Avtor/Urednik     Maddock, Ian; Thoms, Martin; Jonson, Katarina; Dyer, Fiona; Lintermans, Mark
Naslov     Identifying the influence of channel morphology on physical habitat availability for native fish: application to the two-spined blackfish (Gadopsis bispinosus) in the Cotter river, Australia
Tip     članek
Vir     Marine and freshwater research
Vol. in št.     Letnik 55
Leto izdaje     2004
Obseg     str. 173-84
Jezik     eng
Abstrakt     The impact of channel morphology and flow on physical habitat availability for the two-spined blackfish (Gadopsis bispinosus) was assessed in the Cotter River, ACT, Australia. Physical habitat requirements for three life stages were identified based on previous field sampling in the Cotter River. Two sites were selected with contrasting channel morphology: Spur Hole, with a moderate gradient and runs and glides, and Vanity's Crossing, with a steeper gradient, rapids, and fast-flowing pools. Physical Habitat Simulation System (PHABSIM) was used to simulate the flow v physical habitat availability relationship for each life stage at both sites. Clear differences were apparent between sites, with Spur Hole characterised by increasing habitat with increasing flow and Vanity's Crossing showing the opposite relationship. The nature of the channel morphology determined this difference, with Spur Hole characterised by marginal zones becoming inundated at higher flows and providing additional suitable physical habitat as discharge increases. Vanity's Crossing does not contain similar marginal zones. Further analysis demonstrated that high water velocity was the most important factor limiting physical habitat availability at both sites. This approach demonstrates the importance of channel morphology in determining physical habitat availability and an alternative use of PHABSIM to highlight limiting factors for target species.
Deskriptorji     FRESH WATER
ECOSYSTEM
FISHES
AUSTRALIA