Ecological Corridors

Ecological Corridors

A research report published by Kerry Lukies on behalf of the Eastern Bays Songbird Project

Executive summary

The Auckland Council commissioned this research report to identify strategic revegetation sites in the Eastern Bays in order to increase indigenous forest cover, improve the long-term viability of current ecosystems and restore ecological corridors to enable movement of native species throughout the Eastern Bays. While written as an ecological report, it aims to be accessible to a range of readers with little scientific knowledge. The report focussed on private land and transport corridors as both public and Māori land in the Eastern Bays already have comprehensive revegetation strategies in place.

The biodiversity decline driven by habitat loss and introduced mammalian predators results in many native birds, insects and reptiles being confined to pest-free offshore islands, such as those in Auckland’s Hauraki Gulf. The pest control efforts by the Eastern Bays Songbird Project suggests that the Eastern Bays can become a safe landing area for native birds returning to mainland Auckland from these pest-free islands. While large areas of green space in the Eastern Bays provide some habitat for native species, ecological corridors between these forested fragments will increase the overall size of available habitat and ensure that birds, along with reptiles and insects, can migrate, disperse and repopulate areas not otherwise used. Reconstructing native habitat through increased planting and establishing connectivity between habitat patches ensures that native species can move freely through modified urban ecosystems such as the Eastern Bays.

Methods used in this report included interviews with members of the local community, consultations with ecologists and desk-based research to determine which native species would be most suitable for the Eastern Bays, how existing forest fragments and corridors could be enhanced, and where new ecological corridors would be most appropriate. Existing forest fragments and corridors, along with proposed corridors for revegetation were outlined on maps of the Eastern Bays Songbird Project zone.

Retaining existing vegetation, removing weeds and competitive exotics and increasing canopy cover on both public and private land were identified as key measures to increase and enhance habitat for native biodiversity in the Eastern Bays. A diverse assemblage of native groundcovers, shrubs and trees were suggested for revegetating backyards and transport corridors in key zones as defined in this report. Enhancing transport corridors and backyards with native vegetation would significantly increase indigenous forest cover, enhance connectivity between forest fragments and help to create a pest-free urban sanctuary where populations of native species can flourish. Revegetation efforts in the Eastern Bays would also be a critical step towards facilitating the movement of biodiversity throughout the area and the wider Auckland region.