Turquoise fire falls from the sky and splashes into the water just ahead of me. Within milliseconds it is airborne again. Only when it alights a moment later is its form made manifest: a pretty little bird with a silver fish in its beak. The dazzling kingfisher has struck again.
Until the 1950s, little was known of the life history of kingfishers, or, indeed, most of our common native birds. Scientific study concentrated on endangered species and seabirds, particularly those of the Southern Ocean, and there was scant information available on such common species such as tui, morepork, kingfisher and native pigeon.
During the 1950s I worked as a veterinarian in a rural practice around Warkworth. Kingfishers were plentiful in the region, and, as they usually nested over summer—conveniently after the bustle of spring calving—I was able to spend much of my off-duty time studying and photographing the shy birds.
The kingfisher family, Alcedinidae (containing some 84 species worldwide), is represented in New Zealand by only two species, the native New Zealand kingfisher Halcyon sancta vagans and the introduced kookaburra Dacelo novaeguineae. Both are classed as forest kingfishers because, unlike many overseas kingfishers, they devour a much wider range of prey than just fish, and differ from the true fishing kingfishers in having stouter, more flattened bills.
The New Zealand kingfisher is distributed widely throughout the country, but is most common in northern sheltered coastal regions. It favours mangrove swamps, tidal estuaries and mudflats, but also inhabits inland rivers and lake shores, and, particularly in summer months, can he found in the depths of forests.
In open country a lone kingfisher may often be seen perching on power lines or other high vantage points searching for prey usually insects, spiders, earthworms or lizards. In coastal regions kingfishers add seafood to their menu—mud crabs, fish, shrimps, etc.
The birds have excellent eyesight, and can spot even very small items of potential food from a considerable distance, then swoop with a gliding dive to capture the prey and immediately return to a perch. Only live prey is taken, and it is always swallowed whole.
I have frequently seen kingfishers take insects, particularly cicadas, from foliage without alighting. Large prey is battered against a branch to kill it and render it more supple for swallowing whole. Indigestible material such as bones, crab pincers and feathers is later regurgitated as pellets.
In winter months, when insects become scarce, many kingfishers move to coastal localities where marine life, especially mud crabs, is available year-round. Tadpoles are a favourite food item for birds living in swamp habitats.
Kingfishers also occasionally capture small birds and mice. I have seen whole mice fed to well-grown chicks, the prey, as always, presented head first and whole. I once observed a mouse’s tail remain protruding from the chick’s beak for over half an hour until digestion of the head allowed the rest of the body to be accommodated.
Photography has proved valuable in recording bird behaviour which is not visible to the naked eye, particularly where movement is rapid or takes place in darkness. Twenty years ago, when high-speed electronic flash units became readily available, I attempted to photograph the native kingfisher diving for fish in a shallow pond. At the time, an American photographer had just had the first photographs of diving kingfishers published in a German camera magazine. He had removed kingfisher chicks from a nest and tallied them. After constructing a small pool in the corner of his studio, he was able to photograph them diving. He commented that it would be impossible to take such pictures in the wild, and it was this comment that provoked me to try.
In an orchard I found kingfishers nesting in a rotting pine tree. Nearby I built a small concrete pond, then made a hide under an avocado tree just two or three metres away. Periodically I put goldfish in the pool. Even from the hide, diving birds were just a flash of blue, a splash and a whirr of wings. I timed the performance with a stopwatch. From the time the bird left its perch a couple of metres above the pool to the time it returned to the perch, with or without a fish, only 1.5 to 1.75 seconds had elapsed.
Recording the dives with a hand-triggered camera proved to be extremely difficult, because the kingfisher’s flight was always faster than my reactions, and the shots seldom had the bird in frame. I eventually found that I had to trigger the shutter immediately the bird left its perch, with the camera prefocused on the point where I anticipated it would strike the water. Most of the time this estimate was well off target, and by the end of the first year all I had were numerous out-of-focus shots for my efforts.
However, many of these images, while of no use for reproduction, showed unusual flight positions which stimulated my interest. The next year I placed a rock in the water, and noticed that the fish tended to congregate around it, so I focused on the rock. After three years and considerable wastage of film I succeeded in getting some worthwhile shots, proving (at least to me) the value of photography in scientific study.
The pictures revealed that fish were not speared, but were gripped crosswise with the bill. They also showed that just as the bird’s bill entered the water a semi-transparent membrane, the nictitating membrane or “third eyelid,” was drawn across the eye to protect it. The membrane could often be seen completely covering the eye as the bird left the water.
During my three seasons of observation of the same pair, the female was the more successful fisher of the two. Adult British kingfishers—a species which has been studied more intensively than ours catch fish on four out of five attempts. Youngsters succeed on fewer than one dive in ten, and at times, in their hunger, will dive repeatedly without allowing time for their feathers to dry. By doing so, they incur the risk of waterlogging their feathers and drowning. Indeed, in this species—which feeds only on fish mortality among young birds is very high.
Successful fishing by diving demands that the bird compensate for refraction of the image of the fish by the water—a problem in anything but a vertical dive. Slow learners of the laws of optics starve.
The New Zealand species, with its wider diet, is less dependent on fish and diving skills, and juvenile mortality is lower.
