Digistore Resources

Digistore Resources

Digistore Resources North Island Brown Kiwi http://www.tki.org.nz/r/digistore/protected/objects/?id=2455&vers=2.0 Description This image shows a North Island brown kiwi ('Apteryx mantelli') preserved by taxidermy. A flightless bird, it has brown feathers streaked with a reddish tinge. The long thin bill is ivory in colour with nostrils located at the end - a feature unique to the kiwi. The bird here is a male, about 40 cm high, and would have weighed about 2.2 kg. Females generally weigh closer to 2.8 kg. Educational Value This asset is an example of an endangered species included on the IUCN Red List of Threatened Species. Mainland populations of the North Island brown kiwi may have decreased by as much as 86% in 36 years (three bird generations), because of predation and loss of habitat. It is one of five species of kiwi found in New Zealand. The North Island brown kiwi is generally found in the upper parts of New Zealand’s North Island, namely in Northland and the Coromandel Peninsula, where it inhabits dense, subtropical and temperate forests. The male kiwi incubates the newly laid egg for two-to-three months. The female produces one of the proportionally largest eggs of any bird, comprising 15-20 per cent of her body weight. The kiwi is the smallest living member of the ratites, a notable group of flightless birds that have no ridge (keel) on their sternum (breast bone) to which wing muscles would be attached in birds that fly. Kiwis mate for life, keeping in touch with their partners through the loud calls, and are symbols of New Zealand’s national identity. Upland Moa Skeleton http://www.tki.org.nz/r/digistore/protected/objects/?id=2456&vers=2.0 Description This is a complete skeleton of an extinct upland moa ('Megalapteryx didinus'). It was discovered in 1987 in the Oparara Valley, a remote area near Karamea on the northwest coast of New Zealand’s South Island. The moa was a flightless bird, and it is believed this one became trapped in a limestone cave over 15,000 years ago. When alive, this moa stood about 1 metre tall and weighed around 56 kilograms. Educational Value The moa was unique to the high country of the South Island of New Zealand and became extinct mainly through the hunt for food by humans. The moa was a low-slung bird with its head held only slightly above the level of its back - its stance is unlike that of the ostrich species, with which comparisons were made. The moa was a member of the ratites (which include ostrich and emus) - a notable group of early birds that have no ridge (keel) on their sternum (breast bone), to which wing muscles are attached in birds that fly. Moa are thought to have evolved from flying ancestors whose breast muscles and wings degenerated when they increased in size and improved their ability to run. The roof of the limestone cave in which the bones were found had collapsed in several places, creating vertically sided potholes up to 50 metres deep. Once the flightless moa had fallen in, there was no chance for escape. The moa was the tallest of birds known, with some growing up to 4 metres in height. Although the upland moa is one of the smallest moa, it is still larger than most birds alive today. Skulls of Hector’s and Maui’s Dolphins http://www.tki.org.nz/r/digistore/protected/objects/?id=5516&vers=1.0 Description These skulls represent the two recognised subspecies of Hector’s dolphin, a coastal dolphin found only in New Zealand waters. On the right is a skull of a Hector’s dolphin ('Cephalorhynchus hectori hectori’). There appears to be some genetic distinction between this species and the skull on the left, which is that of Maui's dolphin ('Cephalorhynchus hectori maui’). This subspecies of the Hector's dolphin lives off the west coast of the North Island. The skull measures 30.2 cm in length. It is both genetically and physically distinct from the South Island population, the main distinction being size. Maui’s dolphins are slightly larger than South Island Hector’s dolphins. Both skulls have a pointed beak shape. The Hector’s dolphin has close to a full set of teeth, while the Maui’s dolphin has no teeth present. There is a prominent protrusion of bone from the eye sockets on both skulls. Educational Value These skulls are of two subspecies, which are amongst the rarest dolphins in the world. They are members of the 'Delphinidae' family, of which there are 35 species worldwide. The skulls demonstrate the atypical mammalian structure of the dolphin skull, and an evolutionary change that makes it easier for the efficient exchange of air at the sea surface while the animal stays