If you are experiencing problems downloading PDF or HTML fulltext, our helpdesk recommend clearing your browser cache and trying again. If you need help in clearing your cache, please click here . Still need help? Email help@ingentaconnect.com

Influence of largemouth bass, Micropterus salmoides, on abundance and habitat selection of Cape galaxias, Galaxias zebratus, in a mountain stream in the Cape Floristic Region, South Africa

$53.74 plus tax (Refund Policy)

Buy Article:

Abstract:

Predatory alien fishes have been widely introduced into streams in the Cape Floristic Region (CFR), South Africa, but little is known about their effect on native fishes. Results from this 2006 study suggest that the presence of alien predatory largemouth bass, Micropterus salmoides, may have influenced abundance and habitat selection of the native Galaxias zebratus at one location in a small CFR mountain stream. Numbers of adults, but not of juveniles, were significantly lower where M. salmoides was present, suggesting a size-specific influence on G. zebratus abundance. Because other studies have found the influence of a predator to be affected by prey size and the diel activity of predator and prey, we measured microhabitat use by adult and juvenile G. zebratus by day and by night. Galaxias zebratus selected deeper, faster-flowing microhabitats more strongly where M. salmoides was present than where it was absent. This suggests that G. zebratus adjusts its habitat use in the presence of M. salmoides, although differences in available habitat, or in interactions with other indigenous species, could be partly responsible for the observed differences. In-stream vegetation presence was strongly positively related to depth and strongly negatively related to velocity at positions where G. zebratus was observed, suggesting that the deeper, slower-flowing microhabitats occupied by G. zebratus were structurally more complex than the shallower, faster-flowing ones.

Keywords: ALIEN SPECIES IMPACTS; DIEL ACTIVITY; MICROHABITATS; NATIVE GALAXIID FISH; PREDATORY ALIEN FISH

Document Type: Research Article

DOI: http://dx.doi.org/10.2989/AJAS.2008.33.3.2.614

Publication date: December 1, 2008

More about this publication?
  • Co-Published by NISC and Taylor & Francis - Subscriber access available here
Related content

Share Content

Access Key

Free Content
Free content
New Content
New content
Open Access Content
Open access content
Subscribed Content
Subscribed content
Free Trial Content
Free trial content
Cookie Policy
X
Cookie Policy
ingentaconnect website makes use of cookies so as to keep track of data that you have filled in. I am Happy with this Find out more