The Formosan Blue Magpie

Rearing children is the natural duty of all parents, and birds are no exception. It is rare, however, to find adult birds apart from the parents assisting in rearing young birds. The Formosan blue magpie is the only species of bird in Taiwan where other adult birds share in the task of feeding the fledglings, dubbed by ornithologists the "nest-side helper system."

Blue magpies have a strong social sense, often appearing in groups. Many birds that normally flock together seek out partners at breeding time and take them away to get on with rearing the next generation on their own. But blue magpie flocks stay together all year round. Come breeding time, the mother bird still incubates her eggs and keeps her fledglings warm, but the feeding is not left entirely to the male bird. He is helped by other adults who take it in turns to feed the young and bring food for the mother.

It has been established that the helper system among birds normally has advantages for the parent birds in bringing up their young; but so far researchers have not been able to define precisely what advantages are derived by the blue magpie.

This is simply due to lack of research on the blue magpie. Unique to Taiwan, this species has only been under observation by Academia Sinica's Institute of Zoology for one year.

Taiwan, a continental island, was attached to the mainland in ancient geological times and its fauna and flora mostly migrated from east of the Himalayas. Later, as earth's climate changed, the polar ice-caps melted and sea levels rose, forming the Taiwan Strait. Taiwan's animal species were then cut off from the mainland by the sea.

Although the Taiwan Strait is only 130 kilometers wide at its narrowest point, birds which were poor flyers and non-migratory just had to do their best to adapt to the island's topography, climate, vegetation and natural predators. . . . eventually evolving into unique species or subspecies. The Formosan blue magpie is one of the 14 bird species unique to Taiwan.

Blue magpies live in broad-leaved forest or wooded areas at between 200 and 1,000 meters above sea level. They belong to the raven family, part of the Pica race. Being of the same family as the crow, you might not think they could be attractive. But apart from its black head and breast and its red bill and legs, the blue magpie's body is bright blue all over. Its coloration changes with the light and its surroundings, gleaming like blue glaze under the sun.

Birds of the Pica race have long tail feathers, a feature inherited by the blue magpie too. It has four white-tipped tail feathers, of which the middle two can grow as long as 40 cm, accounting for 70 percent of the total body length. This is why bird-lovers call it the "long-tailed mountain maiden."

Too long a tail is burdensome in flight, and the blue magpie doesn't fly long distances, preferring straight hops. Their flocks keep a strict order, neatly following their leader one by one in flight.

Despite their striking appearance for members of the raven family, blue magpies have retained the raven's noisy nature. In its vicinity you can always hear loud cawing.

One-time assistant researcher at Academia Sinica's Institute of Zoology Feng Feng-k'uan, who has observed the blue magpie, points out what an aggressive bird it is. Climbing trees to ring young birds in the nest, he would often be attacked by adult birds in waves like dive-bombers and always had to wear a crash helmet.

Blue magpies love juicy fruit, especially papaya. Farmers in the mountains often discover their papayas have been eaten hollow, although only a round hole is visible from the outside. Hunters often use papaya as bait to lure blue magpies into their traps.

They also eat insects, lizards, snakes and small mammals, even attacking the young and eggs of other birds. Academia Sinica's research report mentions that smaller birds in the vicinity such as Chinese bulbuls, cinnamon sparrows and little drongos will often attack blue magpies fiercely as they fly past, sometimes forcing them to change course. Institute of Zoology researcher Liu Hsiao-ju thinks they evidently know the blue magpie is a natural predator and so ward it off.

Blue magpies breed in March and April, laying four to six eggs per nest. If left undisturbed they will return to the same area each year to build their nest, even to the very same tree.

When an adult returns to the nest with food the fledglings ask to be fed by fluttering their wings. Fluttering is an important action for blue magpies; even fledglings know how to do it, and adult birds do it as a sign of friendship.

An omnivorous bird, the blue magpie mostly feeds its young on animals, perhaps through an instinct to give its offspring the best food it can. If an adult catches a hairy caterpillar it will strike it against the tree to remove the bristles before feeding it to its nestlings.

Nestlings have a short intestine, which means that eating quickly stimulates them to defecate. To keep the nest clean the adult catches the dropping as soon as the nestling raises its behind. The oval dropping is enclosed in a membranous sac which makes it easier for the adult to dispose of it well away from the nest and avoid revealing its location to predators. The fledglings are "attended to" by adults in this way throughout the four or five weeks from hatching to learning to fly.

Blue magpies are regarded as highly capable of adapting to and exploiting their environment. Researchers have observed adult blue magpies inspecting street lights and porch lights at daybreak and carefully searching out any hidden or dead insects near them. They will even take moths from the moth-collection gauzes set up near the Taiwan Forestry Research Institute's Chienping work station.

They also like building nests in bamboo groves or orchards near human habitation. According to Wild Birds, published by the Audubon Society of America, as long as local people leave them undisturbed many birds will migrate from their natural habitat to human surroundings because these tend to harbor fewer natural predators.

Scientists have wondered about this behavior of animal species utilizing human surroundings: At a time when mankind is causing large-scale environmental change, the only species that can survive may be those flexible enough to accept human activity. In the evolutionary process, has man already begun playing the role of "bringing about the extinction of species unable to adapt to mankind, and making those that can adapt change with mankind"?

In Save the Birds--Mankind's Future in Avian Species Survival it is stated that the Formosan blue magpie faces a grave threat from bird-catchers due to its settled nesting habits and pretty appearance. Of 16 blue magpie nests observed by Academia Sinica only three were untouched by man, while the fledglings were stolen from 70 percent of the rest. Its low rate of reproduction now threatens to place the Formosan blue magpie alongside the yellow tit, the emperor pheasant and the Swinhoe's pheasant as one of the island's rarer unique bird species.

Will the blue magpie be a species that "adapts to man and changes along with him," or one that "cannot adapt to man and becomes extinct"? As yet we do not know the answer.

[Picture Caption]

Blue magpies flutter their wings as fledglings to ask for food and as adults as a sign of friendship.

In addition to the parent birds, other adult blue magpies of the same flock also assist in feeding the young.

Blue magpie nests are generally built in the topmost branches of broad-leaved trees.

In addition to the parent birds, other adult blue magpies of the same flock also assist in feeding the young.

Blue magpie nests are generally built in the topmost branches of broad-leaved trees.