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The
Blue Crane of South and Southern Africa The Blue Crane - Anthropoides paradisea The claim to fame of the Blue Crane is that it is South Africa's national bird (have you checked your 5-cent piece lately?) - not only is it almost endemic to South Africa (except for a tiny population of 50-80 in Namibia) but so too is it the only crane in the world with no red on it anywhere. Instead, to ward off predators, the elegant Blue Crane puffs up its smooth grey-blue head like a cobra, and hisses, dancing aggressively towards its predators. Within South Africa, there are three strongholds for the Blue Crane: the grasslands of KwaZulu-Natal, North-eastern Free State and South-eastern Mpumulanga; the central Karoo region in North and Eastern Cape, and the wheat-producing regions of the Western Cape. Despite being a grassland bird, these cranes also occur frequently on cultivated agricultural lands and pastures, and use wetlands for roosting and sometimes for breeding. The Blue Crane has left the former Transkei region and during the past 20 years, numbers have declined by as much as 90% - from more than 100 000 during the 1980s, to between 20 000 and 25 000 individuals today. Biological needs Unlike the stately Wattled Crane, the elegant Blue Crane is the least wetland-dependent crane on Earth, being grassland endemic and preferring the shorter "sour" grasslands at higher altitudes. Known to have the smallest range size of any of the cranes, they do use small wetlands for roosting but tend to lay their eggs in secluded grasslands (no nest is built) with a 360-degree view for possible predators. The Blue Crane gathers in large flocks in the winter months, partially migrating from its breeding areas to areas where there is food and water. Flocks of non-breeders are usually around all year, including many young birds awaiting a mate and the opportunity to find a breeding site. Mainly vegetarian in diet, this grassland specialist lives on grass seeds, grain and insects, also having acquired a taste for maize and wheat – this has caused it problems in the past when farmers used to shoot Blue Cranes thought to be trampling their newly-planted crops. Threats to grasslands are increasingly impacting on this species and it is being forced to adapt to unusual, transformed habitats such as wheat and maize lands and even the fynbos of the Karoo regions. Intensification of agriculture, tourism development and industrialisation are threatening grasslands at a terrifying rate and indigenous species like cranes are being forced into smaller territories.
Breeding Blue Cranes reach maturity at the age of three to four years and once they have found a mate, they usually lay 2 – 3 large speckled eggs in a shallow, grassy depression or simply on bare ground – often on a hillside where the birds have advantage over approaching predators. In agricultural areas, they nest in pastures or in the stubble after harvest. Typical of the Blue Crane: "Perhaps as much as their regal appearance, it is the devotion of mated crane couples which has made a lasting impression on human folklore. In these birds, a pair bond once established is sundered only by the death of one of the partners. Even more remarkably, the members of a bonded pair will rarely move out of site of one another" (Tarbotan 2001). These spring and summer breeders incubate their eggs for about 30 days and will protect their young until fledging age at 3 –4 months with startling distraction displays, spreading their wings, pretending injury and attacking fearlessly predators like dogs. There are many indigenous stories about the Blue Crane: King Shaka Zulu used to boast the long black wing feathers of the Blue Crane in his regal headdress and he believed that this would give him powers to be the first to know when the rains were coming; the Zulu people would look for the Blue Crane stalking through the veld to find their cattle – Blue Cranes and cattle have a symbiotic relationship whereby the Blue Crane gathers insects and seeds kicked up by the cattle as they graze and trample the grass. Threats As already mentioned, the Blue Crane is threatened with habitat loss (grasslands mainly, and wetlands to a lesser degree) as well as management of these ecosystems: burning of firebreaks and grazing methods have to be properly controlled by the farmer if Blue Cranes are resident on his land. Powerline collisions are another prevalent threat to this blue-grey bird especially when it is flying in flocks in misty or rainy conditions. The Blue Crane now has a price on its head due to its rare status in South Africa as the national bird: recently the human threat has intensified and many Blue Crane chicks and eggs are being taken out of the wild for the international bird trade, or to keep as status symbol pets. Poisoning is another problem faced by this crane and whether deliberate for food or unintentional when secondary, this threat requires strict management of the use of agrochemicals. In the past, farmers killed cranes deliberately if they were perceived to be causing crop damage; today, farm workers often put down poisons to catch cranes or other species for extra food protein, ignorant that they are putting themselves in danger. Other threats include domestic dog predation, fences, and chicks drowning in water troughs (McCann 2002). Responses to threats With only some 25 000 Blue Cranes left in South Africa today, conservationists are increasing their efforts to understand the bird better, both biologically and geographically. An important fact regarding the Blue Crane population is that significant population losses have occurred in the natural grasslands of South Africa, with more than 50% of the species now occurring outside of this habitat. It is worrying to conservationists that the prevalence of Blue Cranes on agricultural lands is highly risky for the species as these "habitats" tend to change from one use to the next in very short periods of time – where will the Blue Crane go to next? As a result, the South African Crane Working Group (SACWG), in conjunction with the Endangered Wildlife Trust and the Conservation Breeding Specialist Group South Africa held the Blue Crane Population and Habitat Viability Assessment in Villiersdorp, Western Cape in 2002.
Crane, conservation and environmental specialists from around the country participated in this three-day workshop. The purpose of a PHVA is to help managers understand the risks facing small populations, to identify the relative importance of the factors that put a small population at risk, and to evaluate the effectiveness of various management strategies. When populations get very small, evolutionary and ecological processes change (Lacy et al 1992). The outcomes of the Blue Crane PHVA highlighted to the SACWG where they need to put their energies to "save" the Blue Crane from becoming extinct. The top five criteria are:
To date, these outcomes are being incorporated into projects and carried out by SACWG fieldworkers and other specialists in the grassland and environmental field. In addition, fieldworkers are participating in a national education and awareness programme aimed at farm workers (the eyes and ears of the land), school pupils and teachers, other groups and networks and the general public. Regular media articles and marketing drives assist with funding measures and fieldwork includes monitoring, population management, threat reduction and more. Farmers are one of the main "target groups" as very few cranes breed in reserves – most are found on private land and it is up to the landowners (our 'crane custodians') now to decide whether these birds have a future or not. "[The Blue Crane] has long loose trailing plumes that arch gracefully as they curve down to touch the ground – actually modified feathers of the inner wing that like the long tail of the widow bird may be shaken and "shimmered" like black snakes during display" (Matthiessen 2003). The three crane species of South and Southern Africa
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