The assessment of restoration of habitat in urban wetlands

Wetlands in urban areas are often restored in an attempt to reduce the loss of such habitats. Unfortunately, the success, or otherwise, of programmes of restoration has rarely been systematically gauged. Through not knowing whether programmes of restoration are successful or not, valuable resources potentially continue to be wasted, wetland habitats remain degraded and the methods of restoration are not assessed for future programmes of restoration. Several factors have contributed to poor assessment of restoration of urban wetlands. First, often the goals of restoration have been unrealistic because they failed to consider that wetlands in urban areas are subjected to ongoing and often largescale anthropogenic disturbances. Second, goals of restoration often have nor been clearly defined and, consequently, predictive hypotheses were not formulated to test for the success of restoration. Third, even when success of restoration has been assessed, this has not always been adequate because of inappropriate sampling design. Such problems can be overcome by treating restoration of habitat as experiments and using the knowledge gained from each project to improve future programmes of restoration. This will ensure that the remaining semi-natural habitats along coasts in urban areas can be more effectively managed. (C) 1999 Elsevier Science B.V. All rights reserved.