Resilience of imperilled headwater stream fish to an unpredictable high-magnitude flood

• Published in: Koedoe 2015, Vol.57 (1), p.1-1
• Main Authors: Ellender, Bruce R, Weyl, Olaf L F
• Format: Article
• Language: English
• Subjects: Biodiversity Conservation; Environmental Sciences; floods; Freshwater; Natural disturbance; Pseudobarbus afer; resilience
• ISSN: 0075-6458; 2071-0771; 2071-0771
• DOI: 10.4102/koedoe.v57i1.1258

Headwater stream fish communities are increasingly becoming isolated in headwater refugia that are often cut off from other metapopulations within a river network as a result of non-native fish invasions, pollution, water abstraction and habitat degradation downstream. Understanding threats to isolated fish populations is consequently important for their conservation. Following a base-flow survey, a high-magnitude flood provided an opportunity to investigate the response of endangered Eastern Cape redfin Pseudobarbus afer populations to a natural disturbance in the Waterkloof and Fernkloof streams, two relatively pristine headwater tributaries of the Swartkops River system within the Groendal Wilderness Area, Eastern Cape Province, South Africa. This research provides insight into the population level responses of native headwater stream fishes to unpredictable natural disturbance. Of particular relevance is information on their ability to withstand natural disturbances, which provides novel information essential for their conservation and management especially as these fishes are already impacted by multiple anthropogenic stressors.