Tuesday, April 10, 2012

Magpies


I have had a magpie, the Australian magpie, in the back yard recently, turning over my dog's bones to see if there is any meat left on them. I also see them in the Park occasionally and on the outskirts of town. Another much maligned bird I think. Would that we were not always finding some reason for persecuting and killing birds.


The bell magpie, Gymnorhina tibicen, was brought to New Zealand by the Acclimatisation Societies to control pasture pests and was protected until 1951. Two sub species brought here were the white-backed magpie of Southeastern Australia and Tasmania and the black–backed from northern Australia and New Guinea. In New Zealand the white–backed predominates except in the Hawke’s Bay and in North Canterbury. Like other Australian introductions, the original birds have undoubtedly been supplemented by other birds coming across the Tasman of their own accord, so technically, magpies could be deemed native birds.

I think a lot of their bad press comes from people mistaking them for the Euopean magpie, a quite different character. In the 1990s a vociferous campaign was launched against the magpie but after some complaints from defenders of the magpie, research was iniated by Landcare which came to the conclusion that magpies are not a real threat to native birds. The only native bird they give a hard time is Kahu, the harrier hawk, which is notorious for ransacking nests and does not distinguish between native and introduced.

However, aggression towards people is another matter. For most of the year magpies are not aggressive, but for four to six weeks during nesting they will often defend their territory vigorously. People walking past may be seen as ‘invaders’ of the territory, prompting the magpies to fly low and fast over the person clacking their bills as they pass overhead.

The experience of a magpie attack can be quite alarming, but it is usually only a warning. Only occasionally will a bird actually strike the intruder on the head with its beak or claws. If this unusual behaviour persists, there are ways of reducing the risk of physical injury to humans.

If a magpie swoops at you, walk quickly and carefully away from the area, and avoid walking there when magpies are swooping. Make a temporary sign to warn other people. Magpies are less likely to swoop if you look at them. Try to keep an eye on the magpie, at the same time walking carefully away. Alternatively, you can draw or sew a pair of eyes onto the back of a hat, and wear it when walking through the area. You can also try wearing your sunglasses on the back of your head. Wear a bicycle or skateboard helmet. Any sort of hat, even a hat made from an ice cream container or cardboard box, will help protect you. Carry an open umbrella, or a stick or small branch, above your head but do not swing it at the magpie, as this will only provoke it to attack. If you are riding a bicycle when the magpie swoops, get off the bicycle and wheel it quickly through the area. Your bicycle helmet will protect your head, and you can attach a tall red safety flag to your bicycle or hold a stick or branch as a deterrent.

Friday, December 16, 2011

Blackbirds


Walking my dog today, I noticed that a few of the feijoas are flowering. The feijoas made me think of blackbirds, oddly enough.

The adult male blackbird is black, very black with blackish-brown legs, a yellow eye-ring and an orange-yellow bill. The adult female is in contrast is a sorry brown with a dull yellowish-brownish bill. The juvenile, is similar to the female, but has pale spots on the upperparts, and a speckled breast and are often mistaken for the song thrush. As the young birds mature, they may be seen with patches of black and brown. There are a lot around at this time of year, whistling in the undergrowth, hoping their parents will continue to feed them.


Unlike the thrush which sings through the winter, the blackbird remains silent until the spring when it becomes an annual competion among birders to record the first blackbird singing. The song usually ceases in December but has been heard as late as February. The blackbird's song is very much the largest part of the dawn chorus here in town and far out numbers the Tui's. Last summer there was a blackbird which persisted in singing at night on top of the old council building acoss the road, something to do with the street lighting, I suppose.


Ornitholigists have noted that birdsong uses the same musical scales as we do. Certainly many composers and poets have taken a great deal fom birdsong. Mozart had his pet starling and Beethoven his blackbird, which may be heard in the opening rondo of Beethoven's violin concerto in D, Opus 61. In many species it appears that although the basic song is the same for all members of the species, young birds learn some details of their songs from their fathers, and these variations build up over generations to form dialects. Living in towns and cities birds pick up other sounds as well and may incorporate them into their songs.

But I digress. I started out talking of feijoas which in their native South America are pollinated by birds. The blackbird, together with the myna, have learned the trick of pollinating them in New Zealand. Small birds, such as white-eyes, visit feijoa flowers but research here has revealed that they are ineffective pollinators.

I used to watch blackbirds from the kitchen window on my farm in the Bay of Plenty take apart the feijoa flowers, feeding on the sweet and juicy petals of the brightly coloured flowers, but have never seen them perform the same trick here. My blackbirds here seem to prefer cherries and grapes, while the feijoas languish and produce very little fruit. I'm curious to know whether or not anyone has observed them pollinating feijoas here.

