The recently released Kavango Zambezi Transfrontier Conservation Area (KAZA TFCA) Survey report has recorded the highest elephant carcass ratios for Botswana, an indication of a high elephant mortality rate that needs further investigation.
The report, launched last week in Livingstone Zambia, follows the KAZA Elephant Survey (2022) which commenced in August 2022 and was completed in October 2022.
The primary objective of the survey was to obtain a relatively precise and accurate estimate of the number of African savanna elephants (hereafter elephants) in the Kavango Zambezi Transfrontier Conservation Area (KAZA TFCA), by synchronising data collection, particularly in areas of transboundary elephant movement. Secondary objectives included estimating populations of elephant carcasses and other large herbivores (both wild and domestic), as well as recording their spatial distribution.
In the estimated elephant carcasses of 26641 reported in KAZA, Botswana is reported to have recorded 19371 estimated, followed by Zimbabwe with 5166, Angola 1163, Namibia 780 and lastly Zambia with 137 cases.
According to the survey, Botswana was estimated to have recorded a ratio of 0.72% of fresh and recent carcass from the elephants that have died in the 12 months prior to the 2022 survey. The country further reported an all carcass ratio of 12.80%. The report has stressed a that in Botswana the fresh and recent carcass ratio increased from 0.1% in 2014 to 0.70% in 2018 and remained at a similar 0.72% in 2022.
Generally, the report indicates that there is a concentration of fresh and recent carcasses in the border region between Botswana and Namibia along the Kwando-Linyanti-Chobe River system.
Presenting the report, the Survey Coordinator Darren Potgieter stressed that the notable increase in carcass numbers observed in Botswana presents a challenge in interpretation and the phenomenon is likely as a result of several factors.
Among them, he said there might have been an actual increase in mortality rates in the past and secondly there may be improved detection of carcasses due to the implementation of a narrower search strip compared to previous surveys. He added that the broader survey coverage, particularly in predominantly wet-season habitats, would have contributed to additional carcasses observed.
“To gain a comprehensive understanding of the underlying causes for this phenomenon, a more in-depth analysis is required. Further investigation should focus on examining the individual and combined impacts of these factors on the observed increase in carcass numbers,” he said.
According to him, the Botswana’s Department of Wildlife and National Parks was informed of the high number of fresh carcasses seen during the survey, and an investigation into the causes of death is on-going. He noted that based on the ground investigations, poaching has been ruled out as the principal cause as the tusks on the carcasses were found to be intact.
“The underlying reasons for high mortality rates could be diverse and are likely to be a combination of several factors such as of poaching, habitat loss and associated human-elephant conflict, disease, and other natural causes. For the conservation of elephants, a priority is to carry out further investigations to identify the drivers of the high mortality rates and to ensure that appropriate interventions are implemented,” he said.
For her part, Botswana’s minister of Environment and Tourism Phildah Kereng raised concern about the high elephant carcass ratio. She said it is crucial for the research institutions to interrogate the data for what accounts for the spatial distribution and numbers of the carcasses, in efforts to then guide policy makers and practitioners through evidence-based research.
She stated that both individual nations and as a collective must commit to addressing the underlying challenges by rigorously implementing recommendations of the survey, and those from ensuing research based on the survey data launched.
Meanwhile the survey found that the overall elephant population in the KAZA TFCA is stable. This is compared to the results of the 2022 survey and those of recent surveys.
The results show a total population of elephants in KAZA TFCA to be at 227 900: with Botswana leading with 131 909 elephants followed by Zimbabwe with 65 028, then Namibia with 21 090, Angola with 5 983 and lastly Zambia with 3840.
The report further highlights that the distribution and density of elephants during the survey confirms the ecologically anticipated pattern of higher density and aggregation near permanent water sources like the Okavango and Chobe-Linyanti-Kwando River systems, as well as in parts of northwestern Matabeleland, where artificial water supplies are widely available in Hwange National Park.
Conversely, the density of elephants is reported to be lower in regions with less water, this is also attributed to the distribution of elephants in relation to cattle and human settlements, revealing a pattern of spatial segregation between elephants and the presence of humans and livestock.