In response to the ongoing crisis in Tanzania, the government of Tanzania is co-sponsoring a new survey of the Ruaha-Rungwa ecosystem in collaboration with Tanzania National Parks, Wildlife Division, the Ngorongoro Conservation Area Authority, Frankfurt Zoological Society and the Wildlife Conservation Society.
How do we know our elephant counts are accurate? The answer is a proven scientific process, rigorous training, and careful application of technology applied consistently across all survey teams.
Survey teams for the Great Elephant Census came together before any surveys were made to discuss standards and training, and to identify ways to improve survey methods using technology.
One bit of technology the surveyors desired was a better way to keep track of flight altitude and speed. Fly too high or too fast and they are likely to under count the elephants; fly too low or too slow and there is a risk of over counting. They sought a device that would make it easier track flight speed and ensure altitude was right.
To address this need, engineers at Vulcan Inc., Paul G. Allen's company, developed and built a simple, inexpensive survey data logger to help pilots stay on track and to record the data scientists need to calculate the count post-survey.
The data logger is built from mostly off-the-shelf parts, including a consumer tablet that serves as the screen and input method. An app written by Vulcan engineers supplies the brain. Custom mounting brackets created using a 3-D printer attach the tablet to the logging unit, making the whole package able to tolerate the rough operating environment of wildlife surveys.
Six data loggers have been delivered to survey teams already, with several more on the way. Vulcan engineers and Howard Frederick, one of the survey scientists, recently met in Seattle to discuss upgrades to the data logger based on feedback from the field. Howard shared his excitement about data logger as an important tool for improving the accuracy of the Census. The entire team is dedicated to helping produce the best possible Census data.
‘Good to go!’ said the email’s subject line. And so, just two mornings later -- three days before the end of June -- we were going, speeding down the airstrip in a small two-seater plane. After eight months of scheming and planning, plus a thousand emails, the 2014 national survey of the African elephant in Zimbabwe was starting.
As the plane lifted off and banked, Makuti lay to the left. This small place -- far too small to be called a town -- marks a T junction in the tar road: north to Chirundu and Zambia, or west to Lake Kariba. Its only petrol station had closed three weeks earlier. As the plane headed south, Makuti -- located on high ground amongst the hills of the Zambezi escarpment in northern Zimbabwe -- was most noticeable for its mobile phone towers and very tall radio masts (‘jammers’ someone had said). Such structures are a relatively new hazard to low-flying aircraft during elephant surveys – phone towers did not exist when I first flew wildlife surveys in Zimbabwe.
Most aerial surveys of elephants involve flying long, straight flight lines at low-level. But that was not safe in this hilly terrain. Here we used a different approach. First, on a map, the area was divided into blocks, defined using rivers, vehicle tracks, or watersheds as boundaries. Then we selected at random some of the blocks and these were ones that we now searched for elephants.
A few days later, I handed over the role of recorder/observer to Greg. I had to return to town and organise logistics for the next stages of the programme: surveys of the elephants in Gonarezhou NP in the southeast lowveld and over the floor of the Zambezi Valley, just north of the hills that we were flying now.
Once back in town, I wanted to buy more drums to transport avgas to the remote airstrips that the aircraft will use during the surveys. New, lined drums reduce the risks of fuel being contaminated. Economists may regard globalization as a good thing, but the disadvantages are immediately clear to me: there is a workers’ strike at the South African factory that makes the sheet metal which the Zimbabwean company imports to manufacture new drums. Hence, no new drums are available and no one knows when they will be. We will have to come up with another plan for fuel. And I need to import those fancy filters to make doubly-sure that no contaminated avgas goes into the plane.
It is now the beginning of August and the survey programme has moved to Gonarezhou. Here we will fly those long straight transects. But first we must calibrate the width of the search strips. We fly backwards and forwards across the airstrip, with metre-high numbers, ten metres apart, aligned along the edge of the strip. For each pass over the strip, I note the aircraft’s height above the ground from the radar altimeter. Radar altimeters are essential for transect surveys (we can calculate the width of the search strips only if we know the aircraft’s height above the ground). But they are also notorious amongst survey biologists for being expensive and temperamental. And so it proves today. We need to adjust the rods attached to the wing struts to demarcate those search strips. We land and taxi towards the hangar and the spanners. Suddenly the altimeter display goes blank. No amount of fiddling with fuses returns it to life. Very soon, the sun sets and we head back to camp.
