STREAM CHANNEL MODIFICATION IN HAWAII. PART B: EFFECT OF CHANNELIZATION ON THE DISTRIBUTION AND ABUNDANCE OF FAUNA IN SELECTED STREAMS
Effects of channelization on native Hawaiian stream fauna were assessed by making physio-chemical measurements and analyzing and comparing macrofaunal communities in channelized and unchannelized streams. The altered study streams had higher mean water temperature, pH, and conductivity and wider ranges of these variables than the unaltered stream. Channel sections with concrete bottom had higher values than sections with natural bottom. Exotic fishes predominated in altered streams; exotic fishes and native crustaceans predominated in unaltered streams. Native fishes appeared to be especially reduced in heavily channelized streams. Channels with artificial bottom seemed to provide nurseries for the exotic poeciliids, Poecilia mexicana and P. reticulata; species diversity was lower in these channels. Extreme channelization seems to stress the diadromous native fauna. Channel alterations, particularly artificially lined channels, appear to favor worthless exotics in replacing native species. Channelization in Hawaii should be minimized to protect native fauna. Where it is unavoidable, natural bottom channels seem least damaging. Artificial bottom channels, if used, should provide for reasonable water depth at low flow, and the length of continuous sections should be minimized. Riparian bank vegetation should be maintained. Results of this study are relevant to many tropical oceanic high islands.
University of Hawaii, ManoaHawaii Cooperative Fishery Research Unit
Honolulu, HI USA 96822
Fish and Wildlife ServiceNational Stream Alteration Team
Columbia, MO USA
- Norton, S E
- Timbol, A S
- Parrish, J D
- Publication Date: 1978-5
- Pagination: 59 p.
- TRT Terms: Animals; Channels (Waterways); Crustacea; Culverts; Diversification; Ecology; Environmental impacts; Fishes; Flow; Fresh water; Improvements; Linings; Loss and damage; pH value; Streamflow; Streams; Surveys; Temperature; Tropics; Water quality
- Uncontrolled Terms: Channelization; Conductivity; Fauna; Stream channels
- Geographic Terms: Hawaii
- Old TRIS Terms: Oahu island
- Subject Areas: Bridges and other structures; Environment; Highways; Hydraulics and Hydrology;
- Accession Number: 00192044
- Record Type: Publication
- Source Agency: National Technical Information Service
- Report/Paper Numbers: FWS/OBS-78/77 Final Rpt.
- Contract Numbers: DI-14-16-0008-1199
- Files: TRIS
- Created Date: Jul 11 1979 12:00AM