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hand-rearing Hand-rearing hemipodes at the New York Zoological Park JOSEPH BELL & DONALD BRUNING New York Zoological Society, Bronx, New York 10466, USA The bird world contains many fascinating cases of species very similar in appearance whose taxonomic relationships are really quite distant. The hemipodes are a case in point. Whde these small, three-toed, grounddwelling birds rescmblc true quails, they are actually more closely related to the cranes, rails and bustacds and have been placed in the order Gruiformes, suborder Tumices. Found only in the Old World, from southern Spain and Portugal on the west to the warmer regions of Asia on the east, there are 14 species of hemipode ranging to southern Africa and Australia with representative forms on many of the islands and archipelagos of the area, including the Philippines, New Guinea and Madagascar. The four-toed Collared hemipode or Plains wanderer Pedinnornirs torquutus, found only in Australia, is usually treated as a separate, mono- typic family (Pedionomidae). Hemipodes exhibit an interesting social bebaviour pattern, namely the reversal of the parental role during courtship and nesting. Allied with this behaviour, found in less than 5% of all bird species, the 99 are larger and more colourful than the 88. Females fight over and defend their mates and nesting territories in much the same way as do the 88 of most other bird species. After a d has scraped out a nest site under a clump of grass or a small bush, the 9 deposits eggs and her role is then complete. She moves off to seek the company of another 8, or group of 88, and it is up to h a former partner to incubate the eggs and rear any chicks that hatch - a unique arrange- ment that might well please some present-day human social reformers. Henlipodeswere first added to the Bronx Zoo's collection in 1926. During the next 21 years, several of the 13 species of typical buttonquail, Tlimix, were exhibited, but there is no record of successful breeding. In October 1970 a group of Kurrichane hemipodes Turnixt sylvatica lepirrana, an African form, was acquired for display in the World of Birds, a new building under construc- tion at the time. Early in the following year six of these (two and four 88) were established in a scrubland sceiie measuring rougllly 9 x 3 x 5 m high, fully skylighted and planted with bcaii- carnia, euphorbia, yucca, sanscviera and crassula. Among the other birds in this display werc quailfinches Ortygospiza, sniall wliydahs Vidi40, waxbills Uracginthus and several species of sun- bird Nectariniidae. By the end of March the hemipodes had started laying. The first ten eggs were broken by the adults within a week and it was decided to try artificial incubation. Of the ten eggs collected by the end of April, five wcrc sct in each of two Humidaire model SO, forced-air incubators. One machine was regulated to maintain a tciiiperature of 36-4"~, with 67% relative humidity, while the other called for a 37.5"~ and 82% humidity. Of tlie five eggs set in the first machine, four were fertile and three were hatched and reared. Two of the eggs set in the second machine appeared fertile and one hatched, but the chick survived only a few hours. From then on, all eggs artificially hatched were incubated at 36.4"~ and 67%, relative humidity. Breakage continued to bc a major deterrent to success. Eventually increased hostility between the two ?? forced the removal of one pair and while this innovation solved the problem offigliting, it had no effect on the break- age rate. In addition, the number of eggs laid by the single 9 with four consorts was considcrably less than the number laid by each of four subse- quent ?? housed with six 88. During 1972 a total of 67 cggs was laid. Over 30 were broken, 18 were fertile and 16 hatched. All of the eggs were laid between Novcmber and June, with the largest numbers being produced iii February, March and April. Thc current breeding season (1973) may be a record one; so far 60 eggs have been recorded for the January-February

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Page 1: Hand-rearing hemipodes at the New York Zoological Park

hand-rearing Hand-rearing hemipodes at the New York Zoological Park JOSEPH BELL & DONALD BRUNING New York Zoological Society, Bronx, New York 10466, USA

The bird world contains many fascinating cases of species very similar in appearance whose taxonomic relationships are really quite distant. The hemipodes are a case in point. Whde these small, three-toed, grounddwelling birds rescmblc true quails, they are actually more closely related to the cranes, rails and bustacds and have been placed in the order Gruiformes, suborder Tumices.

Found only in the Old World, from southern Spain and Portugal on the west to the warmer regions of Asia on the east, there are 14 species of hemipode ranging to southern Africa and Australia with representative forms on many of the islands and archipelagos of the area, including the Philippines, New Guinea and Madagascar. The four-toed Collared hemipode or Plains wanderer Pedinnornirs torquutus, found only in Australia, is usually treated as a separate, mono- typic family (Pedionomidae).

Hemipodes exhibit an interesting social bebaviour pattern, namely the reversal of the parental role during courtship and nesting. Allied with this behaviour, found in less than 5% of all bird species, the 99 are larger and more colourful than the 88. Females fight over and defend their mates and nesting territories in much the same way as do the 88 of most other bird species. After a d has scraped out a nest site under a clump of grass or a small bush, the 9 deposits eggs and her role is then complete. She moves off to seek the company of another 8, or group of 88, and it is up to h a former partner to incubate the eggs and rear any chicks that hatch - a unique arrange- ment that might well please some present-day human social reformers.

Henlipodes were first added to the Bronx Zoo's collection in 1926. During the next 21 years, several of the 13 species of typical buttonquail, Tlimix, were exhibited, but there is no record of successful breeding. In October 1970 a group of Kurrichane hemipodes Turnixt sylvatica lepirrana,

an African form, was acquired for display in the World of Birds, a new building under construc- tion at the time. Early in the following year six of these (two and four 88) were established in a scrubland sceiie measuring rougllly 9 x 3 x 5 m high, fully skylighted and planted with bcaii- carnia, euphorbia, yucca, sanscviera and crassula. Among the other birds in this display werc quailfinches Ortygospiza, sniall wliydahs Vidi40, waxbills Uracginthus and several species of sun- bird Nectariniidae. By the end of March the hemipodes had started laying.

