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Beetle rhythms in the rain: time series analysis and seasonal activity patterns of sympatric large-sized Goliathinae in Uganda’s forests
Published online by Cambridge University Press: 06 November 2025
Abstract
In tropical forests, the relative thermal and climatic stability contrasts with the seasonal oscillations, mainly due to rainfall patterns, that structure life cycles in temperate zones, leading to different ecological strategies among species. This study investigates the seasonal activity patterns and size-abundance relationships of four sympatric Goliath beetle species (Goliathus goliatus, Mecynorhina confluens, Mecynorrhinella poggei, and Fornasinius russus) in the Mabira Forest Reserve and in other forest areas, Uganda. Over three years (2021–2023), 1,231 individuals were sampled monthly using standardised traps and random transects. Time series analyses were used to explore patterns of abundance. We found a significant negative correlation between body size and abundance (r = –0.78, P < 0.05), with the smaller species, M. confluens and F. russus, being most numerous. Time series and Analysis of Variance (ANOVA) revealed significant sinusoidal patterns of seasonality for G. goliatus, M. poggei, and F. russus, while M. confluens showed non-significant cyclical trends, indicating potential stochastic fluctuations or greater ecological flexibility. Seasonal peaks were species-specific and generally occurred during transitional periods between wet and dry seasons, diverging from previously reported insect patterns peaking during the wet season. These findings suggest that differing phenological strategies may facilitate coexistence and niche partitioning, particularly among species differing in body size. Furthermore, larger species appeared to emerge earlier in the year, possibly reflecting life history adaptations or competitive dynamics. Our study highlights the importance of long-term, species-specific monitoring to understand ecological roles and vulnerabilities of tropical beetles, especially large-bodied taxa increasingly threatened by habitat loss and climate variability. Such insights are essential for informing conservation strategies in biodiverse tropical ecosystems.
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References
Abele, LG (1976) Comparative species richness in fluctuating and constant environments: coral-associated decapod Crustaceans. Science 192, 461–463.10.1126/science.192.4238.461CrossRefGoogle ScholarPubMed
Ajong, SN, Luiselli, L, Lado, TF, Demaya, GS, Eniang, EA, Segniagbeto, GH, Ketoh, GK, Le Duc, O, De Palma, M, Amori, G, Fa, JE, Behangana, M, Hema, EM, and Dendi, D (2024) Living with hyraxes: biogeography and comparative ecology of West African Fornasinius beetles. African Journal of Ecology 62(3), e13325.10.1111/aje.13325CrossRefGoogle Scholar
Alexander, JM and Levine, JM (2019). Earlier phenology of a nonnative plant increases impacts on native competitors. Proceedings of the National Academy of Sciences of the United States of America 201820569.10.1073/pnas.1820569116CrossRefGoogle Scholar
Allemand, R, Aberlenc, HP (1991) Une méthode efficace d’échantillonnage de l’entomofaune des frondaisons: le piège attractif aérien. Bulletin de la Société Entomologique Suisse 64, 293–305.Google Scholar
Berkov, A (2018) Seasonality and stratification: neotropical saproxylic beetles respond to a heat and moisture continuum with conservatism and plasticity. Saproxylic Insects: Diversity, Ecology and Conservation 547–578.10.1007/978-3-319-75937-1_16CrossRefGoogle Scholar
