The marsh crake (Porzana pusilla affinis), or koitareke as it is known to Maori, is one of the most secretive New Zealand birds, largely because it inhabits dense wetland vegetation, rarely ventures into the open and usually only calls at dusk and through the night.
Quick facts
Marsh crakes are small water birds (15-18 cm, 30-40 g). They are rarely seen and their exact population numbers are unknown.
The crown, upper parts and wings are rich chestnut-brown with flecks and streaks of black and white, the face and under parts are grey with black and white bars towards the flanks and vent. The eye is bright red, the beak green and the legs olive or yellowish-olive. Both sexes have similar plumage although the female is said to be duller. Juveniles are similar but have buff-brown instead of grey underparts.
Little is known of marsh crake behaviour and ecology. They are very secretive and most conspicuous from their calls at night in spring and early summer. Marsh crakes may migrate locally, as other subspecies do overseas.
Marsh crake’s territorial and courtship calls can make them easier to hear in spring, but they generally only call at night. A range of calls includes: “Kreeek”, “Trrrrrrr” (combing), “Krakrakra-gagaga” and “Krehehehe”.
Marsh crakes are monogamous and breeding occurs within dense cover in wetlands. Aerial courtship flights occur at night. Nesting occurs between September and December. The nest cup consists of woven grasses generally concealed under sedges or dense reeds in water. The female lays 5-7 olive-brown eggs. Both sexes incubate and incubation takes 16-20 days. Chicks are covered with black down when they hatch.
Marsh crake primarily feed on invertebrates and seeds of aquatic plants.
They are a potential indicator of wetland health because they are dependent on the presence of high quality and ecologically diverse habitats and rich food supplies.
Similar species: spotless crake (general dark plumage and red eye) and banded rail (much larger) but these are not known to be present in the Whakatipu Area.
Threats
The main threats to marsh crake/koitareke are:
Habitat clearance and drainage has had a significant impact on marsh crake. Over 90% of lowland freshwater wetlands have been drained and cleared for agriculture since Europeans settled New Zealand. Degradation of the remaining wetlands continues with grazing, water pollution and taking of water for other uses being major threats.
Continued habitat modification including the loss of food supplies.
Predation by introduced mammals such as cats, dogs, mustelids and rats. Cats appear to be a significant threat to marsh crake, based on historic and current data.
Other factors which impact on the marsh crake/koitareke:
Road-kills and flying into power lines are also causes of death.
Nesting crakes are sensitive to disturbance by humans.
If you see a marsh crake, please do not disturb it. If you can, take a photo and send it through to us with the location day and time of sighting. This will help us build up information about where they are living.
Volunteers Marty, Liam, Audrey and Dawn monitoring for Crake, July 2023
Thanks to Marty Barwood for the photo!
They respond well to habitat restoration so help out with any projects you can to support these cryptic birds. Please keep dogs on a lead around wetlands.