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  1. Species
  2. ›
  3. Accipitridae
  4. ›
  5. Circus
  6. ›
  7. Swamp Harrier
Swamp Harrier
Photo · (c) Jan Ebr & Ivana Ebrová, some rights reserved (CC BY)

BirdUp · Species

Swamp Harrier

Circus approximansPeale, 1848

Updated 21 March 2026

Also known asKāhu

Conservation status: Least ConcernOrigin: Native
Order
ACCIPITRIFORMES
Family
Accipitridae
Genus
Circus

At a glance

The Swamp Harrier is a large bird, about 50–60 cm long, listed as Least Concern and native to Australia. It can be seen year-round.

Size
50–60 cm
Conservation status
Least Concern
Origin
Native
Best seen
Year-round
Commonness
Very common
  • Identification
  • Where
  • When
  • Behaviour
  • Gallery

01 · Identification

How to tell it apart

What does a Swamp Harrier look like?

The Swamp Harrier is a large bird, about 50–60 cm long and weighing 520–1080 g.

The swamp harrier, also known as the Australasian marsh harrier or Australasian harrier, is a large, slim bird of prey widely distributed across Australasia. In New Zealand, it is also known by the Māori name kāhu. It arrived in New Zealand within the last 700 years, replacing the larger species, the extinct New Zealand endemic Eyles's harrier.

Description · wikipedia · CC BY-SA 4.0

Field specs

Length
50–60 cm
Weight
520–1080 g
Wingspan
118 cm

Measurements · avonet · CC BY 4.0

03 · When

When to look

When can you see a Swamp Harrier?

The Swamp Harrier is present across its Australian range year-round, so it can be seen in any month.

  1. Jan
  2. Feb
  3. Mar
  4. Apr
  5. May
  6. Jun
  7. Jul
  8. Aug
  9. Sep
  10. Oct
  11. Nov
  12. Dec

05 · Behaviour

Habits and haunts

What does a Swamp Harrier eat?

The Swamp Harrier feeds on terrestrial vertebrates and carrion, usually foraging in flocks or alone.

06 · Gallery

Plumage up close

4 photos

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02 · Where

Where to find it

Where does the Swamp Harrier live in Australia?

The Swamp Harrier is native to Australia, recorded across 88 of Australia’s bioregions.

BreedingAustralia (except south-central), North, South, Stewart and Chatham is. (east of South I.; New Zealand), Vanuatu, New Caledonia including Loyalty Is., to Fiji and Tonga (south-west and south-central Polynesia)

Non-breedingTo Trans-Fly (south-central New Guinea) and Kermadec Is. (north-east of North I., New Zealand)

Distribution from BirdUp Australia community data

Legend

  • Resident

8 regions recorded