Blackburn, T M and Lawton, J H (1994) Population abundance and body size in animal assemblages. Philosophical Transactions of the Royal Society of London B. 343, 33–39.Google Scholar
Blackburn, T M and Gaston, K J (1997) A critical assessment of the form of the interspecific relationship between abundance and body size in animals. Journal of Animal Ecology 66, 233–249.10.2307/6025CrossRefGoogle Scholar
Bouchard, P, Smith, A B, Douglas, H, Gimmel, M L, Brunke, A J and Kanda, K (2017) Biodiversity of coleoptera. Insect Biodiversity: Science and Society, Volume I, Second Edition. Edited by Robert, G. Foottit and Peter, H. Adler, pp. 337–417
10.1002/9781118945568.ch11CrossRefGoogle Scholar
Brin, A, Bouget, C, Brustel, H and Jactel, H (2011). Diameter of downed woody debris does matter for saproxylic beetle assemblages in temperate oak and pine forests. Journal of Insect Conservation 15, 653–669.10.1007/s10841-010-9364-5CrossRefGoogle Scholar
Brown, J H, Gillooly, J F, Allen, A P, Savage, VM, and West, G B (2004) Toward a metabolic theory of ecology. Ecology 85, 1771–1789.10.1890/03-9000CrossRefGoogle Scholar
Brown, J H, and Maurer, B A (1987) Evolution of species assemblages— Effects of energetic constraints and species dynamics on the diversi- fication of the North American avifauna. The American Naturalist 130, 1–17.10.1086/284694CrossRefGoogle Scholar
Christiansen, P (2013) Larval growth rates and sexual differences of resource allocation in the cetoniine scarab Mecynorhina polyphemus Fabricius 1781 (Coleoptera: Scarabaeidae: Goliathini). Journal of Natural History, 47(19-20), 1287–1307.10.1080/00222933.2012.763061CrossRefGoogle Scholar
Cleland, EE, Esch, E and McKinney, J (2015) Priority effects vary with species identity and origin in an experiment varying the timing of seed arrival. Oikos 124, 33–40.10.1111/oik.01433CrossRefGoogle Scholar
Degut, A, Fischer, K, Quque, M, Criscuolo, F, Michalik, P, and Beaulieu, M (2022) Irreversible impact of early thermal conditions: an integrative study of developmental plasticity linked to mobility in a butterfly species. Journal of Experimental Biology 225, jeb243724.10.1242/jeb.243724CrossRefGoogle Scholar
Denlinger, D L (1980) Seasonal and annual variation in insect abundance in the Nairobi National Park, Kenya. Biotropica 12, 100–106.10.2307/2387725CrossRefGoogle Scholar
Denlinger, DL (1986) Dormancy in tropical insects. Annu Rev Entomol 31, 239–264
10.1146/annurev.en.31.010186.001323CrossRefGoogle ScholarPubMed
De Palma, M, Takano, H, Léonard, P and Bouyer, T (2020) Barcoding analysis and taxonomic revision of Goliathus Lamarck, 1802 (Scarabaeidae, Cetoniinae). Entomologica Africana 25, 11–32.Google Scholar
De Palma, M, Takano, H, Léonard, P and Bouyer, T (2024) Taxonomic revision of Mecynorhina Hope, 1837 and allied African genera with simple or bifurcate horns (Coleoptera, Scarabaeidae, Cetoniinae, Goliathini). Entomologica Africana 29, 11–32.Google Scholar
De Vega, C, Arista, M, Ortiz, P L, Herrera, CM and Talavera, S (2011). Endozoochory by beetles: a novel seed dispersal mechanism. Annals of Botany 107(4), 629–637.10.1093/aob/mcr013CrossRefGoogle ScholarPubMed
Devries, PJ and Walla, T R (2001) Species diversity and community structure in Neotropical fruit-feeding butterflies. Biological Journal of the Linnean Society 74, 1–15.10.1111/j.1095-8312.2001.tb01372.xCrossRefGoogle Scholar
