Sunday, March 4, 2001		Nature

IN pied flycatchers neither of the partners is faithful to the other. As far as the male is concerned, he seems to believe in the theory that if one cannot be certain that he is the father of all the children in the family, he can definitely increase the total number of his children by having at least two wives. The male after mating with one female, leaves her to lay and incubate eggs and he himself rushes off to another territory where he again behaves like a bachelor.

In his new surroundings, he tries to entice every new female he sees and if he succeeds they will mate and she, too, will lay eggs. Now the male leaves his ‘number two’ mate and comes back to the original one.

It has been already mentioned above that neither of the partners is faithful to other. So while the male is away in search of his second mate, his first mate often mates with another male. In this way at the end of the breeding season there may be a number of chicks in the nest but the original male may really be the father of only about three-quarter or half of the young. In other words while the male fathers two families, he is only saddled with the work of rearing one.

Pied flycatcher males arrive in Europe from Africa in spring while females arrive slightly later, by which time the males have established territories in woodlands. An unmated, male on an average, sings 3600 songs a day to lay claim on the territory as well as to entice a mate. From the above fact it seems that females of this species prefer good singers.

This small bird is very hardworking. This quality becomes more evident when it raises its young. It will visit its nest once in two minutes which means over 30 times an hour and makes a total of about 6,000 visits to feed the young.

Another species of the flycatcher — robin-sized kiskadees — is also a very amazing bird, it makes use of both thorns and ants. This yellow-chested bird of Central America is an opportunist that feeds on fish, fruits and small amphibians like frogs as well as insects. They also make use of thorny bull-horn acacia trees to protect their ball-shaped nests. Bull-horn acacias have large, hollow thorns that help protect the nests against grazing animals, but they are also home to aggressive ants of the Pseudomyrmex genus. In return for board and lodging, the ants guard the plants from attacks by insects and birds.

The kiskadees, however, succeed in making use of the acasia’s ant bodyguards. Initially, the ants subject the bird to an onslaught of bites and stings, but gradually they come to tolerate it. However, their anger against the other creatures remains as strong as it was. So the kiskadees are able to incubate from two to five eggs and feed the hatchlings in comparative safety.

Flycatchers belong to the family Muscicapidae which also include fantails and whistlers. There are about 60 genera with about 350 species, most of which are migratory. They are found in Africa, Asia, Australasia and Europe. Most of the members of the family are highly coloured and some of them have crests and wattles. This diverse family has birds with narrow to broad bills with rictal bristles. They have wings which are short and rounded to long and pointed. They make their nests in different places like trees or bush, in tree holes or river banks. They have short legs and their tail is usually short to medium.They usually make cup-shaped nests.