Abstract
Chimpanzees (Pan troglodytes) live in fission–fusion societies where community members form temporary parties that frequently change in size and composition. Chimpanzee party size and composition have been widely studied to identify proximate causes of grouping patterns, and party size estimates are used to assess population sizes and densities. Numerous socio-ecological factors influence chimpanzee party size, but findings differ across studies. Various methods to measure party size exist, including direct observations, motion-triggered camera (MTC) observations, and nest counts. However, comparative analyses of these methods are lacking. Here, we assess relative differences in four commonly used party size methods and we examine socio-ecological factors influencing party size of unhabituated chimpanzees (P. t. verus) at Seringbara, Nimba, Guinea. We also assess which method(s) best reflect the influence of socio-ecological factors on party size. Using data collected over 69 months, we show that night nest counts resulted in relatively larger party size estimates than the other methods, and day nest counts resulted in relatively smaller party size estimates. Direct and MTC observations did not differ in relative estimates of party size and composition. Both fruit abundance and presence of estrous females positively influenced party size, but this effect was only evident when measuring party size with MTCs. Methods thus differ in relative party size estimates and their ability to assess the impact of socio-ecological factors. We conclude that MTC observations best represent party size and the effect of socio-ecological factors at Nimba. MTCs show promising potential for studying grouping patterns in unhabituated chimpanzees.
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References
Anderson DP, Nordheim EV, Boesch C, Moermond T (2002) Factors influencing fission-fusion grouping in chimpanzees in the Taï National Park, Cote d'Ivoire. In: Boesch C, Hohmann G, Marchant L (eds) Behavioural diversity in chimpanzees and bonobos, 1st edn. Cambridge University Press, Cambridge, pp 90–101
Basabose AK (2004) Fruit availability and chimpanzee party size at Kahuzi montane forest, Democratic Republic of Congo. Primates 45:211–219. https://doi.org/10.1007/s10329-004-0087-7
Bertolani P, Boesch C (2008) Habituation of wild chimpanzees (Pan troglodytes) of the South group at Tai forest, Cote d'Ivoire: empirical measure of progress. Folia Primatol 79:162–171. https://doi.org/10.1159/000111720
Boesch C (1991) The effects of leopard predation on grouping patterns in forest chimpanzees. Behaviour 177:220–242. https://doi.org/10.1163/156853991X00544
Boesch C (1996) Social grouping in Taï chimpanzees. In: McGrew WC, Marchant LF, Nishida T (eds) Great ape societies, 1st edn. Cambridge University Press, Cambridge, pp 101–113
Boesch C, Kalan AK, Agbor A, Arandjelovic M, Dieguez P, Lapeyre V, Kühl HS (2016) Chimpanzees routinely fish for algae with tools during the dry season in Bakoun Guinea. Am J Primatol 79:e22613. https://doi.org/10.1002/ajp.22613
Boyer-Ontl KM, Pruetz JD (2014) Giving the forest eyes: The benefits of using camera traps to study unhabituated chimpanzees (Pan troglodytes verus) in Southeastern Senegal. Int J Primatol 35:881–894. https://doi.org/10.1007/s10764-014-9783-3
Brownlow AR, Plumptre AJ, Reynolds V, Ward R (2001) Sources of variation in the nesting behavior of chimpanzees (Pan troglodytes schweinfurthii) in the Budongo Forest, Uganda. Am J Primatol 55:49–55. https://doi.org/10.1002/ajp.1038
Chapman CA, Wrangham RW, Chapman LJ (1995) Ecological constraints on group-size—an analysis of spider monkey and chimpanzee subgroups. Behav Ecol Sociobiol 36:59–70. https://doi.org/10.1007/BF00175729
Després-Einspenner ML, Howe EJ, Drapeau P, Kühl HS (2017) An empirical evaluation of camera trapping and spatially explicit capture–recapture models for estimating chimpanzee density. Am J Primatol. https://doi.org/10.1002/ajp.22647
