Thesis
Fish community composition and abundance across a vegetation gradient in a restoring tidal freshwater wetland
Washington State University
Master of Science (MS), Washington State University
2012
Handle:
https://hdl.handle.net/2376/101610
Abstract
Fish assemblages as a function of marsh habitat in restoring freshwater tidal wetlands are poorly understood. We evaluated the seasonal and spatial variation of fish community composition and abundance across a habitat gradient in a restoring tidal wetland in the upper Sacramento-San Joaquin Delta, California. Field sampling occurred at six sites extending across three primary habitat types based on vegetation density and wind exposure. Fish were collected using gill nets and fyke nets in spring 2010, summer 2011, and winter 2012. We collected 466 individual fish representing 23 species, eight of which were native to California. We observed significant seasonal and spatial variation in fish composition and abundance over the three seasons. The highest abundances occurred in spring 2010 and summer 2011 and the lowest abundances occurred in winter 2012. In spring, fish abundance was higher in moderately vegetated habitat, while in summer and winter fish abundance was higher in less vegetated, open water habitat near a levee breach. We used non-metric multidimensional scaling to determine the association between environmental variables and fish community composition and abundance. Seasonal variation largely correlated with water temperature and specific conductance which represented 27% of the variation in fish community composition, while spatial variation represented 52%. Based on our results, we recommend open water habitat containing little to moderately dense vegetation (which fish may use for spawning and rearing) and connectivity with adjacent rivers and sloughs (which allows increased access for fish) be considered in designing and managing tidal marsh restoration.
Metrics
Details
- Title
- Fish community composition and abundance across a vegetation gradient in a restoring tidal freshwater wetland
- Creators
- Sarah Nicole Whitley
- Contributors
- Stephen M. Bollens (Degree Supervisor)
- Awarding Institution
- Washington State University
- Academic Unit
- Environment, School of the (CAHNRS)
- Theses and Dissertations
- Master of Science (MS), Washington State University
- Publisher
- Washington State University; [Pullman, Washington] :
- Identifiers
- 99900525014301842
- Language
- English
- Resource Type
- Thesis