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Crane species in Namibia. Blue crane ( Anthropoides paradiseus ) Wattled crane ( Grus carunculatus ) Grey crowned crane ( Balearica regulorum ). Blue crane. Distribution and abundance - overall
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Crane species in Namibia Blue crane (Anthropoides paradiseus) Wattled crane (Grus carunculatus) Grey crowned crane (Balearica regulorum)
Blue crane Distribution and abundance - overall • Smallest range of all the world’s cranes - endemic to southern Africa with most of its range falling in South Africa • Total population of approx 20,000 • Three separate sub-populations with no movement between them • Utilises grasslands and pans, croplands, pastures • Feeds on seeds and flowers from grasses, frogs, reptiles, fish, insects • Egg-laying between August and April, mainly September – January • Often forages alongside Grey crowned and Wattled cranes • Threats include poisoning, collisions with power lines, habitat loss to urbanisation, afforestation and crop farming
Blue crane In Namibia: • No evidence of movement to/from Etosha population • Only found in dry and wet grasslands and pans in Etosha NP and grasslands immediately north, mainly in the wetter areas of this region and associated with perennial springs and isolated waterholes • A survey in the late 80’s estimated not more than 80 birds; a follow-up survey in 96 estimated a maximum of 60 birds suggesting a possible 25% decline in 6-8 years • Distributed in pairs or trios but groups of up to 30 birds sometimes occur • Single most important site where birds assemble to roost is Andoni water hole • Egg-laying between December and March, peak in February, 1 – 3 eggs.
Distribution of Blue crane in relation to protected areas and conservancies
Blue crane – potential for range expansion? Population density Vegetation Livestock density
No of birds recorded in Wetland counts: Blue crane * Aug 91: Includes Oshituntu
Number of nest record cards: Blue crane(33 records, between 1970 and 2000)
Blue crane Red Data status – Critically Endangered in Namibia – population declining Threats Declining in Etosha. Why? • low rainfall • expanding human populations in northern Namibia • encroachment of local people with cattle into grasslands north of Etosha • snares, collisions with power lines • borehole drilling in the north may reduce permanence of Etosha’s springs • genetic inbreeding Actions • 5-yearly total population assessments • Maintain water levels at critical waterholes (e.g. Andoni and Twee Palms) • Investigate genetic status • Colour-ringing study to determine survival, movements and habitat use
This presentation was compiled using information and data from: • The Atlas of Southern African Birds (Ed. Harrison et al, 1997) • Avifaunal Database of Namibia, held at the Directorate of Environmental Affairs, MET • Atlas of Namibia – A Portrait of the Land and its People (Mendelsohn et al, 2002) • An environmental profile and atlas of Caprivi (Mendelsohn et al, 1997) • Draft text from the Red Data Book on birds of Namibia (Simmons, in prep)