Thursday, November 03, 2011

Dunnock

The dunnock, or house sparrow as some call it, is one of those LBJs as birders call them, “little brown jobs”, drab insigificant birds that are so easily overlooked and mistaken for sparrows. In point of fact, they belong to quite different families, dunnocks are accentors and sparrows are weavers. For the very observant, there are a good many of them in Greytown.

The dunnock is quiet in colour and in manner, unobtrusive rather than shy and will quietly scout about the driveway or under the bushes while I observe it, taking quick peeks at me, just to see what I am about. They have their own special character.

Their bodies are slate grey, streaked with a reddish brown, the deep brown upper mantle streaked black with a slate grey throat and chest and paler lightly striped under parts. They have a fine pointed black bill, unlike the sparrow, for catching insects. They sing in a neat precise manner, as if repeating something learnt by heart.

Their natural breeding range is Europe and western Asia. Several hundred birds were introduced here in New Zealand by the Acclimatisation Societies and private individuals between the 1860 and 1880s.

The Dunnock exhibits mating diversity comparable to that of humans: there are monogamous pairs, polyandrous females with their mates, polygynous males with their mates, and polygynandrous groups of males and females, each of whom has multiple mates. Polyandry is rare in birds, with only about 2% of species showing such a mating system.

The hen, apparently with some help from the cock builds the nest which is well concealed in thick undergrowth or a hedge, normally very close to the ground. It is a neat bowl of twigs, grass and moss lined with hair, feathers and moss.

The diet is mainly small invertebrates, beetles, spiders, flies, aphids, ants and worms. Some small fruits and seeds are also eaten. Most food is taken from the ground, usually not far away from cover.

In spite of being such nondescript birds, they are birds that have gained a lot of attention by people who matter. The famous eighteenth century naturalist, Gilbert White of Selbourne, thought them fine birds but called them hedge sparrows. He observed that they have a remarkable flirt with their wings in breeding time and as soon as frosty mornings come they make a very plaintive piping noise.

Emily Bronte knew the bird by the name dunnock and also knew that it is frequently a foster–parent of a cuckoo. In Wuthering Heights Ellen Dean is asked what she knows of the history of Heathcliff. She replies, “It’s a cuckoo’s, sir... and Hareton has been caste out like an unfledged dunnock”.

The cuckoos in Europe do indeed make shameless use of them but if our cuckoos do the same to them here, there seems to be no record, nor much interest as they are introduced birds..




Wednesday, September 14, 2011

Korimako, the bellbird


I often hear a bellbird calling along Udy Street. Often heard but seldom seen as their discreet colouring makes them difficult to pick out of the background greens.
There are just a few bellbirds in Greytown I think, or else they make themselves scarce in the face of the dominant and aggressive Tuis. Of our two more conspicuous honey eaters, the Tui seems to be dominant in the North Island and the bellbird in the South. A few years ago I spent Xmas at Akaroa and there the bellbird was everywhere, including clamorous and numerous juveniles, but not a Tui in sight.

According to the ornithologist, W. H. Oliver, the bellbird was undoubtedly the chief performer in the chorus described by Joseph Banks when Captain Cook entered Queen Charlotte Sound during the first voyage of discovery. “I was awakened by the singing of the birds ashore, from whence we are distant not a quarter of a mile. Their numbers were certainly very great. They seemed to strain their throats with emulation, and made, perhaps, the most melodious wild music I have ever heard, almost imitating small bells, but with the most tunable silver imaginable, to which, may be, the distance was no small addition.”

The impact of the European on the bellbird at first took the form of a rapid and alarming reduction in the number of birds, especially in the cleared portions of the country but also decreases took place in forested districts. The disappearance was most noticeable in the North Island and large areas are still without bellbirds. In 1873 Buller prophesized extinction for the bird but by the turn of the century it had started to make a modest comeback and followed the tui into our suburban gardens, much to everyone’s delight.

They are tenacious defenders of their nests and the female will physically attack an intruder. She has been known to fall to the ground and flap away to distract a predator. They are territorial during breeding season but after breeding they are usually nomadic and solitary moving around to food sources. They are strictly monogamous and pairs remain together for several years. They court in winter when the male sings in front of the female. After mating they often duet.

“Ka rite ki te kopara e ko nei I te ata” — like the bellbird singing in the morning — was a simile used by Maori orators. Korimako and Makomako are just two of the 26 names Maori had for the bellbird.