Doran D (1997) Influence of seasonality on activity patterns, feeding behavior, ranging, and grouping patterns in Tai chimpanzees. Int J Primatol 18:183–206. https://doi.org/10.1023/A:1026368518431
Field A (2009) Discovering statistics using SPSS, 3rd edn. SAGE Publications, London
Furuichi T, Hashimoto C, Tashiro Y (2001a) Extended application of a marked-nest census method to examine seasonal changes in habitat use by chimpanzees. Int J Primatol 22:913–928. https://doi.org/10.1023/A:1012057403512
Furuichi T, Hashimoto C, Tashiro Y (2001b) Fruit availability and habitat use by chimpanzees in the Kalinzu Forest, Uganda: examination of fallback foods. Int J Primatol 22:929–945. https://doi.org/10.1023/A:1012009520350
Goodall JM (1962) Nest building behavior in the free ranging chimpanzee. Ann N Y Acad Sci 102:455–467. https://doi.org/10.1111/j.1749-6632.1962.tb13652.x
Hashimoto C, Furuichi T, Tashiro Y (2001) What factors affect the size of chimpanzee parties in the Kalinzu Forest, Uganda? Examination of fruit abundance and number of estrous females. Int J Primatol 22:947–959. https://doi.org/10.1023/A:1012061504420
Hockings KJ, Anderson JR, Matsuzawa T (2010) Flexible feeding on cultivated underground storage organs by rainforest-dwelling chimpanzees at Bossou, West Africa. J Hum Evol 58:227–233. https://doi.org/10.1016/j.jhevol.2009.11.004
Humle T, Matsuzawa T (2001) Behavioural diversity among the wild chimpanzee populations of Bossou and neighbouring areas, Guinea and Cote d'Ivoire, West Africa. Folia Primatol 72:57–68. https://doi.org/10.1159/000049924
Itoh N, Nishida T (2007) Chimpanzee grouping patterns and food availability in Mahale Mountains National Park, Tanzania. Primates 48:87–96. https://doi.org/10.1007/s10329-006-0031-0
Koops K (2011) Elementary technology of foraging and shelter in the chimpanzees (Pan troglodytes verus) of the Nimba Mountains, Guinea. Dissertation, University of Cambridge
Koops K, Humle T, Sterck EHM, Matsuzawa T (2007) Ground-nesting by the chimpanzees of the Nimba Mountains, Guinea: environmentally or socially determined? Am J Primatol 69:407–419. https://doi.org/10.1002/ajp.20358
Koops K, McGrew WC, Matsuzawa T, Knapp LA (2012a) Terrestrial nest-building by wild chimpanzees (Pan troglodytes): implications for the tree-to-ground sleep transition in early hominins. Am J Phys Anthropol 148:351–361. https://doi.org/10.1002/ajpa.22056
Koops K, McGrew WC, de Vries J, Matsuzawa T (2012b) Nest-building by chimpanzees (Pan troglodytes verus) at Seringbara, Nimba Mountains: antipredation, thermoregulation, and antivector hypotheses. Int J Primatol 33:356–380. https://doi.org/10.1007/s10764-012-9585-4
Koops K, McGrew WC, Matsuzawa T (2013) Ecology of culture: do environmental factors influence foraging tool use in wild chimpanzees, Pan troglodytes verus? Anim Behav 85:175–185. https://doi.org/10.1016/j.anbehav.2012.10.022
Koops K, Wrangham R, Cumberlidge N, Fitzgerald MA, van Leeuwen KL, Rothman JM, Matsuzawa T (2019) Crab-fishing by chimpanzees in the Nimba Mountains, Guinea. J Hum Evol 133:230–241. https://doi.org/10.1016/j.jhevol.2019.05.002
Kühl HS, Kalan AK, Arandjelovic M, Aubert F, D’Auvergne L, Goedmakers A, Jones S, Kehoe L, Regnaut S, Tickle A, Ton E, van Schijndel J, Abwe EE, Angedakin S, Agbor A, Ayimisin EA, Bailey E, Bessone M, Bonnet M, Brazolla G, Buh VE, Chancellor R, Cipoletta C, Cohen H, Corogenes K, Coupland C, Curran B, Deschner T, Dierks K, Dieguez P, Dilambaka E, Diotoh O, Dowd D, Dunn A, Eshuis H, Fernandez R, Ginath Y, Hart J, Hedwig D, Ter Heegde M, Hicks TC, Imong I, Jeffery KJ, Junker J, Kadam P, Kambi M, Kienast I, Kujirakwinja D, Langergraber K, Lapeyre V, Lapuente J, Lee K, Leinert V, Meier A, Maretti G, Marrocoli S, Mbi TJ, Mihindou V, Moebius Y, Morgan D, Morgan B, Mulindahabi F, Murai M, Niyigabae P, Normand E, Ntare N, Ormsby LJ, Piel A, Pruetz J, Rundus A, Sanz C, Sommer V, Stewart F, Tagg N, Vanleeuwe H, Vergnes V, Willie J, Wittig RM, Zuberbuehler K, Boesch C (2016) Chimpanzee accumulative stone throwing. Sci Rep 6:22219. https://doi.org/10.1038/srep22219
