On the 9th of March a spotless crake (Porzana tabuensis plumbea), or pūweto as it is known to Māori, was discovered by the Hunt family in Ohau River. The crake was waterlogged and trying to climb the bank. The Hunt family rescued the bird and brought it to Ngā Manu. Since opening in 1981, Ngā Manu has only had 2 spotless crake brought in to us for rehabilitation, so staff were understandably excited when this one arrived. Spotless crake have declined dramatically since humans began draining wetlands and are now classed as at risk relict. The number of spotless crake in New Zealand is unknown. Although waterlogged, this crake brought in by the Hunt family was in good condition.
Once the crake was dried out and well fed on insects, it was ready to be released. Our supervisor Rhys Mills and Anne Cheater (one of our volunteers) released the crake on the 11th of March in our lookout board walk area, typical crake habitat and an area where other crake have previously been heard. The crake soon disappeared from sight.
The spotless crake is rarely seen as it is a secretive bird, living in freshwater wetlands throughout North Island and much of South Island. There are known populations that seasonally inhabit Ngā Manu, but their furtive nature and good dispersal ability make them very hard to spot. They are heard more often than seen. Several different calls are given, including bubbling sounds, a short ‘pit-pit’, a repeated ‘mook’ and the loudest call, a long trilling ‘purr’.
The spotless crake is a small dark rail, about half the size of a common blackbird. The plumage is dark brown on the upper parts and dark bluish grey beneath. They have a stout, black bill, orange-pink legs and their bright red eyes contrast sharply with the dark head. Juveniles are duller with a pale chin and throat and dark legs. They have a broad omnivorous diet, feeding on seeds, fruit and leaves of aquatic plants, and a wide variety of invertebrates including worms, snails, spiders, beetles and other insects.
Spotless crake are monogamous and territorial. When nesting in wetlands, the nest of woven grass and sedge leaves is raised 30 to 50 cm above water level. Several nest-like platforms are often built near the actual nest. The clutch of 2 to 5 cream coloured eggs is laid from late August to January and incubated by both parents for 20 to 22 days. The chicks remain in the nest for up to 4 days and are cared for by both parents for 4 to 5 months. Chicks are capable of catching live prey from 3 days old.
It is wonderful that Ngā Manu provides a habitat for spotless crake as the birds 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.
Blog written by Sarah Fields (Ngā Manu Administration and Marketing Officer).
Images by: Rhys Mills (Ngā Manu Supervisor).