Friday, August 12, 2011

Prions


More than a week of severe storms blowing up from the Antarctic has left thousands of sea birds wrecked across New Zealand, not just along the coast but well inland. A local landowner brought in a bird for me this morning, wanting me to help indentify it. After much measuring of the dead bird and consulting of the identification guides, we determined quite confidently that it was a broad-billed prion, and not an antarctic prion which were being reported as being wrecked in large numbers in and around Wellington. The local bird rescuer, the reverend Robin List, confirmed that all the birds he had coming in from around the Wairarapa were broad-billed.

A wreck is when very large numbers of seabirds die and become wrecked around the coast. Sometimes it involves mainly one species, or at other times several species. Some wrecks seem to be caused by storms catching young birds a few days after leaving their nests, others by storms combined with a food shortage. Birds found dead or dying on the beaches are usually only a small fraction of what is occurring at sea. New Zealand lies in the path of seabirds moving eastward in winter from the southern Atlantic and Indian Oceans. Wrecks of 13,000 prions that came ashore in New Zealand during June and July 1964 showed obvious signs of starvation as did a wreck of prions that occurred in 1981 in South Africa and in Chile in 2007. Analysis of dead birds washed up on the world's coasts remains one of the main ways of studying seabird movements throughout the year. The El Nino/Southern Oscillation, a warm water Equatorial current that irregularly flows south along the Chilean and Peruvian coasts is well known to disrupt marine and terrestrial ecosystems and to raise havoc among some seabird populations.

Prions are small birds with blue-grey colouring. The broad-billed prion is characterised by its large broad bill and is found throughout oceans and coastal areas in the Southern Hemisphere. Its colonies can be found on many islands around the coast of New Zealand, in Fiordland, Solander Islands, Foveaux Strait, the Chatham Islands and sub-Antarctic Antipodes Islands. It is probably from these colonies that maybe up to 500,000 birds have been lost, the largest wreck ever recorded.

The broad-billed prion was observed off the East Cape in 1769 during Cook's first voyage and again at Dusky Sound in 1773 by Forster, during Cook's second voyage.

The broad-billed prions diet consists mainly of planktonic crustaceans, but, like other Antarctic prions, it uses its special bill to filter this food from the water. The bill has comb-like fringes called lamellae, similar in principle to the filter plates of baleen whales. It feeds by running across the ocean surface with its bill open under water, moving its head from side to side and skimming for food.

Breeding begins on the coastal slopes of the breeding islands in July or August. The parents incubate the egg for 50 days, and then spend another 50 days raising the chick. Colonies disperse from December onwards.

The prions belong to the Procellariiformes, which were formerly called Tubinares, or tubenoses, and now are generally called petrels. They are almost exclusively pelagic and have a cosmopolitan distribution across the world's oceans, with the highest diversity being around New Zealand.

Procellariiformes have an enlarged nasal gland at the base of the bill, above they eyes. This gland rids the birds of the salt they ingest from sea water.

Spur-winged Plover


Walking along North Street with my dog, always there are spur-winged plovers to be seen in the paddocks. There used to be two or three pairs but this winter I see just the one pair. I hope this is not a trend!



Travelling throughout New Zealand, especially through farmland, the one bird that one is most likely to see is the spur–winged plover, very often being harried by and, in turn, harrying a harrier hawk. However, spur-winged plovers did not used to be so widespread, the first pair recorded breeding at Invercargill airport in 1932. In spite of the heavy predation of their chicks by harrier hawks and our national propensity for using birds for target practice, their numbers have now become so great that there is talk of culling them. Not a good reason, I would think.

There are two well marked races of this bird; the smaller race, Vanellus miles novaehollandiae, originally just bred in the south–east of Australia but then extended its range to Tasmania and New Zealand. The other, northern, race, Vanellus miles miles, has extended its range from northern Australia to New Guinea.

Both races frequent wet grasslands but will readily adapt to man–made habitats such as pastures, sports grounds, airfields and even median strips on busy roads. Indeed, one will often see them on median strips while driving to Wellington. Somehow they seem to have worked out that their chicks will be safe there from cats and harrier hawks. Their liking for airports however, is not a good idea as it leaves them open to some severe culling because of the fear of bird strike.

This large plover has a black crown, hind neck and shoulders, with the back and wings brown in colour. The underparts are white and the legs and feet are reddish. The bill is yellow and the bird has a yellow facial patch and prominent wattles. It has spurs on its wings.

