Introduced species are a threat to native species conservation worldwide and can cause an overall reduction in biodiversity. In the Cape Horn Biosphere Reserve in southern Chile, introduced beaver and trout are highly successful invaders in the landscape and alter stream ecosystem function. Our research suggests introduced beaver create favorable feeding habitats for native puye (Galaxias maculatus) by increasing available macrobenthic biomass and creating ideal feeding conditions for puye. A negative effect of trout on puye was only detectable in favorable beaver-altered habitats where puye abundance was significantly reduced. A negative relationship between trout density and aquatic macrobenthic biomass suggests introduced trout reduce prey availability at the patch-scale. Our findings also show the presence of endangered Aplochiton spp. on Navarino and Hoste islands and the absence of brown trout completely from the southeast fringe of the Cape Horn Biosphere Reserve. Conservation measures be taken to prevent the spread of brown trout into the area in order to protect rare Aplochitons spp. These results emphasize the need for understanding introduced species distributions and their influence on native biota and stream ecology so conservation measures to preserve native species and the pristine status of the Cape Horn Biosphere Reserve can be implemented.
| Identifer | oai:union.ndltd.org:NCSU/oai:NCSU:etd-02282007-215241 |
| Date | 06 April 2007 |
| Creators | Moorman, Michelle |
| Contributors | David B. Eggleston, Wayne Starnes, Jason Osborne |
| Publisher | NCSU |
| Source Sets | North Carolina State University |
| Language | English |
| Detected Language | English |
| Type | text |
| Format | application/pdf |
| Source | http://www.lib.ncsu.edu/theses/available/etd-02282007-215241/ |
| Rights | unrestricted, I hereby certify that, if appropriate, I have obtained and attached hereto a written permission statement from the owner(s) of each third party copyrighted matter to be included in my thesis, dis sertation, or project report, allowing distribution as specified below. I certify that the version I submitted is the same as that approved by my advisory committee. I hereby grant to NC State University or its agents the non-exclusive license to archive and make accessible, under the conditions specified below, my thesis, dissertation, or project report in whole or in part in all forms of media, now or hereafter known. I retain all other ownership rights to the copyright of the thesis, dissertation or project report. I also retain the right to use in future works (such as articles or books) all or part of this thesis, dissertation, or project report. |
Page generated in 0.0016 seconds