Ibisring

Much information has already been discussed on Waldrapp ibis during our ibisday in Paradisio, along with the project to release them in Austria.

 

Latin: Geronticus calvus

French: Ibis du cap 

English: southern bald ibis 

German: Kahlkopfrap 

Spanish: Ibis Calvo 

South-Afrikaans: Wildekalkoen 

Zulu: Umowanele 

References: Hancock en Kushlan, Birds of the world vol.1 & Ibisring

 

This species lives mostly on the higher grasslands of Southern Africa at an altitude of approximately 1200-1850 meters high. It is assumed that there are still 5-8000 birds remaining in this region however there have been some noted local extirpations in some areas. They will nest individually in small groups (+/- 4 nests) or in a true colonial fashion (+/- 40 birds).

 

They find their food by walking through the grass, in which the actual height of the grass seems to play an important role, with knee high grass seemingly being ideal. Once a prey item has been located, they will continue on until they discover something else. Of notable interest is their behaviour of turning over large objects such as stones, wood, leaves, etc to locate their food items.

 

 

They have counted groups of up to 100 birds; it is possible that they congregate at particular feeding locations, arriving from different breeding groups after which they may stay together for a week and then leave for other meadows and grasslands. These movements are likely determined by the availability and abundance of easy prey items, once depleted they will likely leave until insect/prey populations have rebounded at which point they may return; a similar type of behaviour has also been seen in captive individuals.

 

Nests are found on the ground, on cliffs, rock walls etc. Within nests there has been evidence of corvid behaviour in collecting peaces of porcelain, bottle corks, buttons etc. The breeding period is July until October with an average clutch size of 1-3 eggs which are laid every other day. Eggs measure approximately 63mm and weigh about 68 grams.

 

 

There is some discrepancy in terms of the number of chicks produced from pairs; in Transvaal the count is 1.8 chicks per nest, whereas in Nataal this number is only 0.83. It has been found that on occasion pairs may not breed at all and may restart two years later, so that the average fecundity for those years is obviously 0.

 

Young fledge at 55 days, but stay with the parents for another two months. Even after weaning, they are sometimes fed by the adults. There seems to be a preference for a kind of grass now used by some farmers and birds have shown a tendency of moving towards these grazing fields as this has usually been eaten by cattle to the preferred height of the birds. The further education of farmers regarding their hay fields will be important in the continued conservation of this species. Hunting is also of some concern and there are some Zulu’s who use parts of the birds for medicinal purposes.

 

At Pretoria Zoo there is a population kept for release in areas where the birds are no longer found. There was a proposal to bring some of these birds to Europe in the event of a local catastrophe; the good reputation of European breeders will play an important part of determining the success of this program. There is a small captive group of birds in European zoo’s, however not enough to send birds to South Africa, but enough to build a reasonable captive population. Most of these birds are only found in German zoos, however recently it has been possible for private breeders to get some of these birds; some of the founders of Ibisring where quick to jump on this opportunity and there are now birds being held by five members, some only with immature individuals.

 

 

The occurrence of the first private breeding of the Southern bald has been described on the following pages.

 

When the occasion arose that Walsrode suddenly had 5 ibisses available, I jumped to the opportunity and bought them. They turned out to be 2 males, 3 females, two of them where two years old and three of them were young from that year.

 

They were kept in a typical ibis aviary, about 3m high and 8m x 12m in size; a regular net was used on the top of the aviary. There was an inside shelter of 4m x 8m where in the winter a small fuel heater kept it frost free. Sharing the aviary were some spectacled, spoonbills and storks.

 

Diet is composed of mainly soaked Lundi regular, with the occasional fish and day old chick.

 

For nesting there are two elevated baskets; one and two meters high respectively.

 

After a while a pair formed in the group, the others remained as a trio. At this point the birds where 2/3 years old. Early in April the couple started to gather old leaves and dry grass into a basket, the first nest was now under construction. By the end of April the first egg was laid, then two more, with a day in between each.

 

The eggs were left with the pair so they could gain experience rearing their own chicks. Both male and female shared in incubation duties, but when an egg disappeared I decided to pull the remaining two and put them in the incubator. The eggs had not lost sufficient weight so this was attempted to be corrected, however both chicks died before hatching.

 

Meanwhile, the couple already had started a second clutch, this time the eggs were put into the incubator from day one. The incubation parameters were 101°F and humidity +/- 45%.

 

Every two days the eggs were weighed and were compared to the measurements compiled by Ibisring (see here). After 23 days the first chick was born with the other two soon following.

 

The young were hand reared using Lundi regular, fish and day old chicks all mixed into a porridge. At feeding time this was warmed to 35°C and given through a syringe every two hours for the first few days and then every four and six hours as the chicks grew.

 

At the age of 10 days they started becoming more mobile and I placed them in a larger cage under a heat lamp where they find a temperature to their liking. From that point onwards their food was gradually changed to a diet of fish, wet Lundi regular, pieces of chick leg, etc.

 

Of note is that once these birds begin to recognize their keeper as a source of food, they begin to behave rather aggressively towards one another and will bully smaller siblings. If they are left to their own devices they settle down, but resume their aggressive response when they know food is coming. This behaviour continues until they reach weaning age and begin feeding themselves.

 

Closed bands were placed on the birds at +/- two weeks of age.

 

Once feathers were developed, they were moved to a larger aviary with an inside shelter, which requires the keeper to herd them inside during poor weather conditions otherwise they are at risk of exposure.

 

The trio that was being held in the adult aviary eventually formed a pair and began laying eggs. The remaining unpaired birds were paired up with offspring produced and then the others were dispersed to other breeders.

 

 

The Southern bald is one of my favourite species and belongs in all collections; their brilliant feathering, red head and interesting behaviour warrants them a favoured spot in the aviculturists heart. They will take to sun bathing during periods of warm weather where they may sit for hours on end with their wings wide open to catch the sunlight.

 

Papers needed for these birds: Cites A in Europe, rings 14 mm, certificate of birth to cites bureau and application for documents.

 

I hope that with this article, I have helped piqued some interest of the membership towards this unique species and encourage them to attempt working with them so we can build a strong captive population and maintain them in responsible manner as Ibisring advocates for other species.