Demography of a forest elephant population
Open accessAbstract
African forest elephants face severe threats from illegal killing for ivory and bushmeat and habitat conversion. Due to their cryptic nature and inaccessible range, little information on the biology of this species has been collected despite its iconic status. Compiling individual based monitoring data collected over 20 years from the Dzanga Bai population in Central African Republic, we summarize sex and age specific survivorship and female age specific fecundity for a cohort of 1625 individually identified elephants. Annual mortality (average = 3.5%) and natality (average = 5.3%) were lower and markedly less variable relative to rates reported for savanna elephant populations. New individuals consistently entered the study system, leading to a 2.5% average annual increase in the registered population. Calf sex ratios among known birth did not differ from parity. A weak seasonal signal in births was detected suggesting increased conceptions during the wet season. Inter-calf intervals and age of primiparity were longer relative to savanna elephant populations. Within the population, females between the ages of 25-39 demonstrated the shortest inter-calf intervals and highest fecundity, and previous calf sex had no influence on the interval. Calf survivorship was high (97%) the first two years after birth and did not differ by sex. Male and female survival began to differ by the age of 13 years, and males demonstrated significantly lower survival relative to females by the age of 20. It is suspected these differences are driven by human selection for ivory. Forest elephants were found to have one of the longest generation times recorded for any species at 31 years. These data provide fundamental understanding of forest elephant demography, providing baseline data for projecting population status and trends.
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Female elephants can continue to reproduce up into their 60s.
“females can continue to reproduce up into their 60s (Lahdenperä et al., 2014; Moss, 2001; Turkalo et al., 2018).”
From Do elephants really never forget? What we know about elephant memory and a call for further investigation (2025) · cites this paper as Turkalo et al., 2018
The Results section (‘Fecundity and reproductive value’; page not provided) reports births among females older than 49, but the oldest female observed giving birth was 59. It therefore supports reproduction into the late 50s, not the specific claim that females reproduce in their 60s. (LLM, conf=0.87)
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Cites
The Evolution of Life-histories
Benton, T. G., & Stearne, S. C. (1993) · Journal of Animal Ecology · doi:10.2307/5403 · Cited by 12,192 · see citing works
Program MARK: survival estimation from populations of marked animals
White, G. C., & Burnham, K. P. (1999) · Bird Study · doi:10.1080/00063659909477239 · Cited by 7,631 · see citing works
The evolution of life histories: theory and analysis
(1993) · Choice Reviews Online · doi:10.5860/choice.30-4983 · Cited by 3,417 · see citing works
The Evolution Of Life Histories
Stearns, S. C. (1998) · doi:10.1093/oso/9780198577416.001.0001 · Cited by 2,384 · see citing works
Program MARK : survival estimation from populations of marked animals
Gc, W. (1999) · Bird Study · Cited by 1,972 · see citing works
Quantification of Extinction Risk: IUCN's System for Classifying Threatened Species
Mace, G. M., Collar, N., Gaston, K. J., Hilton‐Taylor, C., Akçakaya, H. R., Leader‐Williams, N., Milner‐Gulland, E. J., & Stuart, S. N. (2008) · Conservation Biology · doi:10.1111/j.1523-1739.2008.01044.x · Cited by 1,403 · see citing works
ESTIMATING ABUNDANCE FROM REPEATED PRESENCE–ABSENCE DATA OR POINT COUNTS
Royle, J. A., & Nichols, J. D. (2003) · Ecology · doi:10.1890/0012-9658(2003)084[0777:eafrpa]2.0.co;2 · Cited by 1,364 · see citing works
Population dynamics of large herbivores: variable recruitment with constant adult survival
Gaillard, J., Festa‐Bianchet, M., & Yoccoz, N. G. (1998) · Trends in Ecology & Evolution · doi:10.1016/s0169-5347(97)01237-8 · Cited by 1,346 · see citing works
Genetic monitoring as a promising tool for conservation and management
Schwartz, M. K., Luikart, G., & Waples, R. S. (2006) · Trends in Ecology & Evolution · doi:10.1016/j.tree.2006.08.009 · Cited by 1,226 · see citing works
Clutton-Brock, T. H., & Sheldon, B. C. (2010) · Trends in Ecology & Evolution · doi:10.1016/j.tree.2010.08.002 · Cited by 977 · see citing works
