Genetic and Ecological Consequences of Fish Releases : With Focus on Supportive Breeding of Brown Trout Salmo trutta and Translocation of European Eel Anguilla anguilla
Although the practice of releasing fish into the wild is common in the management and conservation of fish populations, the success of release programmes and the potential harmful genetic and ecological effects that may follow are rarely considered. This thesis focuses on genetic and ecological cons...
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Uppsala universitet, Populationsbiologi
2003
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ftuppsalauniv:oai:DiVA.org:uu-3764 2023-05-15T13:27:30+02:00 Genetic and Ecological Consequences of Fish Releases : With Focus on Supportive Breeding of Brown Trout Salmo trutta and Translocation of European Eel Anguilla anguilla Dannewitz, Johan 2003 application/pdf http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-3764 eng eng Uppsala universitet, Populationsbiologi Uppsala : Acta Universitatis Upsaliensis Comprehensive Summaries of Uppsala Dissertations from the Faculty of Science and Technology, 1104-232X 906 http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-3764 urn:isbn:91-554-5796-7 info:eu-repo/semantics/openAccess Biology conservation fishery management panmixia genetic variation effective population size hatchery selection Biologi Doctoral thesis, comprehensive summary info:eu-repo/semantics/doctoralThesis text 2003 ftuppsalauniv 2023-02-23T21:44:16Z Although the practice of releasing fish into the wild is common in the management and conservation of fish populations, the success of release programmes and the potential harmful genetic and ecological effects that may follow are rarely considered. This thesis focuses on genetic and ecological consequences of fish releases, exemplified by supportive breeding of brown trout (Salmo trutta) and translocation of European eel (Anguilla anguilla). Specific questions addressed include: What is the relative performance of hatchery produced fish released to support wild populations, and do released hatchery fish contribute to the natural productivity? What is the variation in reproductive success in the wild, and how does it affect the genetic consequences of a supportive breeding programme? Is there a spatial genetic structure in the European eel that must be considered in the management of this rapidly declining species? Experiments conducted under natural and near-natural conditions in the River Dalälven, Sweden, suggest that hatchery produced trout can reproduce in the wild. In fact, when the pronounced variation between individual breeders was accounted for, there were no detectable differences between hatchery produced and wild born trout in reproductive success or offspring survival. These results were supported by molecular genetic data suggesting a pronounced gene flow from hatchery to wild trout in the river. Hatchery reared trout were, however, found to exhibit reduced survival rates immediately following release into the wild, an effect that was most likely due to phenotypic responses to the hatchery environment during ontogeny and a lack of experience of the wild. In sharp contrast to recently published studies, the present genetic analyses of European eels sampled across the whole distribution range suggest no spatial genetic structure but a subtle temporal genetic heterogeneity within sampled locations. These results emphasise the need to consider temporal replication when assessing population structure ... Doctoral or Postdoctoral Thesis Anguilla anguilla European eel Uppsala University: Publications (DiVA) |
institution |
Open Polar |
collection |
Uppsala University: Publications (DiVA) |
op_collection_id |
ftuppsalauniv |
language |
English |
topic |
Biology conservation fishery management panmixia genetic variation effective population size hatchery selection Biologi |
spellingShingle |
Biology conservation fishery management panmixia genetic variation effective population size hatchery selection Biologi Dannewitz, Johan Genetic and Ecological Consequences of Fish Releases : With Focus on Supportive Breeding of Brown Trout Salmo trutta and Translocation of European Eel Anguilla anguilla |
topic_facet |
Biology conservation fishery management panmixia genetic variation effective population size hatchery selection Biologi |
description |
Although the practice of releasing fish into the wild is common in the management and conservation of fish populations, the success of release programmes and the potential harmful genetic and ecological effects that may follow are rarely considered. This thesis focuses on genetic and ecological consequences of fish releases, exemplified by supportive breeding of brown trout (Salmo trutta) and translocation of European eel (Anguilla anguilla). Specific questions addressed include: What is the relative performance of hatchery produced fish released to support wild populations, and do released hatchery fish contribute to the natural productivity? What is the variation in reproductive success in the wild, and how does it affect the genetic consequences of a supportive breeding programme? Is there a spatial genetic structure in the European eel that must be considered in the management of this rapidly declining species? Experiments conducted under natural and near-natural conditions in the River Dalälven, Sweden, suggest that hatchery produced trout can reproduce in the wild. In fact, when the pronounced variation between individual breeders was accounted for, there were no detectable differences between hatchery produced and wild born trout in reproductive success or offspring survival. These results were supported by molecular genetic data suggesting a pronounced gene flow from hatchery to wild trout in the river. Hatchery reared trout were, however, found to exhibit reduced survival rates immediately following release into the wild, an effect that was most likely due to phenotypic responses to the hatchery environment during ontogeny and a lack of experience of the wild. In sharp contrast to recently published studies, the present genetic analyses of European eels sampled across the whole distribution range suggest no spatial genetic structure but a subtle temporal genetic heterogeneity within sampled locations. These results emphasise the need to consider temporal replication when assessing population structure ... |
format |
Doctoral or Postdoctoral Thesis |
author |
Dannewitz, Johan |
author_facet |
Dannewitz, Johan |
author_sort |
Dannewitz, Johan |
title |
Genetic and Ecological Consequences of Fish Releases : With Focus on Supportive Breeding of Brown Trout Salmo trutta and Translocation of European Eel Anguilla anguilla |
title_short |
Genetic and Ecological Consequences of Fish Releases : With Focus on Supportive Breeding of Brown Trout Salmo trutta and Translocation of European Eel Anguilla anguilla |
title_full |
Genetic and Ecological Consequences of Fish Releases : With Focus on Supportive Breeding of Brown Trout Salmo trutta and Translocation of European Eel Anguilla anguilla |
title_fullStr |
Genetic and Ecological Consequences of Fish Releases : With Focus on Supportive Breeding of Brown Trout Salmo trutta and Translocation of European Eel Anguilla anguilla |
title_full_unstemmed |
Genetic and Ecological Consequences of Fish Releases : With Focus on Supportive Breeding of Brown Trout Salmo trutta and Translocation of European Eel Anguilla anguilla |
title_sort |
genetic and ecological consequences of fish releases : with focus on supportive breeding of brown trout salmo trutta and translocation of european eel anguilla anguilla |
publisher |
Uppsala universitet, Populationsbiologi |
publishDate |
2003 |
url |
http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-3764 |
genre |
Anguilla anguilla European eel |
genre_facet |
Anguilla anguilla European eel |
op_relation |
Comprehensive Summaries of Uppsala Dissertations from the Faculty of Science and Technology, 1104-232X 906 http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-3764 urn:isbn:91-554-5796-7 |
op_rights |
info:eu-repo/semantics/openAccess |
_version_ |
1766398804181909504 |