Distinguishing among remediation, reclamation, and offsetting in the pursuit of no net loss.

The mitigation hierarchy (avoid - minimize - remediate - offset) is a well-accepted framework for prioritizing impact mitigation measures. The roles of three kinds of habitat remediation are sometimes confused. Here we set out to distinguish among and compare "third step remediation" (3SR), the third step in the mitigation hierarchy, end-of-project reclamation/rehabilitation, and offsetting. The essential criteria for 3SR to contribute to no net loss of biodiversity are quality, quantity and timeliness, the last emphasizing the need to address biodiversity losses in a compressed timeframe. Using these criteria, we distinguish 3SR from end-of-project rehabilitation/reclamation and from biodiversity offsetting, the fourth step of the mitigation hierarchy, and offsetting from end-of-project work. We briefly review two policies from Canada and Australia which unhelpfully blur these distinctions. We seek to provide greater clarity to assist all forms of mitigation measures to contribute optimally to the conservation of biodiversity.