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A Reassessment of the Population Size, Demography, and Status of Tanzania’s Endemic Kipunji Rungwecebus kipunji 13 Years on: Demonstrating Conservation Success

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Tim R. B. Davenport
Tim R. B. Davenport
Tim R. B. Davenport
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Sophy J. Machaga
Sophy J. Machaga
Sophy J. Machaga
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Noah Elias Mpunga at Wildlife Conservation Society
Noah Elias Mpunga
Sylvanos P. Kimiti
Sylvanos P. Kimiti
Sylvanos P. Kimiti
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Long-term population data on endangered species are fundamental to measure conservation implementation objectively, but they are rare, especially in remote forest locations and with total counts. Following the scientific description of the kipunji (Rungwecebus kipunji), we implemented a range of long-term conservation interventions. Thirteen years later, we reassess with a complete count the population size, demography, and distribution of R. kipunji in Tanzania’s Southern Highlands, employing the identical sweep census methods across 1,428 km. We also monitored a habituated group daily over the same period. We report a total of 1,866 individuals in 59 groups (μ = 31.63 ± SE 1.2) in Livingstone Forest (within Kitulo National Park), Mt Rungwe Nature Reserve, and Madehani Village Forest. We estimate a 65% increase in individuals, a 59% increase in group numbers, and a 19% increase in area of occupancy (AoO). Mean group sizes were similar in Mt Rungwe (32.9) and Livingstone (31.9), but lower in the unprotected Madehani (24). The ratio of adult females to adult males was significantly higher in Mt Rungwe than Livingstone. The ratio of subadults/juveniles to adult females, a proxy for survival, was good (1.77), but higher in Livingstone (2.61) than Mt Rungwe (1.11). In the habituated group, we recorded a 121% increase in group size. Signs of human activity fell by 81%, with a 100% and 98% reduction in the number of charcoal pits and timber felling, respectively, in Mt Rungwe. Both temporal and spatial data demonstrate that long-term holistic conservation leads to increased primate numbers.
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Vol.:(0123456789)
https://doi.org/10.1007/s10764-022-00281-3
1 3
A Reassessment ofthePopulation Size,
Demography, andStatus ofTanzania’s Endemic
Kipunji Rungwecebus kipunji 13 Years on:
Demonstrating Conservation Success
TimR.B.Davenport1 · SophyJ.Machaga2· NoahE.Mpunga2·
SylvanosP.Kimiti2· WillyMwalwengele2· ObadiaMwaipungu2·
PascalM.Makumbule3
Received: 19 October 2021 / Accepted: 20 January 2022
© The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature
2022
Abstract
Long-term population data on endangered species are fundamental to measure conserva-
tion implementation objectively, but they are rare, especially in remote forest locations
and with total counts. Following the scientific description of the kipunji (Rungwecebus
kipunji), we implemented a range of long-term conservation interventions. Thirteen
years later, we reassess with a complete count the population size, demography, and dis-
tribution of R. kipunji in Tanzania’s Southern Highlands, employing the identical sweep
census methods across 1,428 km. We also monitored a habituated group daily over the
same period. We report a total of 1,866 individuals in 59 groups (μ = 31.63 ± SE 1.2)
in Livingstone Forest (within Kitulo National Park), Mt Rungwe Nature Reserve, and
Madehani Village Forest. We estimate a 65% increase in individuals, a 59% increase
in group numbers, and a 19% increase in area of occupancy (AoO). Mean group sizes
were similar in Mt Rungwe (32.9) and Livingstone (31.9), but lower in the unprotected
Madehani (24). The ratio of adult females to adult males was significantly higher in Mt
Rungwe than Livingstone. The ratio of subadults/juveniles to adult females, a proxy for
survival, was good (1.77), but higher in Livingstone (2.61) than Mt Rungwe (1.11). In
the habituated group, we recorded a 121% increase in group size. Signs of human activ-
ity fell by 81%, with a 100% and 98% reduction in the number of charcoal pits and tim-
ber felling, respectively, in Mt Rungwe. Both temporal and spatial data demonstrate that
long-term holistic conservation leads to increased primate numbers.
Keywords Census· Conservation· Endangered· Rungwecebus kipunji· Primates·
Tanzania
Handling Editor: Joanna Setchell
Extended author information available on the last page of the article
International Journal of Primatology (2022) 43:317–338
/Published online: 9 February 2022
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
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