Lehmann J, Boesch C (2004) To fission or to fusion: effects of community size on wild chimpanzee (Pan troglodytes verus) social organization. Behav Ecol Sociobiol 3:207–216. https://doi.org/10.1007/s00265-004-0781-x
Matsumoto-Oda A (1999) Mahale chimpanzees: grouping patterns and cycling females. Am J Primatol 47:197–207
Matsumoto-Oda A, Hosaka K, Huffman MA, Kawanaka K (1998) Factors affecting party size in chimpanzees of the Mahale mountains. Int J Primatol 19:999–1011. https://doi.org/10.1023/A:1020322203166
Matsuzawa T, Yamakoshi G (1996) Comparison of chimpanzee material culture between Bossou and Nimba, West Africa. In: Russon AE, Bard KA, Parker ST (eds) Reaching into thought: the minds of the great apes, 1st edn. Cambridge University Press, Cambridge, pp 211–232
Matsuzawa T, Humle T, Sugiyama Y (2011) The chimpanzees of Bossou and Nimba, 1st edn. Springer, Tokyo
McCarthy MS, Després-Einspenner ML, Samuni L, Mundry R, Lemoine S, Preis A, Wittig RM, Boesch C, Kühl HS (2018) An assessment of the efficacy of camera traps for studying demographic composition and variation in chimpanzees (Pan troglodytes). Am J Primatol. https://doi.org/10.1002/ajp.22904
Mitani JC (2006) Demographic influences on the behavior of chimpanzees. Primates 47:6–13. https://doi.org/10.1007/s10329-005-0139-7
Mitani JC, Watts DP, Lwanga JS (2002) Ecological and social correlates of chimpanzee party size and composition. In: Boesch C, Hohmann G, Marchant L (eds) Behavioural diversity in chimpanzees and bonobos, 1st edn. Cambridge University Press, Cambrigde, pp 102–111
Ndiaye PI, Lindshield SM, Badji L, Pacheco L, Wessling EG, Boyer KM, Pruetz JD (2018) Survey of chimpanzees (Pan troglodytes verus) outside protected areas in Southeastern Senegal. Afr J Wildl Res. https://doi.org/10.3957/056.048.013007
Newton-Fisher NE, Reynolds V, Plumptre AJ (2000) Food supply and chimpanzee (Pan troglodytes schweinfurthii) party size in the Budongo Forest Reserve, Uganda. Int J Primatol 21:613–628. https://doi.org/10.1023/A:1005561203763
Ogawa H, Idani G, Moore J, Pintea L, Hernandez-Aguilar A (2007) Sleeping parties and nest distribution of chimpanzees in the savanna woodland, Ugalla, Tanzania. Int J Primatol 28:1397–1412. https://doi.org/10.1007/s10764-007-9210-0
Plumptre AJ, Reynolds V (1997) Nesting behavior of chimpanzees: implications for censuses. Int J Primatol 18:475–485. https://doi.org/10.1023/A:1026302920674
Rovero F, Marshall AR (2009) Camera trapping photographic rate as an index of density in forest ungulates. J Appl Ecol 46:1011–1017. https://doi.org/10.1111/j.1365-2664.2009.01705.x
Rowcliffe JM, Field J, Turvey ST, Carbone C (2008) Estimating animal density using camera traps without the need for individual recognition. J Appl Ecol 45:1228–1236. https://doi.org/10.1111/j.1365-2664.2008.01473.x
Shimada MK (2000) A survey of the Nimba Mountains, West Africa, from three routes: confirmed new habitat and ant catching wand use of chimpanzees. Pan Afr News 7:7–10
Sommer V, Adanu J, Faucher I, Fowler A (2004) Nigerian chimpanzees (Pan troglodytes vellerosus) at Gashaka: two years of habituation efforts. Folia Primatol 75:295–316. https://doi.org/10.1159/000080208
Sugiyama Y (1999) Socioecological factors of male chimpanzee migration at Bossou, Guinea. Primates 40:61–68. https://doi.org/10.1007/BF02557702
