Genetic characterisation of European grayling populations (Thymallus thymallus L.) [Elektronische Ressource] : implications for conversation and managment / Bernhard Gum

Gumb

Informations

• Publié par: technische_universitat_munchen
• Publié le: 01 janvier 2007
• Nombre de lectures: 38
• Langue: Deutsch
• Poids de l'ouvrage: 3 Mo

Extrait

Department für Ökosystem- und Landschaftsmanagement
Fachgebiet Wildbiologie und Wildtiermanagement


Genetic characterisation of European grayling populations
(Thymallus thymallus L.): Implications for conservation and
management

Bernhard Gum


Vollständiger Abdruck der von der Fakultät Wissenschaftszentrum Weihenstephan
für Ernährung, Landnutzung und Umwelt der Technischen Universität München


zur Erlangung des akademischen Grades eines
Doktors der Naturwissenschaften (Dr. rer. nat.)
genehmigten Dissertation.



Vorsitzender: Univ.-Prof. Dr. Dr. Heinrich H. D. Meyer
Prüfer der Dissertation: 1. Priv.-Doz. Dr. Ralph Kühn
2. Univ.-Prof. Dr. Gerhard Müller-Starck
3. apl. Prof. Dr. Oswald Rottmann


Die Dissertation wurde am 02.11.2006 bei der Technischen Universität München eingereicht
und durch die Fakultät Wissenschaftszentrum Weihenstephan für Ernährung, Landnutzung
und Umwelt am 12.01.2007 angenommen.











To my family
Contents iii
Contents

vi List of figures ……………………………………………………………………...……
List of tables ……………………………………………………………………………. vii
Preface …………………………………………………………………………….......... viii

1 Introduction ……………………………………………………………………….... 1
1.1 Statement of problem ……………………………………………………............. 1
1.2 Aims of the study ………………………………………………………............... 4

2 Literature review ……….………………………………………………………....... 6
2.1 Biology and ecology ………………….………….…………………………......... 6
2.1.1 Systematics and distribution ……………………………………………… 6
2.1.2 Habitat …………………………………………………………………..... 8
2.1.3 Life history traits …………………………………………………………. 10
Mophology and anatomy …………………………………………………. 10
Egg size and fecundity ……………………………………………………. 11
Spawning habitat and spawning behaviour ………….…………………… 13
Hatching, emergence and fry dispersal ….……………………………….. 14
Age and growth rate ……………………………………………………… 16
Feeding …………………………………………………………………… 18
Habitat requirements, migration and homing ………………………..…... 19
Population size and density ………………………………………………. 20
2.2 Genetics …………………………………………………………………………. 22
2.2.1 General aspects …………………………………………………………… 22
Molecular genetic advances …………………………………...…………. 22
Computational and statistical advances ……………………...…………... 23
2.2.2 Grayling genetics …………………………………………………………. 25
2.3 Endangerment of grayling …………………………………………………......... 27
2.3.1 Anthropogenic and environmental impacts on stream-dwelling
fish populations ………………………………………………………........ 28
2.3.2 Bavarian grayling support programme …………………………………… 31

3 Microsatellite variation in Bavarian populations of European grayling
(Thymallus thymallus): Implications for conservation ...…………………………. 35
3.1 Abstract .…………………………………………………………………………. 35
3.2 Introduction ……………………………………………………………………... 36
3.3 Materials and methods …………………………………………………………... 38
3.3.1 Sample collection …………………………………………………………. 38
3.3.2 DNA isolation and microsatellite analysis ..…………………………........ 38
3.3.3 Data analysis ……………………………………………………………… 41
3.4 Results …………………………………………………………………………... 44
3.4.1 Linkage and Hardy-Weinberg equilibrium tests …………………………. 44
3.4.2 Genetic diversity between and within the drainages ……………………... 44
3.4.3 Genetic differentiation and relationship of populations ………………….. 45
3.5 Discussion ……………………………………………………………………….. 49
3.5.1 Genetic diversity between and within drainages …………………………. 49
3.5.2 Genetic differentiation between drainages ……………………………….. 51
3.5.3 Conservation and management implications ……………………………... 52
3.6 Supplementary material ………………………….……………………………… 53 Contents iv

