1E8-A2 for its potential to be used in a future glucose sensor application. The mAb was generated from hybridomas by immunizing mice with 10 kDa dextran (an α1,6-glucose polymer) with the aim of obtaining mAbs that can recognize the glucose monomer. The mAb was immobilized to macroporous silica and the interaction with dextran-derived oligosaccharides was evaluated with weak affinity chromatography (WAC). To measure the low affinities between the mAb 3F1E8-A2 and different monosaccharides, a competitive weak affinity chromatography approach was employed. It was found that the mAb had a higher specificity for glucose compared with other monosaccharides and the dissociation constant (Kd) towards glucose was determined as 18.8 ± 2.6 mm.

Keywords
Glucose, Dextran, Monoclonal antibody, Weak affinity chromatography, Immunosensor
National Category
Natural Sciences
Research subject
Natural Science
Identifiers
urn:nbn:se:hik:diva-647 (URN)10.1002/bmc.924 (DOI)
Available from: 2007-12-13 Created: 2008-11-10 Last updated: 2017-12-13Bibliographically approved
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