Tagg N, McCarthy M, Dieguez P, Bocksberger G, Willie J, Mundry R, Stewart F, Arandjelovic M, Widness J, Landsmann A, Agbor A, Angedakin S, Ayimisin AE, Bessone M, Brazzola G, Corogenes K, ter Heegde M, Deschner T, Dilambaka E, Eno-Nku M, Eshuis H, Goedmakers A, Granjon AC, Head JS, Hermans V, Jones S, Kadam P, Kambi M, Langergraber K, Lapeyre V, Lapuente J, Lee K, Leinert V, Maretti G, Marrocoli S, Meier A, Nicholl S, Normand E, Ormsby LJ, Piel A, Robinson O, Sommer V, Tickle A, Ton E, van Schijndel J, Vanleeuwe H, Vergnes V, Wessling EG, Wittig RM, Zuberbuehler K, Kühl HS, Boesch C (2018) Nocturnal activity in wild chimpanzees (Pan troglodytes): evidence for flexible sleeping patterns and insights into human evolution. Am J Phys Anthropol 166:510–529. https://doi.org/10.1002/ajpa.23478
Takemoto H (2004) Seasonal change in terrestriality of chimpanzees in relation to microclimate in the tropical forest. Am J Phys Anthropol 124:81–92. https://doi.org/10.1002/ajpa.10342
Wakefield ML (2008) Grouping patterns and competition among female Pan troglodytes schweinfurthii at Ngogo, Kibale National Park, Uganda. Int J Primatol 29:907–929. https://doi.org/10.1007/s10764-008-9280-7
Wallis J (2002) Seasonal aspects of reproduction and sexual behavior in two chimpanzee populations: a comparison of Gombe (Tanzania) and Budongo (Uganda). In: Boesch C, Hohmann G, Marchant L (eds) Behavioural diversity in chimpanzees and bonobos. Cambridge University Press, Cambridge, pp 181–191
Widness J, Aronsen GP (2017) Camera trap data on mammal presence, behaviour and poaching: a case study from Mainaro, Kibale National Park, Uganda. Afr J Ecol 56:383–389. https://doi.org/10.1111/aje.12498
Wrangham RW, Chapman CA, Clark-Arcadi AP, Isabirye-Basuta G (1996) Social ecology of Kanyawara chimpanzees: implications for understanding the costs of great ape groups. In: McGrew WC, Marchant LF, Nishida T (eds) Great ape societies, 1st edn. Cambridge University Press, Cambridge, pp 45–57
Acknowledgements
We thank the Direction Generale de la Recherce Scientifque et l’Innovation Technologique (DGERSIT) and the Institut de Recherche Environnementale de Bossou (IREB) for research permission. For their help in the field, we thank Seringbara guides K. Doré, F. Doré, G. Zogbila, F. Zogbila, P. Cherif, H. Camara, N. Doré, D. Zogbila, Y. Zogbila, C. Samy and N. Gbouomy, and research assistants M. Reilly Plocek, M. Fitzgerald, P. Le Sommer, W. Edwards, J. Caraway, D. Montanari, N. James, I. Vélez del Burgo Guinea and D. Hassler. For statistical advice, we thank H. de Vries. We thank two anonymous reviewers for helpful and constructive comments on the manuscript. Research was supported by Grants from the Lucie Burgers Foundation for Comparative Behaviour Research (the Netherlands), Homerton College, Newnham College (Cambridge) and Claraz Stiftung to KK, and by MEXT-JSPS Grants #16H06283; LGP-U04, the Japan Society for the Promotion of Science (JSPS) Core-to-Core Program CCSN to TM.
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This research was non-invasive, complied with the laws of Guinea, and was approved by the Direction General de la Recherche Scientifique et l’Innovation Technologique (DGERSIT). Moreover, this research adhered to the guidelines as set down by the Division of Biological Anthropology, University of Cambridge, the host institute of the lead researcher (K. Koops) during the study.
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Supporting information on the frequency distribution of time intervals between subsequent party observations (Online Resource 1), as well as the linear relationships (Online Resource 2) and Spearman rank correlations (Online Resource 3) between chimpanzee party size, fruit abundance, fruit distribution and fruit availability are available online. (PDF 239 kb)
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van Leeuwen, K.L., Matsuzawa, T., Sterck, E.H.M. et al. How to measure chimpanzee party size? A methodological comparison. Primates 61, 201–212 (2020). https://doi.org/10.1007/s10329-019-00783-4
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DOI: https://doi.org/10.1007/s10329-019-00783-4