Andean Streams in Agricultural Landscapes: Degraded Habitats or Biodiversity Reservoirs

Citation

Chara J, Baird DJ & Telfer T (2001) Andean Streams in Agricultural Landscapes: Degraded Habitats or Biodiversity Reservoirs. In: volume 18. 49th Annual Meeting of the North American Benthological Society, LaCrosse, WI, USA, 03.06.2001-08.06.2001. North American Benthological Society, p. 43.

Abstract
Studies on aquatic biodiversity in the tropics tend to focus on preservation of pristine areas. However, streams draining agricultural landscapes may be important reservoirs of diversity. Here we study Andean streams that flow through agricultural landscapes, focusing on the status of the endemic catfish genus Trichomycterus. Six streams in the Cauca Valley of western Colombia were sampled on a monthly basis in order to determine the status of Trichomycterus in relation to its food supply (macroinvertebrates), and physico-chemical habitat. Fish were sampled by electrofishing and samples taken for dietary analysis. Macroinvertebrates were collected using a Surber sampler. Trichomycterus populations were present in all streams, with limited seasonality of occurrence. In these streams, Trichomycterus is a benthic carnivore, feeding largely on chironomids and mayflies. Detrended correspondence analysis of the macroinvertebrate data showed separation of sites by location, with little obvious seasonal trend. Combined with physical habitat data, ordinations suggested that differences among sites were driven by stream size and flow regime, indicating dominance of the physical habitat. These preliminary investigations have indicated that streams draining agricultural watersheds in the Andes can maintain a diverse aquatic fauna, indicating the possibility that conservation and agricultural practices are not mutually exclusive activities.

Journal
Bulletin of the North American Benthological Society: Volume 18, Issue 1