Wildlife Ecology and Management
Wolff, J. O., Caughley, G., & SINCLAIR, A. R. E. (1995) · Journal of Animal Ecology · doi:10.2307/5904 · Cited by 669 · see citing works
The socioecology of elephants: analysis of the processes creating multitiered social structures
Wittemyer, G., Douglas-Hamilton, I., & Getz, W. M. (2005) · Animal Behaviour · doi:10.1016/j.anbehav.2004.08.018 · Cited by 591 · see citing works
Self-citationIllegal killing for ivory drives global decline in African elephants
Wittemyer, G., Northrup, J. M., Blanc, J., Douglas‐Hamilton, I., Omondi, P., & Burnham, K. P. (2014) · Proceedings of the National Academy of Sciences · doi:10.1073/pnas.1403984111 · Cited by 427 · see citing works
Self-citationThe demography of an African elephant ( <i>Loxodonta africana</i> ) population in Amboseli, Kenya
Moss, C. J. (2001) · Journal of Zoology · doi:10.1017/s0952836901001212 · Cited by 374 · see citing works
Devastating Decline of Forest Elephants in Central Africa
Maisels, F. G., Strindberg, S., Blake, S., Wittemyer, G., Hart, J. A., Williamson, E. A., Aba’a, R., Abitsi, G., Ambahe, R., Amsini, F., et al. (2013) · PLoS ONE · doi:10.1371/journal.pone.0059469 · Cited by 353 · see citing works
Self-citationState and evolution of the African rainforests between 1990 and 2010
Mayaux, P., Pekel, J., Desclée, B., Donnay, F., Lupi, A., Achard, F., Clerici, M., Bodart, C., Brink, A. B., Nasi, R., et al. (2013) · Philosophical Transactions of the Royal Society B Biological Sciences · doi:10.1098/rstb.2012.0300 · Cited by 282 · see citing works
Hewison, A. J. M., Hewison, A. J. M., Gaillard, J., et al. (1999) · Trends in Ecology & Evolution · doi:10.1016/s0169-5347(99)01592-x · Cited by 281 · see citing works
Severe drought and calf survival in elephants
Foley, C., Pettorelli, N., & Foley, L. S. (2008) · Biology Letters · doi:10.1098/rsbl.2008.0370 · Cited by 227 · see citing works
Forest Elephant Crisis in the Congo Basin
Blake, S., Strindberg, S., Boudjan, P., Makombo, C., Inogwabini, B., Omari, I., Grossmann, F., Bene, L. B., de Semboli, B. B., Mbenzo-Abokome, V., et al. (2007) · PLoS Biology · doi:10.1371/journal.pbio.0050111 · Cited by 173 · see citing works
Forest Elephants: Tree Planters of the Congo
Blake, S., Deem, S. L., Mossimbo, E., Maisels, F. G., & Walsh, P. (2009) · Biotropica · doi:10.1111/j.1744-7429.2009.00512.x · Cited by 156 · see citing works
Gough, K. F., & Kerley, G. I. H. (2006) · Oryx · doi:10.1017/s0030605306001189 · Cited by 125 · see citing works
Breeding phenology in relation to NDVI variability in free-ranging African elephant
Wittemyer, G., Rasmussen, H. B., & Douglas‐Hamilton, I. (2007) · Ecography · doi:10.1111/j.0906-7590.2007.04900.x · Cited by 123 · see citing works
Self-citationWill Elephants Soon Disappear from West African Savannahs?
Bouché, P., Douglas‐Hamilton, I., Wittemyer, G., Nianogo, A. J., Doucet, J., Lejeune, P., & Vermeulen, C. (2011) · PLoS ONE · doi:10.1371/journal.pone.0020619 · Cited by 115 · see citing works
Self-citationComparative Demography of an At-Risk African Elephant Population
Wittemyer, G., Daballen, D., & Douglas‐Hamilton, I. (2013) · PLoS ONE · doi:10.1371/journal.pone.0053726 · Cited by 115 · see citing works
Self-citationSeed dispersal strategies and the threat of defaunation in a Congo forest
Beaune, D., Bretagnolle, F., Bollache, L., Hohmann, G., Surbeck, M., & Fruth, B. (2012) · Biodiversity and Conservation · doi:10.1007/s10531-012-0416-x · Cited by 98 · see citing works
Ecology of forest elephant distribution and its implications for conservation
Blake, S. (2002) · ERA · Cited by 95 · see citing works
Foley, C., & Faust, L. J. (2010) · Oryx · doi:10.1017/s0030605309990706 · Cited by 91 · see citing works
Beyers, R. L., Hart, J. A., SINCLAIR, A. R. E., Grossmann, F., Klinkenberg, B., & Dino, S. (2011) · PLoS ONE · doi:10.1371/journal.pone.0027129 · Cited by 87 · see citing works
Demographic status of elephants in the Samburu and Buffalo Springs National Reserves, Kenya
Wittemyer, G., Daballen, D., Rasmussen, H. B., Kahindi, O., & Douglas‐Hamilton, I. (2005) · African Journal of Ecology · doi:10.1111/j.1365-2028.2004.00543.x · Cited by 67 · see citing works
Self-citationLong-Term Monitoring of Dzanga Bai Forest Elephants: Forest Clearing Use Patterns
Turkalo, A. K., Wrege, P. H., & Wittemyer, G. (2013) · PLoS ONE · doi:10.1371/journal.pone.0085154 · Cited by 65 · see citing works
Self-citationFruit, Minerals, and Forest Elephant Trails: Do All Roads Lead to Rome?
