Population connectivity: dam migration mitigations and contemporary site fidelity in arctic char
BACKGROUND: Animal feeding and spawning migrations may be limited by physical barriers and behavioral interactions. Dam constructions (e.g. hydropower) commonly include gateways for fish migrations to sustain ecological connectivity. Relative genetic impacts of fish passage devices versus natural pr...
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fthsbuskerudcom:oai:brage.bibsys.no:11250/2438074 2023-05-15T15:00:34+02:00 Population connectivity: dam migration mitigations and contemporary site fidelity in arctic char Wollebæk, Jens Heggenes, Jan Røed, Knut H. 2012-04-02T11:01:30Z http://hdl.handle.net/11250/2438074 eng eng BioMed Central 488 Journal article Peer reviewed 2012 fthsbuskerudcom 2017-05-21T08:14:07Z BACKGROUND: Animal feeding and spawning migrations may be limited by physical barriers and behavioral interactions. Dam constructions (e.g. hydropower) commonly include gateways for fish migrations to sustain ecological connectivity. Relative genetic impacts of fish passage devices versus natural processes (e.g. hybrid inferiority) are, however, rarely studied. We examined genetic (i.e. microsatellite) population connectivity of highly migrating lake-dwelling Arctic char (Salvelinus alpinus), introduced 20 generations ago, across and within two subalpine lakes separated by a dam with a subterranean tunnel and spill gates after 7 generations. Due to water flow regime, the time window for fish migration is highly restricted. RESULTS: Char populations, with similar genetic structuring and diversity observed across and within lakes, were admixed across the dam with fishways during feeding. For spawning, however, statistically significant, but very low population differentiation (θ; 0.002 - 0.013) was found in nine out of ten reproductive site comparisons, reflecting interactions between extensive migration (mean first generation (F0) = 10.8%) and initial site fidelity. Simulations indicated that genetic drift among relatively small effective populations (mean Ne = 62) may have caused the observed contemporary differentiation. Novel Bayesian analyses indicated mean contributions of 71% F0 population hybrids in spawning populations, of which 76% had maternal or paternal native origin. CONCLUSIONS: Ecological connectivity between lakes separated by a dam has been retained through construction of fishways for feeding migration. Considerable survival and homing to ancestral spawning sites in hybrid progeny was documented. Population differentiation despite preceding admixture is likely caused by contemporary reduced reproductive fitness of population hybrids. The study documents the beginning stages of population divergence among spatial aggregations with recent common ancestry. Published version Article in Journal/Newspaper Arctic Salvelinus alpinus University of South-Eastern Norway: USN Open Archive (Brage) Arctic |
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University of South-Eastern Norway: USN Open Archive (Brage) |
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fthsbuskerudcom |
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English |
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488 |
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488 Wollebæk, Jens Heggenes, Jan Røed, Knut H. Population connectivity: dam migration mitigations and contemporary site fidelity in arctic char |
topic_facet |
488 |
description |
BACKGROUND: Animal feeding and spawning migrations may be limited by physical barriers and behavioral interactions. Dam constructions (e.g. hydropower) commonly include gateways for fish migrations to sustain ecological connectivity. Relative genetic impacts of fish passage devices versus natural processes (e.g. hybrid inferiority) are, however, rarely studied. We examined genetic (i.e. microsatellite) population connectivity of highly migrating lake-dwelling Arctic char (Salvelinus alpinus), introduced 20 generations ago, across and within two subalpine lakes separated by a dam with a subterranean tunnel and spill gates after 7 generations. Due to water flow regime, the time window for fish migration is highly restricted. RESULTS: Char populations, with similar genetic structuring and diversity observed across and within lakes, were admixed across the dam with fishways during feeding. For spawning, however, statistically significant, but very low population differentiation (θ; 0.002 - 0.013) was found in nine out of ten reproductive site comparisons, reflecting interactions between extensive migration (mean first generation (F0) = 10.8%) and initial site fidelity. Simulations indicated that genetic drift among relatively small effective populations (mean Ne = 62) may have caused the observed contemporary differentiation. Novel Bayesian analyses indicated mean contributions of 71% F0 population hybrids in spawning populations, of which 76% had maternal or paternal native origin. CONCLUSIONS: Ecological connectivity between lakes separated by a dam has been retained through construction of fishways for feeding migration. Considerable survival and homing to ancestral spawning sites in hybrid progeny was documented. Population differentiation despite preceding admixture is likely caused by contemporary reduced reproductive fitness of population hybrids. The study documents the beginning stages of population divergence among spatial aggregations with recent common ancestry. Published version |
format |
Article in Journal/Newspaper |
author |
Wollebæk, Jens Heggenes, Jan Røed, Knut H. |
author_facet |
Wollebæk, Jens Heggenes, Jan Røed, Knut H. |
author_sort |
Wollebæk, Jens |
title |
Population connectivity: dam migration mitigations and contemporary site fidelity in arctic char |
title_short |
Population connectivity: dam migration mitigations and contemporary site fidelity in arctic char |
title_full |
Population connectivity: dam migration mitigations and contemporary site fidelity in arctic char |
title_fullStr |
Population connectivity: dam migration mitigations and contemporary site fidelity in arctic char |
title_full_unstemmed |
Population connectivity: dam migration mitigations and contemporary site fidelity in arctic char |
title_sort |
population connectivity: dam migration mitigations and contemporary site fidelity in arctic char |
publisher |
BioMed Central |
publishDate |
2012 |
url |
http://hdl.handle.net/11250/2438074 |
geographic |
Arctic |
geographic_facet |
Arctic |
genre |
Arctic Salvelinus alpinus |
genre_facet |
Arctic Salvelinus alpinus |
_version_ |
1766332659554844672 |