The swamp harrier (''Circus approximans''), also known as the Australasian marsh harrier, Australasian harrier or swamp-hawk, is a large, slim
bird of prey
Birds of prey or predatory birds, also known as raptors, are hypercarnivorous bird species that actively hunt and feed on other vertebrates (mainly mammals, reptiles and other smaller birds). In addition to speed and strength, these predator ...
widely distributed across
Australasia
Australasia is a region that comprises Australia, New Zealand and some neighbouring islands in the Pacific Ocean. The term is used in a number of different contexts, including geopolitically, physiogeographically, philologically, and ecolo ...
. In
New Zealand
New Zealand ( mi, Aotearoa ) is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and over 700 List of islands of New Zealand, smaller islands. It is the ...
it is also known as the harrier hawk, hawk, or by the
Māori name . Its arrival in New Zealand happened within the last 700 years, replacing its
sister species
In phylogenetics, a sister group or sister taxon, also called an adelphotaxon, comprises the closest relative(s) of another given unit in an evolutionary tree.
Definition
The expression is most easily illustrated by a cladogram:
Taxon A and ...
, the larger extinct New Zealand endemic
Eyles's harrier
Eyles's harrier (''Circus teauteensis'') is an extinct bird of prey which lived in New Zealand. Its closest relative is the smaller Swamp harrier (''Circus approximans''), which arrived in New Zealand after its extinction.
Name
This species was ...
.
The swamp harrier belongs to the sub-family
Circinae and genus ''Circus'', which are represented worldwide, except
Antarctica
Antarctica () is Earth's southernmost and least-populated continent. Situated almost entirely south of the Antarctic Circle and surrounded by the Southern Ocean, it contains the geographic South Pole. Antarctica is the fifth-largest co ...
. The sub-family and genus are derived from the characteristic behaviour of circling flight during courtship and hawking.
Description
The swamp harrier is largely dark brown, becoming lighter with age, and has a distinct white rump. It hunts by flying slowly, low to the ground, on upswept wings. The body length is , and the wingspan is . The recorded weights of adults range from . Females are significantly larger than the males. In
New Zealand
New Zealand ( mi, Aotearoa ) is an island country in the southwestern Pacific Ocean. It consists of two m