In Conservation Circles, Botswana Is Considered to Be One of Africa's
Total Page：16
File Type：pdf, Size：1020Kb
view from THE TOP In conservation circles, Botswana is considered to be one of Africa’s success stories. The government is stable and has a strong conservation agenda and, particularly in the north, wildlife-based tourism is thriving. Nonetheless, for respected researcher Michael Chase, alarm bells were ringing and, as the results of an intense aerial survey show, there is every reason to be worried. TEXT BY MICHAEL CHASE PHOTOGRAPHS BY KELLY LANDEN s the scarlet sun ascends over the horizon, the drone of a small Aplane disturbs the Okavango Delta’s early morning silence. The ani- mals below are accustomed to the air traffic that ferries tourists to and from remote safari camps and pay little atten- tion, but inside the confines of the four- seater Cessna 182 there is a palpable sense of excitement. I’m part of a team that is embarking on a three-month aer- ial survey to count wildlife across north- ern Botswana’s magnificent wilderness. It is the first survey of its kind over what has long been considered one of Africa’s last wildlife strongholds, where the com- monly held perception is that elephant numbers are burgeoning and that wildlife is secure. Botswana’s conservation track record over the past 20 years has been impres- sive, a model for other countries. And yet, in reading the diaries of early explorers and biologists’ reports from the 1960s and having spent countless nights around campfires with bush-trodden madalas, I know that as little as 40 years ago thou- sands of migrating wildebeest and zebras moved seasonally between the Central Kalahari, the Makgadikgadi Pans and the Okavango Delta. Springbok, hartebeest and gemsbok grazed on extensive grass- lands in herds that numbered tens of thousands. In spite of all our conservation achievements, we simply don’t see these spectacles any more. WWW.AFRICAGEOGRAPHIC.COM 39 BOTSWANA he catastrophic crash in wildlife understand population trends. In 2004, numbers during the 1970s has however, budget constraints put paid to THE SURVEY largely been attributed to the con- these efforts and since then, debates A T Total flying time 250 hours ANGOLA ZAMBIA struction of veterinary fences, which have raged about the conservation status NAMIBIA blocked seasonal migratory routes and of wildlife, elephant numbers and the Total flight line 25 598 kilometres prevented animals from accessing food reliability of previous aerial censuses. Total area 73 478 square kilometres and water. To avoid repeating such mis- After 10 years of studying the ecology Special notes Observations of bird spe- takes, the Botswana government regular- of elephants and flying many surveys cies included wattled crane, southern ly surveyed wildlife in an attempt to over various sections of the five-country ground-hornbill, saddle-billed stork, African Kavango–Zambezi Transfrontier Conser- fish-eagle, lappet-faced vulture and Chobe NP ZIMBABWE vation Area (KAZA TFCA), I had seen bateleur. Baobab trees were assessed enough nagging signs that wildlife num- for size and possible damage. Elephant bers appeared to be declining to be con- carcasses and bones were recorded, as Okavango Delta BOTSWANA cerned. I suspected that deforestation, were environmental conditions, like the habitat fragmentation, poaching and extent of bush fires and the structural fires were playing a role, but wanted to integrity of fence lines. In the tribal grazing investigate it scientifically. Reliable es- areas, cattle were also counted. Technic- N timates of wildlife numbers based on ally robust, the survey’s ground coverage U technically robust survey methods were, sampling intensity averaged 20 per cent I believed, of paramount importance to Forest reserve in comparison to five per cent during Moremi Game Reserve previous surveys. It is the first indepen- Commercial farms Makgadikgadi Pans NP it wasn’t long before dent fixed-wing aerial survey to provide National park concession-level estimates for wildlife Pastoral/Arable/Residential Survey area the survey data and Cattle ranches International border populations in Botswana. Wildlife management area Water subsequent analyses To access the full results of the survey, began to reveal that go to www.elephantswithoutborders.org in parts of northern ANGOLA ZAMBIA B Botswana the wildlife Botswana, which relies heavily on the NAMIBIA was in trouble wildlife tourism industry for job cre- ation and foreign income. In 2010, during a meeting with the ZIMBABWE Honourable Minister of Environment, Kitso Mokaila, I was given the encour- aging news that the government would help to fund a thorough aerial count of wildlife throughout northern Botswana. Eagerly, I submitted a proposal for BOTSWANA Elephants Without Borders to take on this responsibility and in July was grant- ed permission and support to start this N seminal count. U e started flying in September, at Flight line the beginning of the dry, hot Survey area Wseason. Our altitude averaged