Success of stream restoration can be difficult to define because many interacting abiotic and biotic factors across spatio‐temporal scales can have measurable effects. Consequently, failure in habitat restoration to achieve targeted biological goals may reflect interactions of habitat restoration with unaccounted risks that have yet to be addressed on the landscape. This is particularly true within invaded landscapes, where habitat restoration can benefit non‐native competitors as much as the native fishes for which restoration is designed. We tested for interacting effects of a reach scale habitat restoration effort and non‐native trout competition on habitat use by a brook trout (
Despite significant investments in watershed‐scale restoration projects, evaluation of their impacts on salmonids is often limited by inadequate experimental design. This project aimed to strengthen study designs by identifying and quantifying sources of temporal and spatial uncertainty while assessing population‐level salmonid responses in Before‐After‐Control‐Impact (BACI) restoration experiments. To evaluate sources of temporal uncertainty, meta‐analysis of 32 annual BACI experiments from the Pacific Northwest, USA was conducted. Experimental error was determined to be a function of the total temporal variation of both restoration and control salmonid population metrics and the degree of covariation, or synchrony, between these metrics (
- PAR ID:
- 10446277
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- River Research and Applications
- Volume:
- 38
- Issue:
- 5
- ISSN:
- 1535-1459
- Page Range / eLocation ID:
- p. 884-894
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Salvelinus fontinalis ) metapopulation within a productive main stem corridor of the Shavers Fork watershed, West Virginia. We used a joint species occupancy model within a BACI sampling design to show that brook trout occupancy of main stem habitat was highest post‐restoration within restored sampling reaches, but this benefit to native brook trout was conditional on brown trout (Salmo trutta ) not being present within the main stem habitat. Collectively these results indicate that habitat restoration was only beneficial for native brook trout when non‐native trout were absent from the restored sampling area. Proactive approaches to restoration will be integral for supporting resilient ecosystems in response to future anthropogenic threats (e.g. climate change), and we have shown that such actions will only be successful if non‐native competitors do not also benefit from the restoration actions. -
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