Shoebill (Balaeniceps rex)
|Also known as:||Whale-headed stork|
|French:||Baléniceps rois, Bec-en-sabot|
|Size||Height: 115 - 150 cm (2)|
Body length: 100 – 120 cm (2)
|Weight||4 – 7 kg (2)|
Classified as Vulnerable (VU) on the IUCN Red List 2006 (1), listed on Appendix II of CITES (3), and listed under Annex II of the African-Eurasian Migratory Waterbird Agreement (4).
The unmistakable, prehistoric-looking shoebill is one of the most impressive birds to be found in Africa. A mysterious inhabitant of impenetrable marshes, this tall wading bird possesses a bluish-grey plumage, long black legs, broad wings and muscular neck, but is undeniably dominated by its fantastically unique ‘shoe-like’ bill, from which its common name derives. This imposing greenish-brown bill is huge and powerful at a remarkable 23 cm long and 10 cm broad, ending in a ferociously sharp nail-like hook (5). The eyes are a pale yellow and at the back of the head exists a small hood of feathers (2). Primitive in appearance, the bird has baffled taxonomists over its affinities, showing similarities to storks, pelicans, hamerkop and herons in some respects, yet remaining different in others. Indeed, the shoebill's defiantly unusual appearance indicates how much it has evolved to occupy a highly individual niche, and one which happens to tie it to some of the most inaccessible habitat in the world (5).
Broken distribution in tropical east Africa from Sudan and western Ethiopia to Zambia (6) (7).
Found in extensive papyrus grass and reed swamps and seasonally flooded marshes with floating vegetation, preferring those formed by papyrus (6) (8).
A predominantly solitary species, in which adults come together only to breed. The breeding season is ill-defined, but some evidence suggests that it coincides with the onset of the dry season (5), to prevent flooding of the nests (2). One to three eggs are laid in large flat nests built amid swamp grasses (5), and incubated for approximately 30 days (7). Young can stand only after two and a half months, and are able to hunt after three and a half, but remain dependent on their parents for food until somewhat older (2). It takes three to four years for young to become sexually mature (5) and individuals have been known to live 36 years in captivity (9).
The shoebill usually feeds at night (7), hunting chiefly by ambush, standing motionless waiting for prey, then attacking with remarkable speed and power (5). Prey is grasped from the water in the bird’s sharp, hooked beak, which grips, crushes and pierces in one instant. African lungfish are common prey, alongside a variety of smaller and larger fish, amphibians, water-snakes, lizards, turtles, rats, young waterfowl and even young crocodiles (5).
Although widespread, the shoebill is considered uncommon, with a total world population estimated at 5,000-8,000 (10). The small population is declining due to habitat destruction and degradation, nest disturbance, increased hunting levels and capture for the bird trade. Fire and drought threaten habitat in Zambia, nests are trampled by large herbivores feeding in swamps, and there is some evidence for trapping and persecution. Conflict in Rwanda and the Democratic Republic of Congo has disrupted some protected areas (e.g. Akagera National Park) that support the species, and the proliferation of firearms has greatly facilitated hunting of this bird. Destruction of papyrus swamps by cattle and fire also endanger the shoebill in its stronghold, Sudan. The area of Sudd swamps of southern Sudan almost trebled between 1952 and 1980, but this habitat is now threatened by its potential further drainage to facilitate renewed prospective plans for the Jonglei Canal (6). The current status of shoebills in the Sudd is unclear.
International trade in the shoebill is limited by the species’ listing on Appendix II of the Convention on International Trade in Endangered Species (CITES) (3). However, trade does still occur, and this certainly poses an unwelcome pressure to already-dwindling populations. Plans are underway to upgrade the shoebill to Appendix I of CITES, which would render all trade illegal (11). This bird occurs in a number of reserves, although some of these are inadequately protected or have been given up after political unrest (8). The key site in Tanzania, the Moyowosi/Kigosi/Ugalla complex has a population of a few hundred individuals, and part of the area was designated as the country's first Ramsar Site in 2000 (12). The key site in Zambia, Bangweulu Swamps, is also a Ramsar Site (11). The Ramsar Convention on Wetlands is an international treaty for the conservation and sustainable utilization of wetlands, which aims to stem the progressive encroachment on and loss of wetlands, recognizing their fundamental ecological, economic, cultural, scientific, and recreational value (13). Uganda attaches economic value to the shoebill, which is an important asset for ecotourism in the country (11). A few injured birds are generally housed at the Kampala Zoo, some of which were confiscated from trappers and fisherman by the government (14). It has been suggested that a future priority for this bird might be to create community-based environmental awareness programmes focussed on generating national pride in the shoebill to discourage hunting (6). Indeed, recognition of the shoebill as one of the great African species can only serve to aid conservation efforts to save this unusual and cherished bird (5). It is also a priority to determine its current status in the extensive swamps and floodplains of southern Sudan, and to put an end to the live trade of this globally threatened species (11).
For further information on the shoebill see:
African Bird Club: Working for Birds in Africa:
Authenticated (03/07/2006) by Tim Dodman, Associate Expert, Wetlands International.
IUCN Red List (June, 2006)
FSBio – Hannover (December, 2005)
CITES (November, 2005)
UNEP-AEWA (November, 2005)
African Bird Club: Working for Birds in Africa (December, 2005)
BirdLife International (December, 2005)
Tierseiten (December, 2005)
Zoological Museum Amsterdam (December, 2005)
Max Planck Institute for Demographic Research (December, 2005)
- Dodman, T. (2002) Waterbird Population Estimates in Africa. Consultation Draft, Wetlands International.
- Dodman, T. (2006) Pers. comm.
- Dinesen, L. and Baker, M. (2006) Status of Shoebill Balaeniceps rex in Malagarasi, Tanzania. Bull ABC, 13(1): 37 - 44.
Wikipedia: The Free Encyclopedia (December, 2005)
Creagrus (December, 2005)