Breeding the Chestnut-capped Ground Thrush at the Lowry Park Zoological Garden

Abstract

On January 8, 1988, a pair of Chestnut-capped Ground Thrush, Zoothera interpres, was purchased by the Lowry Park Zoo from a private bird importer in Tampa, Florida. The birds were wild-caught in Malaysia and were of unknown age when received by our zoo.

Natural History Notes

The Chestnut-capped Ground Thrush, a bird of about six inches in length and of distinctive coloration, is found throughout Malaysia and is a resident in the Bornean lowlands. This bird is quite rare and field notes indicate that it is shy and retiring (Smythies, 1960).

Captive Facilities

Laporoscopy determined our pair to be a male and a female. The pair, after passing through the zoo's one month quarantine, were housed in a wood framed entrance aviary in front of the zoo's one-half acre free flight aviary. This flight also housed 1. 1 Gouldian Finch, Chloebia gouldiae, 1.1 Roul Roul, Rollulus roulroul; 1.1 Leclancher's Bunting, Passerina leclancherii; 1.0 Red-legged Honeycreeper, Cyanerpes cyaneus, and 1.1 Blue-tongued Skink, Tiiigua scincoides, 0.0.4 Radiated Tortoise, Geochelone radiata. Two sides and the top of this 3' wide by 10' long by 8' high outdoor flight are of 1/2" PVC coated hardware cloth with plexiglas viewing panels. The ends of the aviary are stud wall construction with T 1-11 plywood interior cladding. Composition of floor is dirt with plantings of ficus, bamboo, bromeliads and liriope. One infrared strip heater ( 4' long) is fixed in a corner of the aviary and turned on when outside temperatures drop below about 45°F.

Courtship, Breeding and Incubation

The birds were together 21 months before laying the blotched reddish brown on pale grey egg that would become their first viable chick. (Please see the clutch chart for egg data.) The birds engaged in frequent mutual vocalizations (singing) and associated head moving behaviors but no other obvious courtship displays were noted. Four clutches were laid with 2, 2, 3 and 3 eggs, respectively noted. Nesting occurred from May through September. All eggs in all clutches were fertile, and both parents incubated the eggs. A 1/2" welded-wire cup placed in the crotch of a 6' ficus tree, about three feet above grade, was chosen as the nest site and was filled with primarily long-leafed pine needles. Two nest sites were made available for this species. Perches were of natural wood, dried grape vines and the tree species previously mentioned. After three unsuccessful attempts at parentrearing this species, the fourth clutch of three eggs was pulled on October 1, 1989 for artificial incubation. All eggs hatched, with two young expiring at two days, the third and last chick, however, successfully being hand-raised and surviving to this day (now a surgically-sexed male).

Diet

A commercial diet of Zeigler Softbill and Ziegler Bird of Paradise was fed the parent birds along with greens, fruit, nectar, crickets and mealworms. At least four different attendants serviced this exhibit and 500,000 to 700,000 people per year passed within three feet of the nesting site. Water was available in a fourinch deep cement pond with a surface area of about two square feet.

The hand-rearing diet, consisting of finely chopped pink mice soaked in Emeraid vitamin solution, was fed with forceps for the first four days, initially at two hour intervals. On the fourth day, chopped pinks dipped in Gerber's Garden Green Vegetables (baby food) were fed. By day ten, soft fruits were added and the mixture was 50 pecent fruit/vegetable and 50 percent animal protein. The frequency of feeding was gradually reduced and amount per feeding increased appropriate with the chick's growth.