The Black Robin, or karure, is a small all-black songbird found only on the Chatham Islands east of mainland New Zealand. It is famous far beyond its size for one of the most remarkable conservation rescues ever achieved. By 1980 the entire species had crashed to just five individuals surviving on a single rocky islet, with only one fertile female, later nicknamed Old Blue. Every Black Robin alive today descends from her.
Under conservationist Don Merton, wildlife staff boosted the birds' output by removing early clutches and cross-fostering the eggs to Chatham Island tomtits, prompting the robins to lay again. The population climbed from five birds into the hundreds. Because the entire species passed through such a tight genetic bottleneck, it is often described as one of the most inbred birds in the world, yet it continues to hold on.
The Black Robin is an unassuming small bird with entirely sooty-black plumage, a slender dark bill and long dark legs. It has an upright, alert posture and often perches low, watching the ground before dropping to seize prey. There is little visible difference between the sexes.
| Size | Small, about 15 cm long |
| Plumage | Uniformly dull black over the whole body |
| Bill | Slender, dark and fine, suited to picking invertebrates |
| Legs | Long and dark, often used to hop and stand tall on the forest floor |
| Sexes | Very similar; males average slightly larger |
| Behaviour | Tame and inquisitive, perching low and pouncing on prey |
The male Black Robin sings a simple, quiet warbled song used to hold territory and keep contact with its mate. Both sexes give soft call notes. The voice is unobtrusive and easily overlooked, in keeping with the bird's confiding, low-key manner in the dense island scrub it inhabits.
The Black Robin is endemic to the Chatham Islands. After being reduced to Little Mangere Island, the surviving birds were moved to Mangere Island and later to South East Island (Rangatira), where the main populations now live in forest and dense low scrub. It is entirely dependent on a few small, predator-free islands managed for its survival.
Black Robins are insectivores that forage mainly on the forest floor and among low branches. They take a range of invertebrates including beetles, spiders, caterpillars, cockroaches, wetas and grubs, typically watching from a low perch and dropping to snatch prey from the leaf litter. They will also glean small items from foliage and bark.
Pairs build a cup-shaped nest of twigs, rootlets and moss placed in a tree cavity or within dense vines, usually within about two metres of the ground. The clutch is normally two eggs, occasionally one to three. Only the female incubates, while both parents feed the chicks. During the rescue programme, first clutches were deliberately removed and fostered to tomtits so the robins would re-lay, sharply increasing the number of young raised each year.
- Chatham Island Tomtit: Shares the same islands and served as foster parent; smaller with pale underparts, not all-black
- New Zealand Robin: Mainland relative with dark grey upperparts and a paler belly rather than uniform black
- Tomtit: Closely related small perching bird with contrasting black-and-white or yellow plumage
Why is the Black Robin so famous?
It recovered from just five surviving birds in 1980, with every living Black Robin descended from a single fertile female called Old Blue, making it one of conservation's greatest rescues.
Where does the Black Robin live?
It is found only on a few small predator-free islands in the Chatham Islands of New Zealand, chiefly Mangere Island and South East Island (Rangatira).
What is cross-fostering?
Conservationists removed the robins' first clutches and placed the eggs in the nests of Chatham Island tomtits to raise, which prompted the robins to lay again and greatly increased the number of chicks produced.
Is the Black Robin still endangered?
Yes. Although numbers have risen into the hundreds, the species remains Endangered because of its tiny range and extremely low genetic diversity.