Record Details
Environmental correlates of parasitism in introduced threespine stickleback (Gasterosteus aculeatus) in the Upper Deschutes River Basin, Oregon
ScholarsArchive at Oregon State University
| Field | Value |
|---|---|
| Title | Environmental correlates of parasitism in introduced threespine stickleback (Gasterosteus aculeatus) in the Upper Deschutes River Basin, Oregon |
| Names |
Koketsu, Wataru
(creator) Edge, W. Daniel (advisor) |
| Date Issued | 2004-04-19 (iso8601) |
| Note | Graduation date: 2004 |
| Abstract | The Pseudophyllidean tapeworm, Schistocephalus solidus, is a parasite that requires both copepods and fish, mainly the threespine stickleback (Gasterosteus aculeatus) as intermediate hosts, and birds as its final host to complete its life cycle. A rapid increase in the abundance of both the non-native stickleback and the tapeworm in the Upper and Middle Deschutes Basin began in the late 1990s. To determine environmental factors that correlate with higher infection levels, fish and water quality data were collected at 77 sites during the summer of 2003 using a stratified random sampling design. The sites at which stickleback were infected with the parasite were concentrated both in the Crane Prairie and Wickiup reservoirs area. Multiple regression and logistic regression analyses showed mean size of stickleback, catch-per-unit- effort, and water flow were significantly related to parasite prevalence (the percentage of hosts that are infected with the parasite) and mean infection intensity (mean number of parasite per fish). These occurrences were likely associated with human-altered habitat. A differential equation model was developed to characterize the parasite distribution among the host populations. This equation may serve to quantify and compare the impact of the parasite in host populations among basins or among different parasite species. |
| Genre | Thesis/Dissertation |
| Topic | Pseudophyllidea -- Oregon -- Deschutes River Watershed |
| Identifier | http://hdl.handle.net/1957/20453 |