In the middle of the night, some elephant bulls wander through camp, weaving round the tents. In the past, Gonarezhou’s elephants had a reputation for being aggressive, but no more. We assumed that these bulls were the same ones that approached camp earlier during the day. They had walked past Fay as she stood on the edge of camp, phone to ear, searching for a better mobile signal.
The next morning, more fuse-fiddling and even a test flight failed to return life to the altimeter. We consulted Olivia, ZimPark’s chief ecologist (easy to do, she was staying in the next-door tent). We rescheduled the survey for October. For me, it is back to town again. We need a substitute for that radar altimeter – we need a laser rangefinder. Once we obtain one, we will need to commission a custom bracket to attach it to a wing strut. And of course there will have to be a test flight. All within the two weeks before the start of the next survey – two weeks which would be divided by a four-day holiday weekend.
- Kevin from the Zimbabwe survey team
But now as we prepare to take part in the Great Elephant Census, a different type of flying will be our routine for the next couple of weeks. The flying we will do will require us to fly slow (around 110 miles per hour) and close to the ground (350 feet above ground level) in order to survey every elephant and buffalo in the Serengeti Ecosystem. This type of count is referred to as a total count and requires us to fly transects 500 metres apart, allowing for every animal to be accounted for.
We have rolled out 80 drums of AVGAS –16,000 litres that will fuel three small aircraft. One Cessna 206 and two Cessna 182’s. Together, 260 hours of flying will ensure we cover the entire Serengeti Ecosystem (30,000 square kilometres). For the next two weeks, we will wake up at 6 a.m. to depart while the temperature and winds are mild and visibility is the best. We fly up to 8 hours every day. After the flying is completed, all the data needs to be recorded and entered into the system. By the end of the day we feel exhausted, hungry and dehydrated, but also proud to look back and see how much we have flown -- and in the end, proud to be a part of saving Africa's elephants.
Organizing and preparing for a large survey like the Pan African Elephant Aerial Survey in Tanzania is a substantial challenge. The fuel has traveled from South Africa into the port at Dar es Salaam, before being trucked to Mwanza in northwestern Tanzania and finally across the last stretch of dirt road to get to our base in Serengeti National Park.
Three pilots, three front seat observers, six rear seat observers, three data management personnel, and three supervision observers make up the team – most having traveled several hundred kilometers to reach our base. The survey crew consists of professionals from many different organizations including Tanzania National Parks, the Wildlife Division of Tanzania, the Tanzanian wildlife research centre, the Ngorongoro conservation area authority and Frankfurt Zoological Society, not to mention independent consultants bringing in specialized expertise. Over the next couple weeks, they will all need to be housed and fed and looked after appropriately, as our work ahead is arduous.
Our crew was trained and carefully selected from a team of experts including Dr. Simon Mduma, Dr. Mike Norton Griffith, Dr. Ian Douglas Hamilton and Mr. Howard Frederick. Together we counted the Selous Ecosystem in 2013 and we are confident that our foundation is a strong, professional and trusted crew. They make up the heart of this count!
African wildlife and wilderness drive the passion behind my work. With a concern for conservation of earth’s wild places I enjoy flying over these places and contributing to survey these areas. With over 3,000 hours of bush flying and survey flying under my belt, I love the simplicity of small bush aircraft and the work that can be done with them.
I count the wildebeest migration every 2-3 years, and have also taken part in many Surveys across Tanzania.
The meeting I attended last week in Kasane, Botswana, was focused on coordinating efforts across the KAZA Transfrontier Conservation Area to count this special elephant population. Because so many elephants live in the region and conservation efforts are carefully organized, the teams wanted to ensure there are no barriers to their passage between countries. Delegates from each of the five countries in the region -- Namibia, Angola, Zambia, Botswana and Zimbabwe -- attended. There are more than a dozen national parks in the region. The group posed for a photo at the end of a successful workshop.