Auckland Museum's experts get you closer to the natural world in your backyard, beach or bush with our five-part series. Today, we focus on birds with curator of land vertebrates Brian Gill.
KEY POINTS:
Birds have fascinated humans for thousands of years - we watch them, we paint them and we keep them as pets.
Prior to the arrival of man, New Zealand was a paradise for birds.
With few predators they thrived, and some gradually lost their wings as they did not need to fly to escape.
Some grew very large and began nesting on the ground.
Traditionally, we thought that when New Zealand broke away from Gondwana, mammals (predators of birds) had not spread here, making our islands welcoming for birds.
This idea has recently been challenged, as some small mammal bones have been discovered which are dated at approximately 18 million years old.
Therefore, mammals lived here, but may not have been serious predators.
Darwin looked at finches when he was at the Galapagos Islands.
He noticed that there were different kinds of finches living in different habitats on different islands.
We can see a similar case with New Zealand birds such as the kokako, saddleback and huia, which are from the same family but show different size and beak-shape because they have evolved to survive in their environment in different ways.
Our search
We're looking for three types of bird: please feel free to either draw or photograph them.
Red-billed gull, tarapunga (larus novaehollandiae)
Small seagull with grey back and white head and underparts. This is how you can identify them: About 40 cm long. Beak and legs bright red in adults (dull reddish-brown in juveniles). The smaller of our two common gulls. Noisy and quarrelsome. Often in small groups or large flocks. Found everywhere on the Auckland foreshore; easily attracted with food.
The red-billed gull is a generalised scavenger of the coastal zone; able to quickly locate opportunistic food-sources and cope with eating a wide variety of foods.
They breed together in large colonies and their droppings represent a big transfer of nutrients from the marine ecosystem to land.
Pied shag, karuhiruhi (phalacrocorax varius)
Large shag about 80cm long with a long, slender beak. This is how you can identify them: Glossy black above and on thighs.Face and all underparts white. Bill grey-pink. Immature birds have the black areas replaced by brown. Dives underwater to catch fish. On land they may hold out their wings to dry. Roost and nest in large trees near the shore. Common in the Auckland area.
The pied shag has a long, powerful beak ending in a slight hook that is specially adapted to seizing fish; they do this underwater where they propel themselves by their strong feet which have a web between all four toes.
Tui (prosthemadera novaeseelandiae)
Large songbird about 30cm long with a pointed beak. Looks black in dull light, but some feathers are shiny dark green. White bar on the wings and two white throat tufts (pois). Feeds in trees on insects, berries and nectar.
* An energetic and acrobatic feeder. Noisy whirring flight.
* Loud melodious song mixed with harsh sounds.
* Common in the Auckland area.
The tui is a generalised insect and berry-eater, but also specialised as a nectar-feeder by having a brush-tipped tongue that helps draw nectar out of flowers by capillary action.
They play an important role in the bush by transferring pollen between flowers and spreading the seeds of native trees with small berries.
Cultural significance
All three birds are not endangered and are quite common.
Tui feathers were used by Maori as a material in their traditional cloaks (korowai). Red-billed gulls were believed by Maori to carry the souls of the dead, and tradition has forbade the hunting of them.
Their future
Gulls are under no obvious threats; their breeding colonies are often on islands or relatively safe headlands and they will mob predators at the colonies.
The pied shag's breeding colonies in trees are pretty safe from predators, but they are threatened by coastal development and oil spills and may be accidentally killed in fishing nets. The tui's breeding success has been dented by introduced mammalian predators such as rats and stoats.
To learn more about these three birds, the museum has plenty of information in the Learning Centre as well as a beautiful Maori cloak made of tui feathers for people to view.
LIFE'S CUTTING EDGE
Biology gripped Brian Gill at university in the 1970s, when he studied zoology.
"There was the sense that this was part of the cutting edge of new knowledge," he says. "There was probing and dissection, and the detached, analytical scientific approach. Despite this (and also because of it), the wonder shone through of living things in all their complexity and diversity."
* Illustrations from Powell's Native Animals of New Zealand, published by Auckland Museum.