Blake, S., & Inkamba‐Nkulu, C. (2004) · Biotropica · doi:10.1111/j.1744-7429.2004.tb00332.x · Cited by 59 · see citing works
Reconciling Apparent Conflicts between Mitochondrial and Nuclear Phylogenies in African Elephants
Ishida, Y., Oleksyk, T. K., Georgiadis, N. J., et al. (2011) · PLoS ONE · doi:10.1371/journal.pone.0020642 · Cited by 57 · see citing works
Fruit, Minerals, and Forest Elephant Trails: Do All Roads Lead to Rome?1
Blake, S., & Inkamba‐Nkulu, C. (2004) · Biotropica · doi:10.1646/03215 · Cited by 52 · see citing works
Elephant Natural History: A Genomic Perspective
Roca, A. L., Ishida, Y., Brandt, A. L., Benjamin, N. R., Zhao, K., & Georgiadis, N. J. (2014) · Annual Review of Animal Biosciences · doi:10.1146/annurev-animal-022114-110838 · Cited by 51 · see citing works
Slow intrinsic growth rate in forest elephants indicates recovery from poaching will require decades
Turkalo, A. K., Wrege, P. H., & Wittemyer, G. (2016) · Journal of Applied Ecology · doi:10.1111/1365-2664.12764 · Cited by 48 · see citing works
Self-citationOpening a larger window onto forest elephant ecology
Wrege, P. H., Rowland, E. D., Bout, N., & Doukaga, M. (2011) · African Journal of Ecology · doi:10.1111/j.1365-2028.2011.01310.x · Cited by 26 · see citing works
Self-citation12. Female Reproductive Strategies: Individual Life Histories
Moss, C. J., & Lee, P. C. (2019) · doi:10.7208/9780226542263-014 · Cited by 14 · see citing works
Estimating forest elephant age
Turkalo, A. K. (2013) · African Journal of Ecology · doi:10.1111/aje.12087 · Cited by 13 · see citing works
Self-citationBrooks, M., Mugabo, M., Rodgers, G. M., et al. (2015) · Journal of Animal Ecology · doi:10.1111/1365-2656.12465 · Cited by 13 · see citing works
Flagged first, then by citations
Research works printed but not linked: 1
- [22]Douglas-Hamilton I. On the ecology and behaviour of the African elephant: Elephants of Lake Manyara [D.Phil.]. Oxford: Oxford University; 1972.
Cited by
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Aging: What We Can Learn From Elephants
Chusyd, D. E., Ackermans, N. L., Austad, S. N., Hof, P. R., Mielke, M. M., Sherwood, C. C., & Allison, D. B. (2021) · Frontiers in Aging · doi:10.3389/fragi.2021.726714 · Cited by 23 · see citing works
Hope, S. F., Willgohs, K. R., Dittakul, S., & Plotnik, J. M. (2025) · Learning & Behavior · doi:10.3758/s13420-024-00655-y · Cited by 8 · see citing works
- Authors
- Turkalo, A. K., Wrege, P. H., & Wittemyer, G.
- Affiliations
- Cornell University (US)
- Save the Elephants (KE)
- Corresponding author
- Wittemyer, George
- Venue
- PLOS ONE
- Publisher
- Public Library of Science (PLoS)
- Published
- 2018-02-15
- Volume
- 13
- Issue
- 2
- Pages
- e0192777
- ISSN
- 1932-6203 (ISSN-L)
- PMC
- PMC5813957
- OpenAlex
- W2790990223
- Cited by
- 42
- References
- 39
- Citations by year
- 2026: 4 · 2025: 5 · 2024: 4 · 2023: 3 · 2022: 8 · 2021: 7 · 2020: 4 · 2019: 7
- FWCI
- 3.38
- Type
- journal article
- Language
- en
- Open access
- gold
- doi.org
- Licence
- Locations
- PLoS ONE (publishedVersion, cc-by)
- PubMed Central (publishedVersion, cc-by)
- PubMed (publishedVersion)
- DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion, cc-by-sa)
- Figshare (submittedVersion, cc-by)
- Greater South Information System
- Funders
- U.S. Fish and Wildlife Service
- Topics
- Physical Sciences › Environmental Science › Ecology › Wildlife Ecology and Conservation
- Social Sciences › Psychology › Social Psychology › Primate Behavior and Ecology
- Physical Sciences › Environmental Science › Ecology › Marine animal studies overview
- Keywords
- African forest elephant, Loxodonta africana, demography, survivorship, fecundity, generation time, sex ratio, calf mortality, ivory poaching, population growth
- MeSH terms
- Age Factors, Animals, Central African Republic, Elephants, Female, Male, Population Dynamics, Sex Ratio, Forests
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