Diez, JM, Ibáñez, I, Miller-Rushing, AJ, Mazer, SJ, Crimmins, TM, Crimmins, MA et al. (2012) Forecasting phenology: from species variability to community patterns. Ecology Letters 15, 545–553.10.1111/j.1461-0248.2012.01765.xCrossRefGoogle ScholarPubMed
Dunbar, RIM, Korstjens, AH and Lehmann, J (2009) Time as an ecological constraint. Biological Reviews 84, 413–429.10.1111/j.1469-185X.2009.00080.xCrossRefGoogle Scholar
Finn, J A, and Gittings, T (2003) A review of competition in north temperate dung beetle communities. Ecological Entomology 28(1), 1–13.10.1046/j.1365-2311.2002.00487.xCrossRefGoogle Scholar
Foit, J (2010). Distribution of early-arriving saproxylic beetles on standing dead Scots pine trees. Agricultural and Forest Entomology 12, 133–141.10.1111/j.1461-9563.2009.00461.xCrossRefGoogle Scholar
Fountain-Jones, N M, Baker, S C, and Jordan, G J (2015). Moving beyond the guild concept: developing a practical functional trait framework for terrestrial beetles. Ecological Entomology 40, 1–13.10.1111/een.12158CrossRefGoogle Scholar
Fungo, B, Eilu, G, Tweheyo, M and Baranga, D (2013) Forest disturbance and cropping mixtures influence crop raiding by red-tailed monkey and grey-cheeked mangabey around Mabira Forest Reserve, Uganda. Journal of Ecology and The Natural Environment 5(2), 14–23.10.5897/JENE11.028CrossRefGoogle Scholar
Frith, C and Frith, D (1985). Seasonality of insect abundance in an Australian upland tropical rainforest. Australian Journal of Ecology 10, 237–248.10.1111/j.1442-9993.1985.tb00886.xCrossRefGoogle Scholar
Gaston, K J and Lawton, J H (1988) Patterns in body size, population- dynamics, and regional distribution of bracken herbivores. The American Naturalist 132, 662–680.10.1086/284881CrossRefGoogle Scholar
Gillespie, M A, Birkemoe, T and Sverdrup-Thygeson, A (2017). Interactions between body size, abundance, seasonality, and phenology in forest beetles. Ecology and Evolution 7(4), 1091–1100.10.1002/ece3.2732CrossRefGoogle ScholarPubMed
Godoy, O and Levine, JM (2014). Phenology effects on invasion success: insights from coupling field experiments to coexistence theory. Ecology 95, 726–736.10.1890/13-1157.1CrossRefGoogle ScholarPubMed
Gossner, MM, Lachat, T, Brunet, J, Isacsson, G, Bouget, C, Brustel, H, Brandl, R, Weisser, WW and Mueller, J (2013) Current near-to-nature forest management effects on functional trait composition of saproxylic beetles in beech forests. Conservation Biology 27, 605–614.10.1111/cobi.12023CrossRefGoogle ScholarPubMed
Grimbacher, P S and Stork, N E (2009) Seasonality of a diverse beetle assemblage inhabiting lowland tropical rain forest in Australia. Biotropica 41(3), 328–337.10.1111/j.1744-7429.2008.00477.xCrossRefGoogle Scholar
Grove, S J (2002). Saproxylic insect ecology and the sustainable management of forests. Annual Review of Ecology and Systematics 33, 1–23.10.1146/annurev.ecolsys.33.010802.150507CrossRefGoogle Scholar
Hanski, I (1987). Carrion fly community dynamics: patchiness, seasonality and coexistence. Ecological Entomology 12(3), 257–266.10.1111/j.1365-2311.1987.tb01004.xCrossRefGoogle Scholar
Horgan, F G (2005) Effects of deforestation on diversity, biomass and function of dung beetles on the eastern slopes of the Peruvian Andes. Forest Ecology and Management 216(1-3), 117–133.10.1016/j.foreco.2005.05.049CrossRefGoogle Scholar
Janzen, D H (1973). Sweep samples of tropical foliage insects: effects of seasons, vegetation types, elevation, time of day, and insularity. Ecology 54, 687–708.10.2307/1935359CrossRefGoogle Scholar
