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Extinct is forever Extinct means it’s too late. |
| When a species is extinct, it means that there are no more of the species alive anywhere in the world. Some species may be ‘extinct in the wild’ which means that the only ones alive are kept by people, probably in a zoo. |
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When is extinct, really extinct? People must be careful when declaring a species to be extinct. They need to be certain that all efforts to find the species have been made and that there have not been any sightings for a number of years. There have been cases when people thought a species was extinct – but in fact it was not! A species may have reduced in number due to a poor breeding season or lack of food, or the remaining population may be living in a remote area. Therefore it may not have been spotted for a long time. This may cause people to think the species has become extinct. A good example of this is the takahe. The takahe was thought to be extinct as it had not been seen for 50 years, but Geoffrey Orbell rediscovered the takahe living in a remote Fiordland valley in 1948. (To learn more about the Takahe, read ‘Discovering New Zealand Birds‘ by Sandra Morris and ‘Saving New Zealand’s Endangered Birds’ by Rod Morris and Hal Smith.) |
How many New Zealand birds have become extinct? See the list of extinct New Zealand birds. |
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| Why do species become extinct? The answer to this question is broken up into two parts
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| Extinctions before people arrived in New
Zealand What do we know? Nothing for sure because the extinctions happened before people were around to record it! But scientists have gathered information from fossils and have come up with some answers. They have learnt that a species may have become extinct because of: Environmental changes - the climate or habitat could have changed, causing a lack of food or reduced breeding. Predators and competitors - species may have been killed off by predators or had a hard time finding food because of competition for the same food from other species. Evolution - some species may have evolved (changed) into other species. |
| Extinctions
after people arrived in New Zealand There are three things that people did that caused birds to become extinct in New Zealand:
Most extinctions were not caused by just one of these things, it was usually a combination of these points.
Let’s have a closer look at some of New Zealand’s extinct birds…… |
| The
Laughing Owl The Laughing Owl was given its name because of its call, which sounded like someone laughing. Its Maori name was Whekau. The laughing owl could once be found throughout New Zealand and was twice as big as the native morepork. When Europeans arrived in New Zealand there were only a handful of recorded sightings in the North Island, but the laughing owl was frequently seen in the South Island. The sightings of the laughing owl became very limited after the 1880’s. The last laughing owl recorded was found dead in 1914 in South Canterbury. |
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| Why did the laughing owl become extinct? Nobody knows for sure but it was most likely a combination of events. Laughing owl bones have been found in Maori kitchen middens. Midden sites are places where large amounts of cooking remains are found, they are ancient rubbish tips! Midden sites tell archaeologists a lot about the people who lived in lands before history was written down. If bones of animals are found in kitchen middens it is proof that they were eaten by people. The laughing owl was probably also a victim of the introduced animals. Both Polynesians and Europeans brought animals to New Zealand, such as rats and stoats, that would have killed laughing owls and eaten their eggs and chicks. | |
| The New
Zealand Eagle (Also known as the Giant Eagle and the Haast Eagle) The largest eagle ever known once flew in New Zealand skies - the New Zealand or giant eagle. The giant eagle was endemic to New Zealand, which means it was only found in New Zealand. Its wingspan measured up to three metres and its talons (claws) were about 7.5cm long! |
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| Scientists think that the giant eagle preyed on other birds, including the moa. There have been three complete sets of giant eagle bones found. The set of bones found most recently was in a cave near Nelson in 1989. The youngest set of bones is about 500 years old. Because the giant eagle would have been at the top of the food chain in New Zealand it is most likely that there were never great numbers of this bird. Scientists cannot be sure what caused this giant bird to become extinct but they believe it was a victim of early Polynesian settlers in New Zealand. It may have been hunted and would have suffered from a lack of food to hunt when the moa disappeared. | |
| The Stephens
Island Wren From fossils that have been found around New Zealand, scientists know that the Stephens Island Wren could once be found on the North and South Islands, as well as Stephens Island. However the only European to ever see the Stephens Island wren alive was David Lyall, the lighthouse keeper on Stephens Island in 1894. Stephens Island is the northern-most island in the Marlborough Sounds. The wren was a very tiny bird, about the size of a silvereye – a native species often seen in New Zealand gardens. The wren was flightless and David Lyall described the bird as running about like a mouse. How did the Stephens Island wren become extinct? It was eaten by the lighthouse keeper’s cat! David Lyall reported that his cat had brought him 17 birds, which were all the same species (they were later named the Stephens Island wren). Because the cat was good at hunting and the wren could not fly, the wren became extinct soon after it was discovered. In fact, the Stephens Island wren was discovered and then became extinct within the space of a year – the only bird known to have this happen. In 1895 this article was in the Christchurch Press newspaper: |
| "At a recent meeting of the Ornithologists’ Club in
London, the Hon. W Rothschild, the well-known collector, described this veritable rara
avis, specimens of which he had obtained from Mr Henry Travers of Wellington, who, we
understand, got them from the lighthouse keeper at Stephens Island, who in his turn is
reported to have been indebted to his cat for this remarkable ornithological
‘find’. As to how many specimens Mr Travers, the lighthouse keeper and the cat managed to secure between them we have no information, but there is very good reason to believe that the bird is no longer to be found on this island, as it is not known to exist anywhere else, it has apparently become quite extinct. This is probably a record performance in the way of extermination. The English scientific world will hear almost simultaneously of its discovery and its disappearance, before anything is known of its life-history or its habits." |
| The Bush Wren is also extinct. The last recorded sightings were: Urewera 1955, Nelson Lakes National Park 1968 and Kaimohu Island (off Stewart Island) 1972. There are two wren species still found in New Zealand, the Rock Wren (found in the South Island, in alpine and sub-alpine areas) and the Rifleman (found throughout New Zealand). The Rock Wren is an endangered species. |
