Population Connectivity of Two Australian Freshwater Fishes in a Large Tropical Dendritic River Network

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Author(s)
Primary Supervisor
Hughes, Jane
Other Supervisors
Schmidt, Daniel
Year published
2016
Metadata
Show full item recordAbstract
Freshwater fishes are often characterized by extensive population genetic subdivision and low genetic diversity and are ideal subjects for investigating contemporary patterns of dispersal and subsequent gene flow. In lotic systems, different riverine architecture, variable hydrology and species biology influence genetic diversity and population structure in resident species. Stream-dwelling species often display greater levels of gene flow within drainages or catchments or sub-catchments than between them due to complexity of stream order and the isolating nature of these systems by land or sea.
However, the relative importance ...
View more >Freshwater fishes are often characterized by extensive population genetic subdivision and low genetic diversity and are ideal subjects for investigating contemporary patterns of dispersal and subsequent gene flow. In lotic systems, different riverine architecture, variable hydrology and species biology influence genetic diversity and population structure in resident species. Stream-dwelling species often display greater levels of gene flow within drainages or catchments or sub-catchments than between them due to complexity of stream order and the isolating nature of these systems by land or sea. However, the relative importance of these attributes in driving population structure at spatial scales remains poorly understood for many freshwater species. Study on the effects of riverscape in shaping population structure is very important to identify management or conservation units and to undertake habitat restoration measures. The Daly River is one of the largest river networks in the wet-dry tropics of Northern Australia and shows variability in hydrology. This river has a complex arrangement of habitats and heterogeneous landscape features (e.g. slope, elevation) across the catchment area. There are also instream physical barriers like waterfalls, cliffs, road crossings etc. that may hinder dispersal and subsequent gene flow.
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View more >Freshwater fishes are often characterized by extensive population genetic subdivision and low genetic diversity and are ideal subjects for investigating contemporary patterns of dispersal and subsequent gene flow. In lotic systems, different riverine architecture, variable hydrology and species biology influence genetic diversity and population structure in resident species. Stream-dwelling species often display greater levels of gene flow within drainages or catchments or sub-catchments than between them due to complexity of stream order and the isolating nature of these systems by land or sea. However, the relative importance of these attributes in driving population structure at spatial scales remains poorly understood for many freshwater species. Study on the effects of riverscape in shaping population structure is very important to identify management or conservation units and to undertake habitat restoration measures. The Daly River is one of the largest river networks in the wet-dry tropics of Northern Australia and shows variability in hydrology. This river has a complex arrangement of habitats and heterogeneous landscape features (e.g. slope, elevation) across the catchment area. There are also instream physical barriers like waterfalls, cliffs, road crossings etc. that may hinder dispersal and subsequent gene flow.
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Thesis Type
Thesis (PhD Doctorate)
Degree Program
Doctor of Philosophy (PhD)
School
Griffith School of Environment
Copyright Statement
The author owns the copyright in this thesis, unless stated otherwise.
Item Access Status
Public
Subject
Freshwater fishes
Daly River
Daly River ecology
Dendritic river system