A Review of Approaches for Monitoring the Effectiveness of Regional River Habitat Restoration Programs

Abstract

Large regional programs to restore riverine habitat for fish and aquatic organisms have become common throughout North America, Europe, and elsewhere. Evaluating the effectiveness of projects implemented under these programs—sometimes called programmatic monitoring and evaluation—has proven challenging, and little guidance exists on programmatic monitoring and evaluation approaches and their effectiveness. In this paper, we review different approaches for evaluating the effectiveness of river restoration projects implemented across a region. These programmatic monitoring and evaluation approaches include case studies, meta‐analyses, multiple before–after control–impact (mBACI), extensive posttreatment (EPT), intensively monitored watersheds (IMWs), and hybrid programmatic approaches that use a combination of different experimental designs. For each approach, we discuss the pros and cons as well as provide examples. The most appropriate approach depends in part on the questions that the programmatic monitoring and evaluation strives to address, the spatial and temporal scale at which detection of a response is expected, and the scale of inference. Case studies and mBACI approaches can answer questions about individual projects but have several limitations in terms of cost, timely results, and feasibility. A meta‐analysis, which can provide broadly applicable results, is dependent upon a large number of case studies being completed. The EPT approach can provide relatively quick and easy‐to‐interpret results, but it requires a large population of completed projects and careful selection of controls. The IMW approach has been broadly applied in western North America but has had limited success and appears to be tractable only in small catchments where restoration and monitoring can be well controlled. Based on results from recent efforts in the USA and Europe, the most feasible programmatic monitoring and evaluation approach in terms of cost, implementability, and production of timely results appears to be a hybrid approach that uses a combination of the EPT and mBACI approaches.

Beyond Redistribution: In‐Stream Habitat Restoration Increases Capacity for Young‐of‐the‐Year Chinook Salmon and Steelhead in the Entiat River, Washington

“…A BACI design does not depend on this assumption and only requires that a treated area show a greater positive change, relative to an untreated area, following the treatment (Roni et al. , 2018a, 2018b; Conner et al. ).…”

“…Moreover, although BACI studies enable detection of effects at spatial scales from habitat units to whole reaches (Roni et al. 2018a), they are only possible when there are adequate pretreatment data, which is difficult to ensure unless restoration projects are planned well in advance. At larger scales, such as comparing whole reaches, most effectiveness study designs, including BACI, are subject to replication issues (Stewart‐Oaten et al.…”

Comparison of Sampling Methods for Small Oxbow wetland Fish Communities

“…Wetland restoration activities range in scope and complexity from watershed-scale undertakings to targeted fine-scale enhancements of habitats. As these activities have expanded, so has realization of the value of monitoring sites post-restoration to assess management successes or failures (Rubin et al 2017;Roni et al 2018). Standardized monitoring protocols are imperative for comparing success of different restoration strategies and responses of different types of wetlands to these management actions.…”

“…Standardized monitoring protocols are imperative for comparing success of different restoration strategies and responses of different types of wetlands to these management actions. (Roni et al 2018).…”

Scale of monitoring influences interpretation of stream habitat restoration results for juvenile Chinook salmon

“…This method, however, requires separate surveys of treated and untreated habitat within a treated reach at a relatively small (microhabitat) scale. If effectiveness monitoring is conducted at the reach scale, as is the goal of many monitoring programs (Roni et al 2013b(Roni et al , 2018a, total fish density will integrate all habitats combined (Beechie et al 2005). Depending on the ratio of restored to unrestored area, the increased fish density in restored habitats might be diluted quickly, especially if the ELJs have very localized effects.…”