Barriers to fish passage
In order to maintain populations, fish and many other aquatic organisms need to move between habitat areas within waterways. Some can migrate very long distances between particular locations in a waterway and the open ocean. Regulation of waterways, e.g. dams and weirs and periods of very low or no flow that result in physical obstruction and/or pooling that may inhibit fish passage. These barriers can have serious implications for the viability of some aquatic species (e.g. reduced breeding potential or death) and subsequently negative impacts on biodiversity.
Suggested indicator: In-stream habitat+
Barriers to fish passage may be associated with:
|Potential associated impacts||Suggested indicators+|
|Habitat and fish population fragmentation||
Reduced access to spawning areas leading to:
|Reduced access to feeding areas||
|Reduced food supplies for dependant terrestrial and aquatic species leading to reduced numbers||
+ Descriptions of indicators (PDF, 76K)* provides a brief description of each indicator including techniques and purpose.
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Last updated 7 September 2010