New Zealand falcon (karearea) as biodiversity and pest control in Marlborough vineyards

Status and Threats

Native New Zealand falcon (karearea) declined due to habitat loss and predation by introduced pests; current wild population estimated at 4000-8000 birds.
Eastern South Island form classified as Nationally Vulnerable in NZ’s threatened-bird categories.
NZ falcon is one of only three birds of prey remaining in NZ; others are the Australasian harrier (kahu) and the morepork (ruru/boobook owl). Endemic raptors like Haast’s eagle, sea eagle, and laughing owl are extinct.
Nesting: nests in shallow ground scrapes (ground cliff ledges/rock overhangs); chicks vulnerable to predation by rats and stoats.

Goal: use falcons as natural pest controllers in Marlborough’s Wairau Plains vineyards; reduce grape damage and provide economic benefits to the wine industry.
Conservation actions: translocation of falcon chicks from surrounding hills since 2005; some birds have paired and are breeding in vineyards.
Nesting enhancements: predator-proof artificial nests; partial-year artificial feeding to support falcon chicks; feeding reduced as grapes ripen to encourage hunting.
Outcomes: falcons have reduced pest-bird presence, lowering grape removals; potential grape-damage reduction > 75\%.
Broader benefits: sustainable biological pest control; reduces need for poisoning, shooting, trapping, netting, and banging; promotes woody habitat conservation; potential for marketing and tourism.
Expansion potential: exploring use in other wine-growing areas (e.g., Central Otago Pinot Noir) and related industries like market gardening and arable farming.

Diet: small birds, rodents, rabbits, and large insects.
Hunting speed: dives at speeds in excess of >200\ \text{km h}^{-1}.
Predation effects: presence and threat of predation alter pest-bird behaviour, reducing grape damage from pest birds.
Native silvereyes (peck grapes) still occur; pecking reduced but fungal infections may persist.

Primary vineyard pests: introduced starling, blackbird, song thrush; native silvereye also pecks grapes.
Grape damage can be as high as 23\%, leading to industry-wide losses of more than 70{,}000{,}000 USD per year.
Falcon presence linked to decreased pest birds and grape removals; potential overall grape damage reduction exceeding 75\%.

Translocation risks: in 2006–07, 15 chicks were released; outcomes included 5 electrocuted, 1 killed by a cat, 1 road-kill.
Mitigation measures: release sites chosen away from electricity poles; ongoing discussions with electricity suppliers to reduce electrocution risk.
Community concerns: falcons can attack domestic poultry; outreach emphasizes benefits and aims to gain broader acceptance.

Reintroduction of a nationally threatened species in a former local-extinction area; supports sustainable pest control and biodiversity without woody-vegetation clearance.
Potential to scale to other wine regions (e.g., Central Otago Pinot Noir) and sectors (market gardening, arable farming).
Tourism and marketing potential linked to the falcons and the Wairau Plains.

Wairau Plains vineyard as an example of predator-precluded grape damage reduction by falcons.
Falcon chicks translocated and reared in vineyard settings with predator-proof nesting.