Mercury (Hg) is a global atmospheric pollutant that can be harmful to wildlife. Because methylmercury (MeHg) is only produced in aquatic ecosystems, it is assumed that Hg contamination poses a risk to aquatic but not terrestrial wildlife. Tetragnathid spiders transfer aquatic MeHg to terrestrial consumers and may contain high concentrations of MeHg that pose a threat to the health of songbirds that consume them. I collected tetragnathid spiders from 26 sites along three East Texas rivers, Black Cypress, Big Cypress, and Little Cypress Bayou, and determined their Hg concentrations. I then calculated potential Hg risk to four species of songbirds (American Robin, Eastern Bluebird, Carolina Wren, and Chickadee). Average site-specific MeHg concentrations in spiders ranged from 34.5 to 174 ng/g wet weight and were high enough to pose a risk to some songbirds. Mercury concentrations in spiders were significantly different between the rivers and lowest in Big Cypress Bayou.
| Identifer | oai:union.ndltd.org:TCU/oai:etd.tcu.edu:etd-05132014-112556 |
| Date | 13 May 2014 |
| Creators | Powell, Cleveland Hadden |
| Contributors | Ray W Drenner, Matt M Chummchal, Tamie Morgan |
| Publisher | Texas Christian University |
| Source Sets | Texas Christian University |
| Language | English |
| Detected Language | English |
| Type | text |
| Format | application/pdf, application/octet-stream |
| Source | http://etd.tcu.edu/etdfiles/available/etd-05132014-112556/ |
| 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, dissertation, 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 TCU 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 0.0017 seconds