Monitoring and evaluating large-scale, ‘open-ended’ habitat creation projects: A journey rather than a destination

Abstract

Ecological restoration frequently involves setting fixed species or habitat targets to be achieved by prescribed restoration activities or through natural processes. Where no reference systems exist for defining outcomes or where restoration is planned on a large spatial scale, a more ‘open-ended’ approach to defining outcomes may be appropriate. Such approaches require changes to the definition of goals and the design of monitoring and evaluation activities. We suggest that in open-ended projects restoration goals should be framed in terms of promoting natural processes, mobile landscape mosaics and improved ecosystem services. Monitoring can then focus on the biophysical processes that underpin the development of habitat mosaics and the provision of ecosystem services, on the way habitat mosaics change through time and on species that can indicate the changing landscape attributes of connectivity and scale. Stakeholder response should be monitored since an open-ended restoration approach is unusual and can encounter institutional and societal constraints. Evaluation should focus on reporting changing restoration impacts and benefits rather than on achieving a pre-defined concept of ecological success.

Introduction

Dominant approaches to ecological restoration typically aim either to re-establish the status quo ante, or to assemble specified or desirable habitats on degraded land (Jordan & Packard 1989). This may be achieved using established restoration engineering techniques or by allowing natural processes to do some of the work, for example, controlled floods in naturally dynamic habitats such as floodplains (Hughes & Rood 2003). In both cases there is an expectation that over a few years, particular species or habitat targets can be achieved based on predictable biophysical relationships. This approach is proven, and fits the desire of ecological managers, funders, spatial planners and local people to know what the outcomes will be. However, this prescriptive approach does not acknowledge the diverse and often novel starting conditions for much habitat restoration effort (Hughes et al., 2005, Hobbs et al., 2006, Seastedt et al., 2008, Zweig and Kitchens, 2010). Over longer time periods it becomes both less effective and less appropriate to be prescriptive about restoration outcomes (Halle, 2007, Hobbs, 2007). Anthropogenic climate change may further limit the feasibility of restoring historic ecosystem states, and therefore the appropriateness of these as targets or reference conditions (Harris et al. 2006).

An alternative way to think about restoration is to view habitat development as ‘open-ended’, an ecological journey whose destination is uncertain rather than necessarily producing specific habitats or species populations (Hughes et al. 2008). In such situations, the restoration manager allows contemporary (and future) natural processes to dictate ecological outcomes rather than attempting to steer them to fit a pre-selected reference system. However, a restoration project conceived of in this way throws up a number of practical issues, such as how to frame the goals for the project, and how to monitor and evaluate change. In this paper we explore ways of both setting goals and designing monitoring and evaluation approaches for open-ended projects with particular reference to such a project in the UK.