How Good Design Can Protect the kārearea (New Zealand Falcon) and Improve Network Safety

Rob Douglas - Energyedge Limited

Dr Laurence Barea - Department of Conservation

Ed Waite - Department of Conservation

Chris Hankin - Department of Conservation

The kārearea or New Zealand Falcon (Falco novaeseelandiae) is the country’s most threatened bird of prey with only around 3000-5000 breeding pairs remaining. A recent five year study in Marlborough and observations in Otago have attributed nearly half of all falcon deaths to electrocution. This paper looks at the extent of the known electrocution problem across New Zealand and the studies, programmes and collaborations that have been undertaken to monitor and mitigate the issue. It uses examples of where birds have interacted with lines and equipment, to show the consequences and mechanisms by which bird deaths have occurred and the attendant public hazards through earth faults and transferred potentials. Falcon deaths in the Otago region have been linked to inline structures as well as those with transformers and high voltage cable terminations. It is therefore important to ensure that all structures are designed sympathetically. Good ‘Falcon Friendly’ design is an excellent proxy to use to help reduce other wildlife contact in general. Other New Zealand species known to be susceptible to electrocution include Harrier, Kereru, Kaka and the White Faced Heron, although kārearea appear to be most at risk. This paper looks at the current collaboration between Aurora Energy Limited (the electricity network) / Delta Utility Services Limited (its principal contractor) and the Department of Conservation and acknowledges the work done by Marlborough Lines. The retrofitting of covers onto assets can reduce or eliminate raptor electrocution but is expensive, resource intensive and leads to enduring maintenance costs. Large scale pole replacement programmes provide cost-effective opportunities to fundamentally change overhead design to give improved outcomes for wildlife, networks and people. From video footage of falcons nesting near Wanaka and mock-ups of cross arms and assets, this paper documents some typical Falcon behaviour that we have seen, and outlines the preliminary critical geometries, layouts and separations that need to be considered to avoid and mitigate adverse outcomes.