Mangere Island
Situated to the West of Pitt Island, Mangere is 113ha in area, surrounded by cliffs and rises to 286m at its summit. It was purchased by the Crown in 1966 after having been farmed, which resulted in the widespread clearance of most of the vegetation. The last sheep were removed in 1968 and the island is now completely free of introduced mammalian herbivores and predators.
Mangere and Little Mangere Island
seen from Rabbit Island
It is mostly covered in rank grass, a legacy of the farming era, but Mangere is now being actively re-vegetated. Thousands of plants are raised each year, planted out and weeded by hand. There is a patch of remnant akeake forest on the north-east side, home to a small but thriving population of black robins. The cliffs and steep slopes support communities of shrub daisies, prostrate Chatham Islands koromiko, iceplant, Chatham Islands geranium and megaherbs such as giant sowthistle and soft speargrass.
Mangere is now one of only two sites in the world where black robin are found. Chatham Islands snipe and parakeets are common. Forbes' parakeet is far rarer than the red-crowned parakeet, being found only on Mangere and Little Mangere. Sea birds, once totally dominant on the island, declined drastically during the farming era, but are making a comeback. Petrel and shearwater burrows are common in places, and the shore platforms are home to Chatham Island oystercatchers. New Zealand shore plover have recently been translocated from Rangatira.
The privately-owned Little Mangere (Tapuaenuku, right in the photo above) lies just off the south-west end of Mangere (centre left). Little Mangere is a towering volcanic massif, 17ha in area and 214m high. It had become the only home of the Chatham Island black robin when the last seven individuals were transferred to Mangere island in the late 1970s, in a last-ditch attempt to save the species. Little Mangere is still an important site for Forbes' parakeet and Chatham Islands button daisy, and supports an active population of sea birds that burrow among the roots of its forest cap. Further to the south-west are The Castle (Rangiwheau) and Sail Rock (far left) two spectacular rock stacks upon which the ocean swells hurl themselves. Sugar Loaf is another stack, off the east of Mangere.