Three Rare African Finches Bred at Riverbanks Zoo

Abstract

In June, 1980, Riverbanks Park acquired three species of African Estrildine finches, 3.3* black-bellied firefinch (Lagonosticta rara), 3.3 crimson seedcracker (Pyrenestes sanguineus), and 4.3 blue-bill (Spermophaga haematina). The ranges of these three species overlap somewhat throughout west and central Africa where they share a similar bushy, grassland habitat. Though common in the wild, they have apparently eluded frequent capture because they are unusual in private or zoological collections at this time. The birds obtained by Riverbanks all adapted to captivity quite well, and exhibited nesting behavior with varying degrees of success within their first year and a half at the zoo.

The birds were all housed together initially in a glass fronted exhibit measuring 3mf high, )m wide and 2.)m deep, with no natural light. Duro-test grow lights and incandescent lights were on a fixed 12-hour schedule throughout the year. The exhibit was designed with an artificial tree and ground cover consisting of various dried grasses, bushes and liriope (ornamental grass). The diet was a standard finch seed mix, supplemented with an insectivore mix (1), egg food (2), greens, and mealworms, all offered daily, regardless of nesting activity.

Very little interaction occurred between the species but intraspecific pairing and territorial disputes began almost immediately. Gradually a pair of each new species was left in this exhibit and other pairs were moved to new locations.

The bluebills were the first to actively show signs of pair bonding. These attractive little birds are named for the male's pearl-blue bill. He is primarily glossy black with a bright red breast. The female is no less striking, being a duller red but having a distinctive black and white spotted belly. A pair bond had

• Indicates 3 males (left of period), 3 females (right of period).

t 1 meter = 39.37 inches

clearly formed between two birds who started carrying nesting material, primarily dried grasses, to various places in the exhibit for several months. In February, they began concentrating efforts on a standard finch box attached to the wall about 6 feet from the floor. The addition of short strips of burlap in early March seemed to accelerate the nest building because shortly after that, one bird was always in the box, presumably incubating eggs. This was confirmed on March 13th when at least 5 eggs could be seen in the tightly woven nest. Small mealworms and larger white mealworms which had shed their outer skin were added to the diet in anticipation of the hatch date but the parents were very secretive in their feeding habits. The nest was checked again March 19th and at least two babies could be seen. There was concern over the parents' inattention to

the nest so it was checked again three days later. This time 5 yellow mouths with distinct black spots could be counted. It was also noted that the chicks had distinct yellow papilla on the edges of the beak, characteristic of many finches. Mealworm and egg food consumption increased over the next few weeks and the adults were also observed feeding on the local roach population.

On April 5th the first two chicks fledged, 18 days after hatching. Three more were out over the next two days. No interaction was observed between the fledglings and the two other species still in the exhibit. The young birds were removed 11 days later, which may have been too hasty, as one died two days after that and a second died ten days later. No specific cause of death was ever determined.

The parents immediately renesred but went through three attempts before successfully raising four more young. This time the fledglings were left in the exhibit until they were six weeks old, at which time they had begun to obtain their adult plumage and their sex could be determined. Once again the adults immediately went back to nest but failed in three attempts. At this point they were moved to a new exhibit and one of the pairs which had been removed in the early pair bonding was returned.

The original pair continued to nest in a new exhibit but repeatedly failed to rear young. In early March of 1982, two eggs were removed at the time of laying and placed under society finches. The societies began incubating immediately despite a slight size difference in the eggs and proved to be model parents when two chicks hatched at 14 days. The societies were fed the same diet as the blue-bills, with the addition of some newly acquired mini-worms (Tribolium confusum), but seemed to prefer the small mealworms. Successful rearing has been repeated with another pair of societies since then.

Another blue-bill pair followed a similar pattern of behavior in an exhibit 3m high by 2m wide by 2.5m deep, where they were housed by themselves. They nested on the ground two months after being removed from the original group, hatched four chicks after a 14 day incubation period and fledged all four at twenty days. Their daily mealworm consumption peaked at about 150 mealworms approximately ten days after hatching.

The parents then appeared to be following the same pattern of going back to nest too quickly so they were removed to a holding area to delay breeding. Two

months later they were put in a wire cage, lm high, lm wide and .5m deep and given nesting material and a finch nest box. Within a month they chose to build a nest on the floor, weaving a tight little hut with a side entrance, much as they had in the exhibit. This time two chicks were raised. Another attempt at nesting produced only infertile eggs. The adults were moved again into an even smaller box cage measuring . 7m high, lm wide and . 7m deep and given a nest box and grasses. One more attempt failed before March, 1982 when one chick was reared in the box.

Interestingly, the third pair of the group never exhibited nesting behavior even though given all the same opportunities. In January, 1982, the female of this pair was replaced by a seven month old offspring female and the change was immediate. The pair began nest building and laid eggs in February. Two babies lived to ten days before mysteriously disappearing. When the birds nested again, the two chicks vanished at 18 days of age and vermin were suspected so all the birds were removed and the exhibit was rebuilt.

The crimson seedcrackers are probably the most striking of the three species obtained. Slightly larger than the blue-bill, the male is a vibrant crimson in color over much of his body, offset by a deep brown on the wings, back and belly. The eyelids are white and are made even more conspicuous during breeding displays. The female is similar but duller over all.

One male died in the first month from a septicemia caused by an eye injury, leaving two males and three females to be placed on exhibit. Pair bonding was not as obvious as with the blue-bills, but some pairing off was observed, so, in an attempt to encourage this, two birds were removed, leaving one male and two females. When it became possible to determine the male's preference, the extra female was removed. Shortly thereafter, nest building began in earnest. Both the male and female worked daily carrying dried and fresh grasses, shredded palm leaves, burlap strips and Spanish moss to various locations before concentrating on some upper branches. They worked at this site for six weeks, building a loosely domed structure with some semblance of a side entrance hole. It collapsed before being used and the remains were removed to encourage a fresh start which began the next month. They worked on this for another month with no significant progress.