4 Mitochondrial and nuclear DNA phylogeography of European grayling
(Thymallus thymallus): evidence for secondary contact zones in Central Europe 54
4.1 Abstract ………………………………………………………………………….. 54
4.2 Introduction …………………………………………………………………….... 55
4.3 Materials and methods …………………………………………………………... 58
4.3.1 Sample collection and DNA isolation ……………………………………. 58
4.3.2 Mitochondrial DNA analysis ……………………………………………... 58
4.3.3 Microsatellite DNA analysis ……………………………………………… 59
4.3.4 Data analysis ……………………………………………………………… 63
4.4 Results …………………………………………………………………………… 65
4.4.1 Mitochondrial DNA diversity and phylogenetic inference ………………. 65
4.4.2 Geographic distribution of mtDNA haplotypes and differentiation
among assemblages ………………………………………………………. 70
4.4.3 Microsatellite DNA variation within and between samples ……………… 71
4.4.4 Microsatellite divergence and admixture analysis among assemblages ….. 72
4.4.5 Analysis of molecular variance …………………………………………... 74
4.5 Discussion ……………………………………………………………………….. 76
4.5.1 Diversity and divergence of grayling mtDNA and nuclear DNA ………... 76
4.5.2 Colonization history and postglacial dispersal of Thymallus thymallus ….. 78
4.5.3 Zones of hybridization in central and northern Europe …………………... 79
4.5.4 Comparative phylogeographical inference ……………………………….. 80
4.5.5 Implications for conservation …………………………………………….. 81
4.6 Supplementary material …………………………………………………………. 82

5 Discriminating the impact of recent human mediated stock transfer
from historical gene flow on genetic structure of European grayling
(Thymallus thymallus L.) …………………………………………………………... 83
5.1 Abstract ………………………………………………………………………… 83
5.2 Introduction …………………………………………………………………….. 83
5.3 Sample collection and stocking history ………………………………………… 85
5.4 Methods ………………………………………………………………………… 91
5.4.1 DNA isolation and genetic analysis ……………………………………… 91
5.4.2 Data analysis ……………………………………………………………… 91
5.5 Results ………………………………………………………………………….. 95
5.5.1 MtDNA diversity and geographical distribution of mtDNA haplotypes … 95
5.5.2 Microsatellite DNA variation within and between samples ……………... 95
5.5.3 Microsatellite divergence and admixture analysis ……………………….. 96
5.5.4 Individual immigrant ancestries ………………………………………….. 98
5.5.5 Discrimination of historical secondary contact from recent human
mediated stock transfer …………………………………………………... 98
5.6 Discussion …………………………………………………………………...…. 101
5.6.1 Genetic impact of stocking on genetic structure of European grayling …. 102
5.6.2 Conservation priorities …………………………………………………… 104

6 General Discussion ……………………....................……………………………… 107
6.1 Application of mitochondrial and microsatellite DNA markers in
conservation genetics: general considerations ………………….……………… 107
6.1.1 Mitochondrial DNA ……………………………………………………… 107
6.1.2 Microsatellite DNA ………………………………………………………. 109
6.2 Conservation genetics of European grayling …………………………………... 111 Contents v

6.2.1 General aspects ………………………………………………………….. 111
6.2.2 Salmonid population genetic structure based on microsatellite
DNA analyses …………………………………………………………… 111
6.2.3 Phylogeograpic inference of European grayling with particular
reference to salmonids and other European freshwater fish species ……. 116
6.3 Implications for conservation and management ……………………………….. 122
6.3.1 Contribution of conservation genetics ...………………………………… 122
6.3.2 Contribution of ongoing studies and other fields of research …………… 126
6.4 Perspectives ……………………………………………………………………. 132

7 Summary ……………………...………....................………………………………. 136

8 Zusammenfassung ……………………....................………………………………. 138

9 References ……………………....................……………………………………..…. 141

10 Acknowledgements …………………....................……………………………..…. 165 List of figures vi
List of figures

Fig. 2.1: Adult male European grayling (Thymallus thymallus L.) …………………….. 10

Fig. 2.2: Comparison between relative ratio of body height for European grayling
from drainages Danube, Main and Elbe ………………………………………. 11

Fig. 2.3: Growth rates of European grayling populations from different drainage
systems in Bavaria …………………………………………………………….. 17

Fig. 2.4: Development of annual European grayling catches from 1975 to 1999
averaged over 26 Bavarian rivers of the Alpine Danubian drainage syste