Phase Two of the 2024-2025 National Wildlife Census in Amboseli-Magadi Ecosystem

The 2024-2025 National Wildlife Census was launched and completed in the Mara ecosystem, Narok County, in June 2024. The second phase of the census commenced in the 14,000 km2 Amboseli-Magadi ecosystem on 8th July, 2024, with a view to ascertain Kenya’s total wildlife populations, taking into account the vagaries wrought by the prolonged 2022 drought.

The world is driven by data; almost all decisions are made based on information. Effective conservation can only happen when protected area managers know exactly what they are managing. Conducting regular wildlife censuses – such as the triennial National Wildlife Census, ensures that data collated from the exercise will be a thermometer for the efficacy of Kenya’s conservation efforts.

The methodologies employed in the census include:

• Total aerial census
• Total ground census (individual identification – vehicles and road networks, artificial intelligence)
• Sample aerial census (conventional SRF, oblique camera, AI)
• Sample ground census (camera traps, spatially explicit capture recapture, call back, spoor counts, mark--recapture techniques, citizen science)
• Bioacoustics methods (bats and marine)
• Under Water Visual Census (UWVC) – point intersect, line transect and quadrant
• Remote sensing data for vegetation/land cover
• The Earth Ranger system, which employs smartphones.

For aerial survey, the census area is sectioned into blocks (the largest of which is 600 km2) with a recommended North-South transects orientation. Each aircraft is assigned one block per day, in two sessions. Recommended flight height is 300 feet above ground; speed limit is 180 km/hr. Pilots are accompanied by Front Seat Observers (FSOs) and Rear Seat Observers (RSOs) for maximum accuracy in data capture. The pilot is required to circle any observation whenever prompted to do so by the observers and all take off, start count, end count and landing times must be captured. FSOs and RSOs use requisite codes to capture data into Dictaphones, such as BN (baboon), EL (elephant), ED (eland), GN (gerenuk), GR (giraffe), APW (artificial water pan wet), and so forth, in keeping with the “complete cover approach,” which targets species numbers and locations, as well as human activities such as settlements, livestock, charcoal kilns, fences, logging and the like.

The pilot searches each block along predetermined regular straight transects as per the flight plan, flying at least one kilometre past the edge of an assigned block. GPS record the exact flight pattern and spatial information of all observations, while Dictaphones and cameras capture the attribute data. Transect width of 1km is used (500m either side) for total count, while irregular transects are flown on hills. Upon landing, dictaphone data are downloaded and transcribed into the database, after which GPS data (tracks and waypoints) are downloaded and merged with transcribed voice data. The resulting data undergoes cleaning to check data integrity, completeness, processing and handling for identification and elimination of possible double counts, before data analysis and reporting is done. Subsequent decisions taken by management are based on the quality of data captured, which highlights the importance of the entire exercise being conducted with precision.

Data collection teams should be well versed in animal identification and the ability to count with confidence. For instance, there are several species of antelopes, such as gerenuk, eland, Thomson’s gazelle, Grant’s gazelle, impala, lesser kudu, dikdik and topi. These teams are also required to have expert knowledge of equipment operation as well as cabin procedures. On their part, the data management teams should be grounded in equipment operation and management, data downloading and data handling – transcription and typing accurately.

Special emphasis is given to elephant numbers, given that their population plummeted from approximately 160,000 in the 70s, to 16,000 in the 90s. As such, elephants are counted even when not alive – any carcasses sighted are recorded thus: fresh and recent carcasses (death within a period of less than a month, to six months old) which must be immediately reported to ground teams and investigated.

Aerial censuses cover massive acreage which rangers may not have patrolled; however daily ground monitoring provides more comprehensive data than aerial counts, in terms of age, gender and cause of death of any carcasses seen. There are also classifications for recent carcasses, old, and very old carcasses. Experts are able to ascertain the age of an elephant carcass by examining the surroundings in which the carcass is located, as well as the condition of the carcass. The environment also affects the deterioration of a carcass, e.g.one in Tsavo will decompose much faster than one in a forested area. 

Carcasses spotted via aerial census are analysed via a carcass ratio formula, which is:  Dead elephants/Total number of carcasses plus living elephants. Aerial data on elephant mortality therefore greatly supports ground monitoring programs. Population trends are closely monitored to ascertain any increases, decreases or stagnation, where after immediate remedial actions are implemented.

The real-time Earth ranger technology was employed for the first time during this leg of the census, although it has been employed in recording patrol efforts (time spent, distance covered) of ground teams. Earth ranger captures data such as census ID, names of the data collection crew, census block covered, start and end count and flight times. GPS was used prior to capture similar data, but it was not possible to segment some of the key data sets. For instance, the time spent between a plane taking off and reaching the start of the census block (transit time) is unaccounted for - no searches for data occur and no recording is done if sightings are made. In addition, Earth ranger indicates the ‘unused’ time from when the data recording stops, to the time the plane embarks on landing. It is conceivable that when Earth ranger is fully developed, it will replace the GPS for tracking. Artificial Intelligence (AI) and drones are also envisioned for use in future censuses, whereby cameras will be fixed onto planes without observers.

This second phase of the census is expected to take five days, and involves myriad partners, including the Ministry of Tourism and Wildlife, Directorate of Resource Surveys and Remote Sensing (DRSRS), WWF, Big Life Foundation, Stand Up Shout Out (SUSO), Lion Guardians, Giraffe Conservation Foundation (GCF), Amboseli Elephant Trust, International Fund for Animal Welfare (IFAW), South Rift Association of Land Owners (SORALO), a Soysambu guest crew which included Mr. Bongo Woodley (former KWS Warden), and several other benefactors.

Other censuses are being conducted concurrently with the 2024-2025 National Wildlife Census, such as helicopter counts in Mwea National Reserve, Solio Rhino Sanctuary, Ruma and Lake Nakuru National Parks, among other rhino sanctuaries. Water fowl counts will also be done in the Amboseli ecosystem wetlands, in addition to large carnivore counts (lions, hyenas, jackals).

The next leg of the census will cover the Athi-Kapiti ecosystem.