Breeding the Indian Verditer Flycatcher Muscicapa thalassina

Abstract

There are three flycatchers commonly known as verditer flycatchers: the Philippine, Nilgiri and of course the most familiar of all, the Indian Yerditer Flycatcher. A denizen of lightly wooded, fairly open country, the Indian Verditer is a lively and attractive bird earning its living by hawking insects from its usual perch of a bare twig.

Measuring only about 15 cm (6 in.) the two races of the Indian Yerditer M. t. tbalassina and M. t. tbalassoides occupy a large range, stretching from the Himalayas to Indochina, Thailand and Malaysia as well as Sumatra and Borneo. The entire plumage of the male bird is a bright green-blue, with an even brighter color on the head and throat although the wings and tail are somewhat darker. The !oral area is made prominent by a small black patch and the under-tail coverts are highlighted by a dirty white fringe. The female resembles the male but is duller in color throughout and small white spots pepper the throat and sides of the chin.

Once acclimatised the Verditer will prove reasonably hardy, but will certainly need heated winter accommodation if kept in an outside flight. The diet is fairly straight forward: I prefer a fine grade insectile mix to which I add various live foods such as meal worms, wax moth larvae, small crickets, blow flies and chrysalises. Approximately 15% of the total diet is made up of live food.

Here at Sedgwick County Zoo, our pair ofYerditers are housed in an aviary measuring 3 m x 1 m x 2 m high (10 ft. x 3 ft. x 6 ft. high). It is not an outdoor flight but just one of a complex of aviaries contained within a purposely built "off exhibit" facility. The building' temperature is thermostatically controlled and the air humidified by means

of a mister system programmed to come on three times a week for a duration of five minutes. During the summer the afternoon temperature of the building will rise to about 28°C (82° F) and the humidity level will be about 65 percent. During the winter the building will get no cooler than about 16°C (60° F).

In August 1993, our pair of flycatchers successfully fledged one youngster. Their aviary was not heavily planted but merely decorated with two hanging baskets and a 1 m (3 ft.) high ficus tree. This particular pair has been in captivity for several years and has therefore become quite steady in the company of people. A more nervous or newly imported pair would certainly benefit from a thickly planted aviary, especially since in the wild the verditer flycatcher retreats to denser forests to breed.

Nest building began on June 22, and lasted for 13 days. A substantial nest was built within an empty half openfronted box measuring 15 cm x 15 cm x 23 cm high (6 in. x 6 in. 9 in.). The nest itself was a full 7 cm (3 in.) deep

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grasses. However, the major ingredient by far was wool. Bison (Bison bison) wool found scattered throughout the zoo's North American Prairie exhibit was used by the flycatchers to build almost 60% of their nest. Interestingly, the birds did appear to discriminate between nesting materials that reflected different levels of brightness. 111e whiter colored wools and plant fibers were repeatedly ignored in favor of the duller shades such as brown and green. Presumably brighter materials are considered too conspicuous to risk the safety of the nest.

Throughout the nest building proces and indeed the entire nesting period, the female was extremely adept at concealing her work. Only once did I catch her red-handed and in the process of carrying (bison) wool to the nesting box. But even then when she saw me and realizing she could do nothing to disguise her activity, she froze, looking as guilty as it's possible for a bird to look while trying to remain nonchalant. Not once did I actually see her take nesting material to the box, hut her absence made her very conspicuous and it was therefore easy to surmise her labors. While she worked busily the male appeared to play no part in the nest building, although he would stand guard and alert her to the approach of danger. At such times the very rapid. loud rattle of a song was uttered. Quite a pleasant sound, this appears to be the only voice the verditer flycatcher has; I have never been able to detect any kind of a call-note.

A clutch can consist of anything from three to five eggs and sometimes a pair may even only produce two. This pair laid three eggs, almost immediately after the nest was complete.

Measuring about 14mm x 20mm C.56 in. x .80 in.), the eggs were devoid of markings being simply a plain, soft ivory color.

Incubation began with the laying of the first egg, and the first chick hatched 14 days later. The second chick hatched just over a day after that with the third egg failing to hatch; unfortunately, it was infertile. Sadly within the first day of its life the smaller of the chicks died, but the larger of the two thrived and it fledged only 17 days after hatching.

As rearing food, a variety of small live food was provided; the favorite food were flies of "mini" maggots. The maggots themselves, which are only about 6mm (.24 in.) long, were also popular but were only considered by the birds when all of the flies had been eaten. A satisfactory way of dispensing the flies is to offer them in a jar whose lid is perforated with a few holes. The flies then escape in small groups, slowly enough to allow the birds to catch them. One must take great care, however, that sufficient flies escape to nourish the youngsters. To guarantee an ample supply it is preferable to deliver handfuls of them to the aviary periodically, in addition to those continually emerging from the jar. Small meal worms were also provided as well as the usual insectivorous diet. All live food was generously sprinkled with calcium lactate and vionate powders.

A slightly smaller edition of the adult birds, the youngster's plumage hinted at the green-blue of the future but for the present displayed mostly a dull gray-brown. It was a healthy bird and reached independence about three weeks after fledging.