Record Details
Field | Value |
---|---|
Title | Responses of juvenile coho salmon and larval lamprey to instream habitat restoration in a Pacific Northwest stream |
Names |
Gonzalez, Rosalinda
(creator) Dunham, Jason (advisor) |
Date Issued | 2014-12-03 (iso8601) |
Note | Graduation date: 2015 |
Abstract | Large wood has been utilized in many restoration projects to improve in-stream habitat in the Pacific Northwest for salmon. However, the benefits of this practice remain the subject of ongoing debate and evaluation of these projects has scarcely been done for non-salmonid species such as lamprey. In this study we look at the impacts of a large wood restoration on larval Pacific Entosphenus tridentaus and Western Brook Lamprey Lampetra richardsoni and juvenile Coho Salmon Oncorhynchus kisutch by 1) identifying instream habitat characteristics that influence the presence of larval lamprey and abundance of juvenile Coho Salmon; and 2) evaluating how these characteristics are influenced by wood. To address habitat use, we determined presence of larval lamprey in 92 pools and abundance of juvenile Coho Salmon in 44 pools during summer low flows in a small coastal Oregon stream. We focused on a reach of stream where large numbers of large wood pieces and wood jams were introduced to retain sediment in the channel. Results indicate that presence of laval lamprey was associated with availability of fine sediment (P < 0.001) and deeper substrate (P < 0.001). The abundance of juvenile Coho Salmon (fish/pool) was associated with pool area (r[subscript s] = 0.78; P ≤ 0.001) and to a weaker extent with the proportion of cobble and boulder substrates in pools (r[subscript s] = -0.39; P ≤ 0.01). Pools with wood, regardless of whether they were formed by wood, had greater coverage of fine and deeper substrate (P < 0.001) and greater pool area (P = 0.016). Taken together, these results suggest that instream wood can provide habitat conditions that larval lamprey and juvenile Coho Salmon use, and thus provide benefits to these species. |
Genre | Thesis/Dissertation |
Access Condition | http://creativecommons.org/licenses/by-nc-nd/3.0/us/ |
Topic | Juvenile Coho Salmon |
Identifier | http://hdl.handle.net/1957/54662 |