Amphibian biodiversity in Taita Hills, Kenya [Elektronische Ressource] / Kinyatta P. W. Malonza

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Informations

• Publié par: johannes_gutenberg-universitat_mainz
• Publié le: 01 janvier 2008
• Nombre de lectures: 30
• Poids de l'ouvrage: 3 Mo

Extrait

“AMPHIBIAN BIODIVERSITY IN TAITA HILLS, KENYA”

Dissertation
Zur Erlangung des Grades
Doktor der Naturwissenschaften

Am Fachbereich Biologie
Der Johannes Gutenberg-Universität Mainz

Kinyatta P. W. Malonza
geboren am 1 April 1971 in Kitui, Kenia
Mainz im December 19, 2008 iiCONTENTS
1 GENERAL SUMMARY......................................................................................................... 1
2 GENERAL INTRODUCTION .............................................................................................. 3
2.1 Declining amphibian populations .................................................................................... 6
2.2 Habitat alteration and biodiversity loss............................................................................ 6
2.3 Effects of anthropogenic habitat disturbance on amphibians ......................................... 7
2.4 Thesis aims and structure ................................................................................................. 8
3 IS THE LOW AMPHIBIAN BIODIVERSITY IN THE EASTERN ARC MOUNTAINS
DUE TO FOREST LOSS?............................................................................................................ 10
3.1 INTRODUCTION.......................................................................................................... 10
3.2 MATERIALS AND METHODS................................................................................... 13
3.2.1 Study area: Taita Hills, Eastern Arc Mountains ..................................................... 13
3.2.2 Species data............................................................................................................. 15
3.2.3 Forest area and rainfall............................................................................................ 17
3.2.4 Species richness ranking......................................................................................... 17
3.2.5 Amphibian species richness and similarity estimates............................................. 17
3.2.6 Test and analysis methods.....................................................................................18
iii3.3 RESULTS....................................................................................................................... 18
3.3.1 Species richness response to forest area, rainfall, elevation and distant from Indian
Ocean 18
3.3.2 Amphibian species richness ranking....................................................................... 19
3.3.3 Matrix comparison and amphibian community predictability................................ 24
3.4 DISCUSSION ................................................................................................................ 27
3.4.1 The role of rainfall and forest area on amphibian species richness ........................ 28
3.4.2 Amphibian species richness ranking....................................................................... 29
3.4.3 Amphibian community predictability and the uniqueness of Taita Hills ............... 30
3.4.4 Conclusions............................................................................................................. 32
3.5 SUMMARY ................................................................................................................... 33
4 AMPHIBIAN SPECIES DIVERSITY ALONG ELEVATIONAL AND HABITAT
DISTURBANCE GRADIENTS................................................................................................... 34
4.1 INTRODUCTION..........................................................................................................34
4.2 MATERIALS AND METHODS................................................................................... 37
4.2.1 Study area................................................................................................................ 37
4.2.2 Site description.......................................................................................................41
4.2.3 Site selection ........................................................................................................... 41
iv4.2.4 Sampling methods...................................................................................................42
4.2.5 Transect design and sampling................................................................................. 42
4.2.6 Trapping with pitfall traps along drift fences ......................................................... 42
4.2.7 Timed limited searches (TLS) ................................................................................ 42
4.2.8 Taxonomy of the specimens ................................................................................... 43
4.2.9 Species richness and amphibian similarity estimates ............................................. 43
4.2.10 Environmental variables.........................................................................................43
4.2.11 Statistical methods and analysis.............................................................................. 44
4.3 RESULTS.......................................................................................................................46
4.3.2 Species response to abiotic parameters, disturbance level and amphibian
community predictability....................................................................................................... 50
4.4 DISCUSSION................................................................................................................57
4.4.1 Response of species to habitat disturbance, elevation, rainfall and temperature.... 57
4.4.2 Matrix comparison and amphibian community predictability................................ 58
4.4.3 Implications for conservation management ............................................................ 61
4.4.4 Conclusions.............................................................................................................62
4.5 SUMMARY...................................................................................................................63
5 TAITA HILLS’ AMPHIBIAN SPECIES ACCOUNT......................................................... 64
v5.1 INTRODUCTION..........................................................................................................64
5.2 MATERIALS AND METHODS...................................................................................65
5.3 SPECIES ACCOUNT....................................................................................................66
5.4 DISCUSSION................................................................................................................95
5.5 SUMMARY...................................................................................................................97
6 LIFE HISTORY OF A BREVICIPITID FROG, CALLULINA SP.: (AMPHIBIA, ANURA,
BREVICIPITIDAE)...................................................................................................................... 98
6.1 INTRODUCTION..........................................................................................................98
6.2 MATERIALS AND METHODS.................................................................................100
6.2.1 Taxonomy.............................................................................................................100
6.2.2 Study area..............................................................................................................100
6.2.2 Methods.................................................................................................................101
6.3 RESULTS.....................................................................................................................101
6.3.1 Species diagnosis..................................................................................................101
6.3.2 Population and habitat characteristics................................................................... 102
6.3.3 Distribution and forest size ................................................................................... 102
6.3.4 Influence of rainfall, temperature and altitude...................................................... 103
6.3.3 Breeding and other behavioural characteristics .................................................... 106
vi6.4 DISCUSSION..............................................................................................................106
6.4.1 Conservation and management strategy ............................................................... 108
6.5 SUMMARY.................................................................................................................109
7 GENERAL DISCUSSION AND CONCLUSIONS .......................................................... 109
7.1 Conservation and management implications................................................................ 111
8 REFERENCES ................................................................................................................... 112
9 APPENDICES.................................................................................................................... 133
10 ACKNOWLEDGMENTS ............................................................................................... 165

vii1 GENERAL SUMMARY
Species richness v