Kaldor, B. (2019, September). Bird disturbance from human activity: Potential effects from recreational activities on sea and shore birds. Avon-Heathcote Estuary Ihutai Trust. 

The Avon-Heathcote Ihutai estuary remains an important cultural, recreational, and ecological site in Christchurch, despite its dramatic degradation over the years. However, the Estuary Trust has become increasingly concerned about increased pressure for recreational access to estuary margins. The purpose of this report, written by Bonnie Kaldor and commissioned by the Estuary Trust in 2019, was to summarise relevant research showing the effects or non-effects of human recreation on birds, to analyse relevant examples of wetland reserves excluded from human use, and examine how New Zealand wildlife refuge legislation and regulations could apply to endangered bird disturbance along the Ihutai edge.

The report confirmed that repeated human, vehicle, or dog disturbance can result in changed behaviour or permanent emigration of birds from an area. Larger disturbances had greater effects on birds and responses tended to be species-specific, however, even small disturbances had the potential to increase vigilance and reduce feeding activity in birds.

Following these findings, the Estuary Trust concluded that increased access to the western Ihutai estuary edge due to new walkways or cycleways would likely have negative effects on many endangered shore birds. Consequently, they emphasised that the legislated Wildlife Reserve along the estuary’s western edge should continue to be treated as a bird sanctuary, and that the Trust will continue to resist moves to open this area to mass recreation.