The spur–winged plover feeds mainly on insects, worms and similar small invertebrates but will also eat seeds. Their main call is a loud, penetrating rattle, often heard at night which may explain why many people have grown to hate them.

Breeding is between June and late November with the peak in August. Several clutches are laid each year. The nest is a scrape in the ground, unlined or scantily lined, situated in rough open pasture, a flat wet area or on stony ground. The clutch of 1 – 4 khaki eggs with brownish, black blotches is incubated by both sexes for 30-31 days. The fledging period is 7 – 8 weeks.



Thursday, June 09, 2011

Miromiro, the tomtit



There is a rumour of a tomtit in Greytown. Perhaps a black fantail missing its tail? Difficult to know without a photograph and sightings may be so fleeting that mistakes are made. However, though not likely, it is possible, as there are tomtits close by in the bush in the Waiohine Gorge.

Tomtits are bush birds, not known to frequent towns, but with the storms of late they may have blown into town or just found their way down the Waiohine River. Bellbirds were late in finding a home in our suburbs so it is possible that tomtits could follow their path. There seems to me to be a curious segregation between our endemic birds and the introduced birds we find in our gardens, which by and large shun the bush. Except for the Tui, the bellbird, and Kereru, our endemic birds such as the robin, tomtit, stitchbird, tieke, kakariki, rifleman and Kiwi, shun our presence and stay in the bush. Would that they could find their way into our gardens.

There are five sub-species of Miromiro, the tomtit; North Island tomtit, toitoi, South Island tomtit, macrocephala, Chatham Island tomtit, chathamensis, Snares Island tomtit, dannefaerdi, and Auckland Island tomtit, marrineri.

Our bird, the North Island tomit, the male is a distinctive black and white, with a black head and a white spot above the bill, black upperparts and upper breast, white underparts, and a white wing bar and sides. Its mate is a dull grey and brown and is not so often seen as the male.

The male tomtit has been described as having a cheery little song which he repeats without much variation at frequent intervals, The call notes of both are the more notable, being loud and piercing and repeated rapidly three or four times with widely–opened bill. To hear them suddenly after a long silence in the bush may be quite disturbing. Maori had many superstitions regarding this bird of Maui.

Friday, May 27, 2011

Putangitangi, the paradise shelduck



This being the duck shooting season, paradise ducks in the paddocks around Greytown are especially wary and start sounding the alarm even though I am still a great distance away, walking my dog as I am want to do. The male has the deeper voice, dueting with his mate as they fly off.

Putangitangi, the paradise shelduck, is endemic to New Zealand, that is it is found nowhere else in the world. It was discovered first by Captain Cook at Dusky Sound in 1773 during his second voyage. Cook called it the Painted Duck. They were not a common bird before settlement by Europeans but are now the one endemic bird which has prospered with the conversion of native forest to pasture. They have increased greatly in numbers through this century and are now only partially protected.

They are a large duck and are always seen in pairs except during the moulting season. The drake has a black head with a greenish gloss, the body being dark grey barred with black. The undertail and tertials are orange chestnut. The duck has a white head and the body is a bright orange chestnut.

They mainly graze on grass and weeds, or standing crops of peas or grain which can mean they often get on the wrong side of farmers.

Most paradise duck start breeding when 2 years old and pairs remain together from year to year, returning to the same nesting area. If one bird dies, its mate occupies the same territory and re-mates again. Having adapted to New Zealand when it was largely forested, they are able to nest in trees, in the epiphytes which festoon many New Zealand treees, but now they usually nest on the ground, well hidden beneath a log or clumps of grass. The ducklings have a striking pattern of brown and white down but when they fledge at around eight weeks they resemble adult males, except the females have whiter patches around the eyes and the base of the bill.

Ducks provided Maori with quite a considerable portion of their food supply in some favoured districts, including the Wairarapa. When the ducks were moulting they became very fat and it was at this time that the rahui, which protected the birds during their breeding season, was lifted. The birds having become flightless, could be collected, driven and herded from open lake waters into the water plants lining the shores and there caught in very large numbers. Women and children often took part in the drive, everyone entering the canoes and to make a pleasure jaunt of it. Dogs were also used to capture the birds.

Sir W. Buller tells us that in 1867, 7000 duck were taken in three days at lake Rotomahana. Similar numbers were also being taken at other lakes at the same time. The ducks taken were primarily Parera, the grey duck, but paradise duck were also among the numbers. This was long before Mallard ducks were introduced. When such large numbers of birds were taken many of them were cooked and preserved in their fat in gourds or bark vessels.