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Hlatikulu Crane Centre The Hlatikulu Crane & Wetland Sanctuary is a rescue, rehabilitation, and captive breeding facility for all three of South Africa’s crane species. There are 15 crane species from around the world and all of them are endangered or under threat to some degree. The main reason for this is that cranes are intimately linked to the grassland biome – often limited to wetlands – and this biome is the most threatened by human activities. We often hear about the destruction of the rainforests but grasslands have been decimated by agricultural activities since our species first developed farming 10 000 years ago. The Blue Crane: The Blue Crane (actually greyish in colour) is South Africa’s national bird. Its scientific name is Anthropoides paradisea, which can be translated as human-like bird of paradise. The Blue Crane is listed as Endangered in the South African Red Data Book. (A Red Data Book lists the relative abundance and conservation status of species. From common to rare to vulnerable to endangered to critically endangered to extinct to extinct in the wild.) The World Conservation Union (IUCN) Red Data book lists the species as Critically Endangered because apart from a very small population in Etosha, the Blue Crane is found only within the political borders of South Africa (ie Endemic to SA). In some parts of its range, namely the eastern part of the country, the Blue Crane has suffered a 90% population drop. This is almost entirely caused by the wholesale modification of grasslands in the high rainfall areas of the country for the growing of food and timber crops, as well as dams, housing estates and tourism developments. Fortunately for the species, the population in the Western Cape is stable. The Western Cape wheat growing region is a winter-rainfall area. Crops are planted around April, allowed to grow through the wet winter and are harvested in early summer – leaving tens of thousands of hectares of short grassland with lots of food – just when Blue Cranes nest. It is quite concerning that the only stable population of this species is found on a human-modified landscape. If too many of the Cape wheat farmers put in a summer crop, or if they change from wheat to rapeseed for example, the species could disappear almost overnight. Blue Cranes pair off at about 4 – 5 years of age and can be found in huge flocks when not breeding. During the breeding season they attempt to establish and defend a territory where they will lay up to 4 well-camouflaged eggs in a rough scrape-nest. Mostly the female will lay 2 – 3 eggs and 1 – 2 chicks will be fledged. Both sexes incubate and both parents help to raise the chicks, normally keeping the chicks separate to prevent fighting. The long feathers are not tail retrices as they appear but are in fact inner wing tertial feathers. They are used extensively for various communication displays. All cranes use elaborate spinning, twirling and jumping “dances” for courtship and territorial displays. The wing feathers of the Blue Crane were sought after by the Zulu kings as part of the royal headdress. At this stage there is no coordinated captive breeding programme for Blue Cranes. However, the skills and capacity exist should this become necessary as Blue Cranes are relatively easy to breed in captivity. Any birds that are injured, poisoned or confiscated by the Authorities are brought here for rehabilitation and release. Birds are released onto the Sanctuary or nearby when there are wild or other released birds in the area. There is a nationwide monitoring programme on Blue Cranes to keep tabs on their numbers. The Wattled Cranes: Walta, a Wattled Crane kept at the Hlatikulu Crane & Wetland Sanctuary, is psychotic. She is under the impression that she is human. In biological terms this is called imprinting and happens when a bird (or other animal) is very young. Wattled Cranes are Critically Endangered in South Africa, with only 236 individuals in the wild. Wattled Cranes are totally dependent on wetlands for breeding purposes and it is estimated that about 80% of the wetlands in their range have been degraded to the point where they are no longer useable habitat. Wattled Cranes in the wild build a large moat around a mound of vegetation. They lay one egg and 2 – 3 days later lay a second. Whereas most birds only start incubating their eggs once the whole clutch has been laid – ensuring that the eggs develop at the same pace – Wattled Cranes start incubating as soon as the 1st egg is laid so that it always develops ahead of the 2nd . As soon as the 1st egg hatches the parents leave the nest and the chick follows, leaving the 2nd egg to die. The Wattled Crane Recovery Programme (WCRP - of which we are a member) monitors the nest sites, and when eggs are laid, they are measure and density tested. About a week later they are tested again & this gives us an approximate hatching date. On the hatching date a fieldworker watches the nest and if the 1st egg has hatched, the 2nd is removed and incubated in Pietermaritzburg before being flown to the Johannesburg Zoo. The chicks are then raised using puppets and costumes to prevent the kind of imprinting that happened to Walta. The WCRP intends to build a captive flock of sufficient size to produce 10 – 12 chicks per year to be released into the wild. A Population Habitat Viability Analysis (PHVA) has suggested that without this intervention the species will be extinct in South Africa within 30 years. The Grey Crowned Crane: There are two distinct subspecies of Grey Crowned Cranes; east African and southern African. The Sanctuary has examples of both. In 1996 we received a telephone call from a group called Stichting Aap in the Netherlands. That organisation normally deals with the rehabilitation of monkeys back into the wild but had ended up with 2 crowned cranes that were being held by somebody there. They asked that if they get the bird to us, could we release them. We happily agreed and Lufthansa (has a crane as a logo) sponsored the flight out to SA. When we collected the birds they were in a bad way from being kept in unfavourable conditions. Both had a chronic bacterial infection of the lower leg called bumblefoot and one of the birds had damaged his crest to the point that it no longer grows. We named them the Bald and the Beautiful. After carrying out some genetic work it was discovered that both birds were of the East African subspecies and had probably been taken out of the wild in Uganda. As these birds are not threatened in that country, and because of the bumblefoot, Baldy & Beautiful are destined for a life in captivity. Shortly after their arrival Baldy & Beautiful, both males, had to be separated because they were fighting. Baldy then developed a pair bond with Nibbler, a South African female. Nibbler was pinioned (cutting the top joint of the wing off to render the bird permanently flightless) and so can never be released. As cranes mate for life we have left them together but we do not allow them to breed because that would be crossing two subspecies and we have no idea what the results of that would be. Crowned Cranes are the least specialised of all the crane species and are the most adaptable. They can be found on farmland and parkland, gardens and golf courses. They nest in summer, in tall vegetation in wetlands or near water, such as the shore of a dam. They usually trample an area of vegetation forming a nest mound and lay up to 4 perfectly white eggs. They are productive birds and will fledge 1 – 3 chicks per year. The main threats to Crowned Cranes are poisoning, powerline collisions and removal from the wild for the pet trade. The conservation actions with respect to crowned cranes are to continue to monitor populations and to release any injured, confiscated or poisoned birds.
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The Blue Crane is South Africa's national bird and is listed as endangered
The Wattled Crane is the largest of the African cranes and the second largest in the world. There are isolated populations elsewhere in African and only 236 individuals in the wild in South Africa
Baldy and Nibbler are of different subspecies but have formed a pair bond. |