Strata boundaries 90 metres above ground level and we International border followed straight, parallel lines or ELEPHANTS WITHOUT BORDERS (2) transects. Flying for five hours each day in cramped conditions and contending with buffeting winds, high-flying birds Each day brought fresh excitement as we ABOVE In September 2010, Elephants Without Borders and the heat take immense skill and traversed the natural splendour of Bo- undertook an aerial survey of wildlife in northern Botswana that covered 73 478 square kilometres (see map A) and concentration. Despite the challenging tswana’s ecosystems, from open grasslands, 25 598 kilometres of transects or straight lines (see map B). conditions, Mike Holding – friend, wild- woodlands and sandy ridges to wetlands, life film-maker and expert bush pilot – pans and rivers. Over some areas, we wit- OPPOSITE, ABOVE Springbok drink from an artificial waterhole in Nxai Pan National Park. The antelope did once again volunteered to help fly the nessed a seemingly never-ending panorama not fare well in the survey, with population estimates survey. Together with experienced of unique habitats, but it wasn’t long before significantly lower than those of 1996. observers Kelly Landen and Allen Bekker the survey data and subsequent analyses OPPOSITE, BELOW Recovering from precariously low we took to the skies to collect the new began to reveal that in parts of northern numbers in the 1980s, the buffalo population appears information. Botswana the wildlife was in trouble. to be stable or increasing. WWW.AFRICAGEOGRAPHIC.COM 41 29 per cent of the carcasses we recorded were located in close proximity to villages and home- steads in the Okavango Panhandle and Chobe Enclave, two areas where human– elephant conflict is known to occur 42 AFRICA GEOGRAPHIC • AUGUST 2011 WWW.AFRICAGEOGRAPHIC.COM 43 BOTSWANA CHOBE NGAMILAND CHOBE NGAMILAND CHOBE NGAMILAND 0% 0% 894% 24% 58% 20% Elephant Impala Sable 11% 6% 62% 79% 150% 83% Buffalo Kudu Tsessebe 73% 25% 97% 58% 896% 81% Eland Lechwe Warthog Giraffe 0.7% 65% 21% 96% 51% 90% Ostrich Wildebeest 5000% 344% 9.3% 28% 60% 53% Hippo Roan Zebra on lands adjacent to conservation areas. grazing area for migrating wildlife spe- Survey results for Chobe and Ngamiland showing the difference in wildlife populations between 1996 and These new data show that even cies, but the Makgadikgadi alone is too 2010. While some species, especially in the Chobe area, Botswana’s relatively well-managed pro- small to support wide-ranging ungulate appear to be stable, or even increasing, population tected areas cannot be relied on to secure populations. figures from the Okavango Delta are generally not looking as healthy as previously assumed. Unless action he Okavango Delta, wildlife numbers, as the animals’ ranges Nearly 10 years ago, the Botswana gov- is taken, these trends could ultimately have an adverse Ngamiland’s spec- 11 of 14 species often encompass land beyond their bor- ernment decommissioned portions of the effect on Botswana’s wildlife tourism industry. tacular natural counted in Ngamiland ders, where migratory habitats are being fence surrounding the adjacent Nxai Pan T centrepiece, supports a declined by an settled by people and where grazing pas- National Park to allow wildlife to move wide diversity of ante- average of 61 per cent ture has been turned into farmland. lopes, including lechwe, To examine the impact of people and waterbuck, reedbuck between 1996 and 2010 agriculture on wildlife density, we also and the elusive sitatun- surveyed the Habu tribal lands on the ga. It also serves as a tsessebe, for example, declined by 83 per western side of the delta where subsist- focal concentration area cent and warthog numbers fell by 81 per ence farming and cattle grazing occur. in the dry season, pro- cent. Even impala were down 24 per cent. Here we recorded 33 cattle – and just viding abundant water Why have large mammal populations in three wild animals – per square kilo- and food for other the delta fallen so drastically? Climatic metre. In the neighbouring Abu wildlife wildlife. As expected, variations can have a strong impact on the management area there are 40 wild ani- throughout our survey availability of water and food, which in mals per square kilometre. There is a most animals were seen turn affects population numbers. An ana- clear separation between areas of high ABOVE Cattle farming and habitat encroachment are in the delta or within 30 kilometres of a lysis of rainfall data for Ngamiland and cattle and high wildlife numbers, demon- displacing wildlife and blocking dispersal corridors. major perennial river. According to our water-flow data for the Okavango River strating that where people and livestock TOP The meandering Okavango River. Water flow rates estimates, however, 11 of 14 species showed that the severe 20-year drought, are concentrated, wildlife populations are in the river were below average during the 1980s and counted in Ngamiland declined by an which started in the 1980s, did indeed cor- lower.