Giraffe in decline
Giraffe in decline
BY KYLIE McQUALTER
As the sun descends below the palm tree-silhouetted horizon, the clouds bathed in hues of luminous pink and orange, and the sound of the hippo’s wheeze-honking territorial warnings echoes across the swamps and floodplains of the delta, a huge, handsome, giraffe bull (ID -M0005ABU) strips a Kigelia africana tree of all its low hanging, fresh, young fruits – a favourite food item, although only reachable by the tallest of individuals.
His GPS location has already been recorded and photo taken for identification using his unique coat pattern as a natural marker – ideal for photographic mark-recapture work. If he had companions with him, they too would be recorded, but this evening, he’s on his own. This giraffe is just one of the 149 individuals identified so far as part of the giraffe research being conducted in wildlife concession NG26 in the Okavango Delta. Another 566 have been identified on the Chobe riverfront area and surrounds.
The study, examining the density and distribution, demography, ecology, behaviour and social organisation of giraffe populations occupying these two vastly different environments within northern Botswana is a collaborative research initiative between Elephants Without Borders, the Giraffe Conservation Foundation and the University of New South Wales, and falls under the umbrella of EWB’s Large Herbivore Ecology Programme.
With a massive decline in giraffe numbers across sub-Saharan Africa over the last decade and a half, and population estimates halving in Botswana in this same time, research into this iconic species has never been more crucial. Only by having baseline knowledge of the biology and ecology of giraffes in this country can we really begin to understand why their numbers are decreasing and, if possible, do something about it.
Already, data obtained from movement studies of the Chobe giraffe is showing that they appear not to travel impressively long distances as has been found for other large herbivores such as the elephant, zebra and buffalo but rather, their ranges are on a much smaller scale. The largest female giraffe range recorded was just over 500km2, compared with 3,000-19,000km2 for that of a female elephant.
Their eclectic diets and ability to access forage well above heights reachable by most other browsers, means that interspecific competition (competition between different species) for these resources is largely reduced. As such, their ranges are more likely influenced by intraspecific competition (competition within the same species) and location and availability of preferred forage species.
The importance of neighbouring forest reserves as both corridors and as foraging areas has also been shown. Several giraffes have been found to move from Chobe National Park, through the Kasane Forest Reserve and into Zimbabwe. Such information is relevant to authorities considering the de-gazetting of forest reserve land for example, and emphasises the importance of maintaining cross-border links between parks and reserves.
As with the movement data, collection of population, behavioural and social data continues, revealing more about this little-studied, charismatic species. Being the first of its kind in Botswana, this study will also provide the baseline information essential for development of a conservation management strategy for giraffe in the country. By implementing conservation measures, we might just help ensure that Botswana remains one of Africa’s remaining giraffe strongholds.
FACT FILE: GIRAFFE
Scientific name: Giraffa camelopardalis
Population estimate: < 80,000
Height (average adult): Male – 5.3m (17ft 4in)
Female – 4.3m (14ft 2in)
Weight (average adult): Male – 1,200kg (2,600lb)
Female – 830kg (1,800lb)
Height & weight at birth: Just under 2m; approx 100kg
Longevity: +/- 25 years
Gestation: +/- 15 months
Speed: 50km/h for prolonged periods; up 60km/h at top speed
More from this issue:
Zambezi Traveller (December 2013)
More from the Zambezi Traveller:
Chobe Destination Profile