The first ten eggs were broken by the adults within a week and it was decided to try artificial incubation. Of the ten eggs collected by the end of April, five wcrc sct in each of two Humidaire model SO, forced-air incubators. One machine was regulated to maintain a tciiiperature of 36-4"~, with 67% relative humidity, while the other called for a 37.5"~ and 82% humidity. Of tlie five eggs set in the first machine, four were fertile and three were hatched and reared. Two of the eggs set in the second machine appeared fertile and one hatched, but the chick survived only a few hours. From then on, all eggs artificially hatched were incubated at 36.4"~ and 67%, relative humidity. Breakage continued to bc a major deterrent to success. Eventually increased hostility between the two ?? forced the removal of one pair and while this innovation solved the problem offigliting, it had no effect on the break- age rate. In addition, the number of eggs laid by the single 9 with four consorts was considcrably less than the number laid by each of four subse- quent ?? housed with six 88.

During 1972 a total of 67 cggs was laid. Over 30 were broken, 18 were fertile and 16 hatched. All of the eggs were laid between Novcmber and June, with the largest numbers being produced iii February, March and April. Thc current breeding season (1973) may be a record one; so far 60 eggs have been recorded for the January-February

Page 2: Hand-rearing hemipodes at the New York Zoological Park

HAND-REARING

20.

10.

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period and 24 chicks hatched from 30 fertile eggs.

E G G S AND CHICKS

Hcmipode eggs laid during 1972 averaged 4.25 g in weight. Incubation periods (in an incubator) varied from 14 to 15 days with more than 80% hatching on the fourteenth. While chicks average less than 3 g at hatching, they grow rapidly after the first two or three days, with an average weight gain of about I g per day in the first month. At the end of the second month, normal chicks approach the 50-70 g weight range of adults. Female sexual maturity is attained in less than three months; a group of five birds hatched here on 4,s and 6 January 1973 produced three eggs on 25 March.

HAND-REARING

Once a chick has 'pipped' or starred its eggshell, the egg is placed in a Lyons forced-air hatcher (model A-475). Glass panels on both the front and top allow observation without disturbing the hatching process. Newly hatched chicks are kept in the hatcher for a 'drymg-off' period of up to 12 hours and then moved into small (20 x 25 x zs cm high) brood boxes. These brooders are heated by a light bulb with a reflector that covers about half of the upper surface of the box. The remaining half has a sliding lid which can be left

in any position, from open to fully closed, to help regulate the temperature within the box. The size of the light bulb is also an aid in modify- ing the internal temperature of the brooder. By using a 100 watt light bulb, a temperature gradient of 33.3 to 40"c can be maintained in a brooder of the dimensions quoted. At these high temperatures chicks are quite active and this activity appears to be the key to inducing them to feed. At cooler temperatures they are lethargic, often huddling in a corner and showing little interest in any of the food items offered.

Active chicks will peck greedily at very small mealworms Tenebrio held in a pair of forceps. If live food is offered at least eight or ten times a day most chicks start eating before they are two days old. At first they have difficulty in swallow- ing even the smallest mealworm but they soon learn to manipulate them and by the end of the first week they are capable of taking worms of a half and two-thirds the full size. At three or four days of age they begin to pick up and eat small mealworms dropped in front of them. They will also pick and eat small crumbs of Gaines Meal and Turkey Crumbles sprinkled over their backs. These items are also taken from small food dishes or strips of paper placed on the wire floor of the brooder; adding a few tiny mealworms helps to attract the chicks to the dry food. It is wise,

WEIGHT (g)

30 ..I AGE (days)

Fig. I. Average growth rate of 25 hemipode Turnix sylvntica lepurana chicks hatched and hand-reared at the New York Zoological Park in 1973. On Day 75 the average weight for a group of eight 99 was 62 g, and for IZ$$, 51 g.

0

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HA N 1) - R E A R I N G

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30-

20-

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however, to continue occasional hand feeding for several days after the chicks have been observed taking food themselves.

Daily weighings (Figs I and z ) and observation of activity levels are the best index of progress. If the chicks do not continue to gain weight rapidly, hand-feeding must be increased or, if necessary, reinstituted. In most cases little hand- feeding is required after the second week. Because of the high temperature in the brooder, it is part- ticularly important that water is accessible at all times to avoid dehydration. Small, shallow dishes and jar lids are ideal. Small stones added to each container allow a tiny chick to drink without getting into water of any depth and becoming soaked.

From both educational and exhibition stand- points it would be far more desirable to show the complete reproductive activities of heniipodes, from courtship and nesting to the successful rearing of chicks in the normal parental fashion.

Limited space and the demands of a mixed collection make a display of this kind impossible. As an alternative, a special exhibit in the World of Birds features glass-fronted incubators and brooders where the visitor can view young hemipodes (and other species) being hand-reared, with graphic information on their species characteristics, habits and status in the wild.

PRODUCTS M B N T I O N B D IN T H B TEXT Gaines Dog Meal: a dry dog food manufactured by General Foods Corp., 250 North Street, White Plains, New York, USA. Humidaire (model 50) Incubator: mmufacturcd by Humidair Incubator Company, Wayne Street, New Madison, Ohio, USA. Lyons model A-475 Glass Incubator: manufactured by Lyons Rmal Electric Company, 207s Moore Strcet, San Diego, California, USA. Turkey Crumbles: a commercial poultry chick starter manufactured by Ralston Purim Co., goo Checkerboard Square, St Louis, Miss. 63199, USA.

Manuscript submitted 24 April 1973