The creation of compensatory habitat—Can it secure sustainable development?

Abstract

We review the effectiveness of habitat creation in an attempt to better understand the potential for delivery of compensatory habitat as part of sustainable development solutions, or for the establishment of habitat banking. Our review highlights considerable differences in the timescales needed to create conservation habitat of a comparable quality. Some wetlands may take just a few years, some grasslands of nature conservation value are known to be relatively young (<80 years old), but woodlands may need to be hundreds of years old before they achieve a similar level of interest. Our knowledge of the abiotic requirements for some habitats, for example hydrological conditions for alkaline fens, is poor and suitable conditions are rare, making re-creation of such habitats highly problematic. Some faunas, such as some dragonfly and water beetle assemblages, may be readily catered for; others are dependant both on structural aspects of the habitat and on the mobility of individual species, and are far more difficult to accommodate, e.g., invertebrates associated with ancient trees. Historic examples of habitat regeneration are poor models of habitat regeneration on modern arable soils. Considerable changes in soil structure, pH and chemistry have resulted from the introduction of modern soil preparation techniques, fertilisers and pest control. Recent studies also suggest that mycorrhiza are fundamental to establishment of many habitats of conservation interest. Compensatory habitat creation can probably be used in some wetlands and inter-tidal environments, but the prospects for success in many terrestrial situations are far less certain. It therefore follows that compensatory habitat creation (also called “offsets”) cannot be relied upon in all circumstances as means of offsetting loss of the highest quality habitat, and cannot be seen as a consistent and reliable delivery mechanism for sustainable development.