Phoenix Group

Evolutionary Ecology & Genetics

Kārearea – New Zealand Falcon

Falco novaeseelandiae

  • Endemic to New Zealand
  • Found throughout the country except north of Auckland, but including the subantarctic Auckland Islands.
  • Population unknown, last estimate by Fox of 3000-4000 pairs and declining.
  • Female kārearea are up to a third larger than males.
  • Nest on ground or in epiphytes in trees. Up to 4 eggs are produced but usually 2-3 chicks fledge.
  • Prey items include small birds, rodents, rabbits, hares, skinks and insects.
  • Recent research has found kārearea will take prey that is most abundant. In most parts on New Zealand this will be small introduced European birds such as sparrows and finches.
  • Fiercely territorial birds; they defend nests against anything, even helicopters.
  • Three races are currently recognized- Bush, Eastern & Southern. These differ in habitat, body size (approx up to 100g difference in weights between bush and eastern), hunting behaviour and some prey items.

 

falcon in treehead of falcon chickfalcon

Although currently defined as a single species, three distinct races are generally recognised. These are usually referred to as the Bush, Eastern and Southern and considered to differ morphologically and ecologically as well as in their spatial distribution . However, there is uncertainty about precise geographic boundaries of the three races and correlation of morphology, ecology and behaviour. Bush and Eastern falcons are considered to have ranges that meet or overlap in northern and western South Island, suggesting that they are not spatially isolated.
Bush- North Island and North West coast of South Island.falcon map
Smaller and lives almost entirely in bush or pine forest. Adapted to hunting within trees, with smaller size. Nest on ground or in epiphytes.
Eastern- rest of south Island except Fiordland
Is a larger bird which lives more in open habitat such as high country farms, where it takes a lot more mammal prey such as rabbits. It nests on the ground, under logs or on rocky bluffs/cliffs.
Southern- Fiordland and Auckland Islands. A proposed intermediate form of other two, but most similar to bush falcon.


falcon eggsfalcon hatchling

falcon phylogeny

Fuchs et al. (2015) recently showed that, amongst all living falcons, the Kārearea is most closely related to the aplomado falcon of South America. They shared a common ancestor that probably existed about 2.5 million years ago (see right).

Even though New Zealand is about 1500 km from Australia, and much further from South America, falcons have clearly been good at travelling around the world. The young history of this raptor in New Zealand is consistent with the recent arrival of Australasian marsh harrier (Circus approximans), and estimated Pleistocene origin of the now extinct giant New Zealand eagle (Hieraaetus moorei), which is closely related to species including the Australian little eagle (Hieraaetus morphnoides).

 

 

 

 

 

 

Our current research on Kārearea – NZ Falcons

 

 

From Fuchs, J., Johnson, J. A. & Mindell, D. P. (2015) Rapid diversification of falcons (Aves: Falconidae) due to expansion of open habitats in the Late Miocene. Molecular Phylogenetics and Evolution. 82 :166–182.