4.4.1 Passive restoration

Passive restoration involves removing or controlling invasive predators and invasive, habitat altering vegetation to allow seabird populations to recover or recolonise sites naturally. This has been the most common management strategy for seabird restoration in the past but is highly dependent on the proximity of the restoration site to source populations or active transit routes. This technique is the least costly, least risky and least time consuming.

For some species it can be highly successful – for example, passive restoration in Maui Nui, Hawaii through predator control and the creation of predator proof fences, has resulted in significant increases in ‘ua’u kani (Wedge-tailed Shearwater) populations within a short time frame. Breeding pairs skyrocketed from zero to several thousand breeding pairs in less than 20 years in three colonies and only slightly less dramatic increases in three other sites.17 However, passive restoration may have a lower success rate than active restoration in other scenarios.