largely submerged. As mammals, dolphins breathe air, and the nasal cavity that leads to the dolphin's blowhole is situated towards the top of the skull. The Hector's dolphin is the only dolphin endemic to New Zealand waters. Genetic analyses show that this dolphin can be broken into four populations. The population of the Maui’s dolphin off the west coast of the North Island is distinct enough to be considered a separate subspecies. The main physical difference is that the Maui’s dolphin is slightly larger and there is also a suggestion of variation in colour pattern, but this requires further investigation. One of the shortest members of the dolphin family, an adult Hector's dolphin grows to a length of about 1.5 m for females, while males are a little smaller. In contrast, Maui’s dolphins may be as long as 1.62 m. Common dolphins reach about 2.6 m in length. The Hector's dolphin also has a distinctive rounded dorsal fin (similar in shape to one of Mickey Mouse’s ears) compared to the usual falcate-shaped dorsal of most other dolphin species found in New Zealand waters. The Hector's dolphin is listed as endangered in the IUCN (the World Conservation Union) Red List of Threatened Species, and the Maui's subspecies is listed as critically endangered. There are only an estimated 3,000-4,000 Hector's dolphins and 75-130 Maui's dolphins remaining. Living close to shore, these dolphins are susceptible to threats from humans and at risk from marine pollution and recreational boating activities, but especially from gillnet fishing. This is an inshore method of fishing involving nets that can be 500 m long. Discarded nets, called 'ghost nets' can float around in the ocean and catch all sorts of wildlife including Hector’s and other small dolphins. Although able to live for up to 20 years, 'Cephalorhynchus hectori’ does not breed very often, only producing one calf every 2-4 years. Hector's and Maui's dolphins do not commence breeding until they are 7-9 years old and the subspecies do not interbreed. This makes the consequences of human activities such as fishing even more devastating. New Zealand’s first marine mammals sanctuary was established for 'Cephalorhynchus hectori’ in 1988 around Banks Peninsula. The sanctuary stopped commercial set netting in an area of 1,170 square kilometres and restricted the use of the area by amateur set netters. In September 2003, commercial set netting was banned from northern Taranaki to Maunganui Bluff on the west coast of the North Island, including inside the heads of the Manakau Harbour to protect the small population of Maui’s dolphins. This dolphin species was named after Sir James Hector, one of the most influential New Zealand scientists of his time. In 1865 he was appointed director of the Geological Survey and Colonial Museum in Wellington and examined the first specimen of the dolphin ever found. Wandering Albatross, 1993 http://www.tki.org.nz/r/digistore/protected/objects/?id=2669&vers=2.0 Description This is a wandering albatross ('Diomedea exulans'), one of the world’s most celebrated birds. The bill is yellow and pink in colour, and the tail is mostly white with black tips. Wandering albatrosses often appear exclusively white from a distance, but usually they are not. There are darker wavy lines on the breast, neck and back, and the wings change colour from black to white with age. This specimen was preserved by taxidermy by Noel Hyde after it was caught on a tuna long line off the East Cape of New Zealand in 1993. Educational Value With a wingspan of up to 3m, the wandering albatross has the largest wingspan of any living bird. They use this enormous wingspan to glide effortlessly on updrafts of wind, and spend most of their life in flight (unlike most other birds). Their body length can be up to 1.35 metres, and females are slightly smaller than males. The wandering albatross may fly thousands of kilometres on a single foraging trip. One bird was recorded as having flown 6,000 kilometres in 12 days. Albatrosses feed in different areas according to their age and sex, the stage in their breeding cycle, and the population they originate from. The albatross is a species in decline. It is slow to breed, and its population has dropped significantly since 1985, mostly as a result of commercial fishing practices. Embroidered Picture of a Huia, c1900 http://www.tki.org.nz/r/digistore/protected/objects/?id=5937&vers=1.0 Description This is an embroidered picture of a female huia bird ('Heteralocha acutirostris') on a branch taking nectar from the flowers of a rata (a native New Zealand tree).

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