Kingfishers start courtship and pair bonding in late spring. At this time the male bird is more brightly coloured than the female. Plumage colour changes during the year. After the autumn moult the breast and underwings assume a russet colour, but as the season progresses the feather tips gradually wear down, and the breast becomes paler sometimes almost white during nesting. This phenomenon occurs in several local species (including sparrows, starlings and dotterels) but is probably exacerbated in kingfishers by the adults repeatedly squeezing in and out of the burrow.Pair bonding continues for several weeks, with the male offering food to the female prior to mating.
A likely nest location is selected several weeks before egg laying commences. Favourite locations are vertical cliff faces, clay banks and rotten tree trunks. Occasionally knot holes or small cavities in trees are used as nest chambers. I have also seen nests in clumps of Astelia and in the heads of Phoenix palms.
The typical nest consists of a gently up-sloping tunnel (to exclude water), about four centimetres in diameter and extending for about 25 centimetres before terminating in a circular or oval-shaped chamber 20 centimetres in diameter. Tunnels in rotten trees are often shorter.
Perched a few metres opposite the selected site, the male calls the female with a repeated kek-kek-kek. Once she joins him, they converse with a subdued musical kreee-kreee call which has a rising inflection. The male then flies full tilt to chip a piece from the tree trunk or bank.
The female follows his example, and taking turns they eventually form a depression sufficient to provide a foothold. Working for spells of three to five minutes several times during the day, they continue until they have completed the excavation of tunnel and nest chamber. There is considerable variation in the time taken to get the job done. I have seen a tunnel in a clay bank completed in five or six days, yet it may take more than two weeks to chisel out a nest in a tree trunk.
A clutch of four to six white eggs is laid on the bare floor of the nest chamber among any wood chips or soil crumbs remaining from the excavation. Eggs are laid on successive days, and incubation, which takes from 19 to 21 days, is carried out mainly by the female. The male incubates for short periods while the female is feeding. The male does not appear to take food to the incubating female, as often occurs with other bird species.
The first clutches are sometimes laid towards the end of September, but most laying is in late October and November. Occasionally, clutches are laid in January or February, but these are likely to be second layings due to the failure of earlier broods often as a result of predation by rats or mynas. Although kingfishers are aggressive hunters, I have records of three instances where kingfishers were evicted from their nests by mynas. In two of these cases mynas nested in the plundered burrows.
Kingfisher chicks are naked on hatching, but develop spiky feather sheaths after a few days. Hatchlings are brooded by the female while the male hunts for food, bringing small insects, earthworms, fish or tadpoles. As the chicks grow they are fed larger items, such as cicadas, dragonflies, mud crabs and the occasional lizard or mouse.
To one nest I was watching, which was over a kilometre from the nearest marine habitat, the parents frequently brought mud crabs. The feeding range is usually dictated by the availability of food. In many locations, particularly marine estuaries and harbours where food is abundant, this range may be small.
As the chicks approach fledging, they come to the tunnel entrance to receive food and also to defecate, and the white excreta-soiled entrance, plus the continual rasping sound they emit, is clear evidence of a nest occupied by adolescent chicks. In observations at several nests I have found that the first chick to fledge leaves the nest when 26 days old, the other chicks following at intervals during the next 24 hours.
Before taking their first flight, chicks stick their heads out of the nest entrance and survey the surrounding area. They start this exploration three or four days before fledging. I once spent several hours trying to get footage of the first flight of a chick for the National Film Unit. The bird would put its head out of the nest for a fraction of a second, but by the time I got the camera rolling it had withdrawn it. This cuckoo clock routine repeated itself until my finger was numb. Eventually the bird did make its flight, and I was rewarded with a few precious frames of action.
The first chicks to leave the nest are attended and fed by the male kingfisher, while the female continues to bring food to the younger chicks. Chicks and their parents remain as a family group for at least two weeks after leaving the nest, usually moving to an area where there is an abundant food supply.
Immature kingfishers can be recognised by their shorter bills and the dark-brown mottlings on their breasts. They become fully independent and feed themselves when about three months old.
Though australian kookaburras are much larger than the New Zealand kingfisher, there is a distinct family likeness. There is also a similarity in habit: kookaburras are often seen perched on prominent lookouts, and they also nest in holes.
Kookaburras were introduced to Kawau Island by Sir George Grey in the 1860s. They thrived and extended their range to the adjacent mainland. However, due to limited breeding success, the population remains low. For many years their range extended only from the Wellsford region in the north southwards to the outskirts of the Waitakere Ranges.Recently there have been reported sightings from various parts of New Zealand; one has even come from the Dunedin area.
In Australia, it is said that kookaburras will eat anything that moves. Here there appears to be insufficient large prey available to sustain successful rearing of the chicks. I have seen three instances where well-grown chicks have died in the nest through apparent starvation.
The kookaburra’s maniacal laugh is its most distinctive feature. Cackling out on a quiet summer evening, it can startle the unwary across a kilometre or more. Though, by virtue of its vocal chords, the kookaburra is a much more dramatic attention-grabber, the sleek brilliance of its smaller cousin has won the kingfisher a place in many hearts. What other bird as poet Gerard Manley Hopkins noted can catch fire in its flight?