13 Priority Rivers for Alien Fish Eradication
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13 Priority Rivers for Alien Fish Eradication Riaan van der Walt Dean Impson Martine Jordaan 30 May 2013 1. Native species 1. Biedouw River • Clanwilliam sandfish E • Clanwilliam yellowfish V • Clanwilliam sawfin E • Clanwilliam redfin V • Cape galaxias DD 2. Alien species • spotted bass • smallmouth bass 3. Barrier • Funding for EIA 2013/2014 4. Other threats • Alien vegetation • Water abstraction 5. Conservation initiatives • Awareness with landowners • Sandfish BMPS • Possible alien clearing project – Wupperthal Native fish upper limit 6. Rehabilitation area Alien fish upper limit • 2 km, needs alien veg. clearing Biedouw River, Cederberg Biedouw River, Cederberg 2. Jan Dissels River 1. Native species • Clanwilliam yellowfish V • Clanwilliam sawfin E • Clanwilliam redfin V • Clanwilliam rock catfish V (spotted) • Cape galaxias V • Fiery redfin (extirpated) 2. Alien species • smallmouth bass • Bluegill sunfish • Banded tilapia 3. Barrier • Owner willing to erect and fund barrier 4. Other threats • Alien vegetation 5. Conservation initiatives • Catchment in Cederberg wilderness Alien fish upper limit 6. Rehabilitation area Native fish upper limit • 6 km near pristine wilderness 1. Native species 3. Heks River • Spotted rock catfish E • Clanwilliam rock catfish V • Clanwilliam yellowfish V • Fiery redfin E • Clanwilliam redfin V • Cape galaxias DD 2. Alien species • smallmouth bass 3. Barrier • Funding required 4. Other threats • Alien vegetation 5. Conservation initiatives • Catchment: Cederberg Wilderness 6. Rehabilitation area • 7-10 km pristine habitat Native fish upper limit Alien fish upper limit 1. Native species • Doring redfin CR 4. Breekkrans River • Clanwilliam yellowfish V • Clanwilliam sawfin E • Clanwilliam redfin V • Chubbyhead barb DD • Cape galaxias DD 2. Alien species • spotted bass • smallmouth bass 3. Barrier • Funding for EIA 2013/2014 4. Other threats • Fire ? 5. Conservation initiatives • Stewardship site • Catchment: Cape Mountain Club and Cederberg Wilderness Native fish upper limit Alien fish upper limit 6. Rehabilitation area • 3-4 km pristine habitat Breekkrans River, Cederberg 1. Native species • Twee River redfin CR 5. Twee River • Twee River galaxias DD 2. Alien species • largemouth bass (dam) • Bluegill sunfish • Cape kurper (below waterfall) • Clanwilliam yellowfish (below waterfall) 3. Barrier • Barrier at Suurvlei planned 2014/2015 Working for Wetlands 4. Other threats • Agricultural pollution and water abstraction • Alien vegetation 5. Conservation initiatives • Alien clearing proposal WWF Green Trust • Part of Cape Critical Rivers Project: EWT 1. Native species 6. Middeldeur • Twee River redfin CR • Twee River galaxias DD 2. Alien species • largemouth bass (dam) • Bluegill sunfish • Cape kurper (below waterfall) • Clanwilliam yellowfish (below waterfall) 3. Barrier • Natural waterfall at De Straat but none lower down 4. Other threats • Agricultural pollution and water abstraction • Hex River only sanctuary 5. Conservation initiatives • Catchment: Hexberg NR and Tandfontein PNR • Awareness • WWF Greentrust 1. Native species • Verlorenvlei redfin CR 7. Krom Antonies • Cape galaxias x2 • Cape kurper DD 2. Alien species • largemouth bass • Bluegill sunfish • Banded tilapia 3. Barrier • Funding needed • Temporary barriers, phased 4. Other threats • Agricultural pollution and water abstraction • Mining for tungsten 5. Conservation initiatives • Alien clearing by Working for Wetlands • Awareness from mining threat 8. Krom River 1. Native species • Giant redfin CR 2. Alien species • smallmouth bass • Rainbow trout 3. Barrier • Funding required 4. Other threats • recreation 5. Conservation initiatives • Catchment in Limietberg NR • CPS assistance Native fish upper limit Alien fish upper limit 1. Native species • Giant redfin CR 9. Upper Riviersonderend • Cape kurper DD • Breede redfin LC • Cape galaxias V 2. Alien species • smallmouth bass ? • Bluegill sunfish ? • Sharptooth catfish ? 3. Barrier • Funding required to create sanctuary 4. Other threats • Alien vegetation 5. Conservation initiatives • Hottentots Holland NR 10. Kars River 1. Native species • Heuningnes redfin CR • Cape kurper DD • Cape galaxias DD 2. Alien species • spotted bass • Bluegill sunfish 3. Barrier • Funding required 4. Other threats • Alien vegetation • Water abstraction 5. Conservation initiatives • none Native fish upper limit Alien fish upper limit 1. Native species 11. Poort River • Heuningnes redfin CR • Cape kurper DD ? • Cape galaxias DD 2. Alien species • spotted bass • Bluegill sunfish 3. Barrier • Funding required 4. Other threats • Alien vegetation • Water abstraction • Habitat degradation 5. Conservation initiatives • Agulhas Biodiversity Initiative 12. Tradou River 1. Native species • Tradou redfin CR 2. Alien species • Largemouth bass • Bluegill sunfish • Banded tilapia 3. Barrier • funding required 4. Other threats • Alien vegetation • Water abstraction • Water pollution 5. Conservation initiatives • Draft BMP and SOS project 1. Native species • Tradou redfin CR 13. Huis River 2. Alien species • largemouth bass • Bluegill sunfish • Banded tilapia 3. Barrier • Funding required 4. Other threats • Alien vegetation • Water abstraction • Water pollution 5. Conservation initiatives • BMP and SOS project Thanks .