Jonsell, M, Weslien, J and Ehnstrom, B (1998). Substrate requirements of red-listed saproxylic invertebrates in Sweden. Biodiversity and Conservation 7, 749–764.10.1023/A:1008888319031CrossRefGoogle Scholar
Kaspari, M and Weiser, MD (2000) Ant activity along moisture gradients in a Neotropical forest. Biotropica 32, 703–711.10.1111/j.1744-7429.2000.tb00518.xCrossRefGoogle Scholar
Kharouba, HM, Ehrlén, J, Gelman, A, Bolmgren, K, Allen, JM, Travers, S.E. and Wolkovich, EM (2018). Global shifts in the phenological synchrony of species interactions over recent decades. Proceedings of the National Academy of Sciences of the United States of America 115, 5211–5216.10.1073/pnas.1714511115CrossRefGoogle ScholarPubMed
Kishimoto-Yamata, K and Itioka, T (2015) How much have we learned about seasonality in tropical insect abundance since Wolda (1988)? Entomological Science 18, 407–419
10.1111/ens.12134CrossRefGoogle Scholar
Kotiaho, JS, Kaitala, V, Komonen, A, and Paivinen, J (2005). Predicting the risk of extinction from shared ecological characteristics. Proceedings of the National Academy of Sciences of the United States of America 102, 1963–1967.10.1073/pnas.0406718102CrossRefGoogle ScholarPubMed
Lee, C, Baxt, A, Castillo, S, Berkov, A (2014) Stratification in French Guiana: Cerambycid beetle go up when rains come down. Biotropica 46, 302–311
10.1111/btp.12101CrossRefGoogle Scholar
Leigh, E G J (2004) How wet are the wet tropics. In Losos, EC and Leigh, EGJ (Eds.). Tropical forest diversity and dynamism. The University of Chicago Press, Chicago, Illinois.Google Scholar
Lissauer, J J, Barnes, J W and Chambers, J E (2012) Obliquity variations of a moonless Earth. Icarus 217(1), 77–87.10.1016/j.icarus.2011.10.013CrossRefGoogle Scholar
Luiselli, L, Fa, JE, Le Duc, O, Eniang, EA, Gonedele-Bi, S, Segniagbeto, GH, … and Dendi, D (2025). Red listing African Goliath Beetles: assessing threats and conservation needs. African Journal of Ecology, 63, e70018.10.1111/aje.70018CrossRefGoogle Scholar
Mallon, DP, Hoffmann, M, Grainger, MJ, Hibert, F, van Vliet, H and McGowan, PJK (2015) An IUCN situation analysis of West and Central Africa. Occasional Paper of the IUCN Species Survival Commission 54, 40. IUCN, Gland.Google Scholar
Maquart, PO, and Malec, P (2017) On the distribution and natural history of a rarely encountered species: Goliathus (Fornasinius) klingbeili Zöller, Fiebig, & Schulze, 1995 (Coleoptera: Scarabaeidae: Cetoniinae). Zootaxa 4341, 441–444.10.11646/zootaxa.4341.3.12CrossRefGoogle ScholarPubMed
Muafor, FJ, and LeGall, P (2011) Beetle trade in SouthWest Cameroon. IRD, Yaoundé. Available online:https://horizon.documentation.ird.fr/exl-doc/pleins_textes/divers1311/010057004.pdf (accessed on 02 May 2025).Google Scholar
Muinde, J and Katumo, D M (2024) Beyond bees and butterflies: the role of beetles in pollination system. Journal for Nature Conservation 77, 126523.10.1016/j.jnc.2023.126523CrossRefGoogle Scholar
Murillo-Rincón, AP, Kolter, NA, Laurila, A and Orizaola, G (2017) Intraspecific priority effects modify compensatory responses to changes in hatching phenology in an amphibian. J. Anim. Ecol. 86, 128–135.10.1111/1365-2656.12605CrossRefGoogle Scholar
Nakazawa, T and Doi, H (2012). A perspective on match/mismatch of phenology in community contexts. Oikos 121, 489–495.10.1111/j.1600-0706.2011.20171.xCrossRefGoogle Scholar
Nee, S, Read, AF, Greenwood, JJ, and Harvey, PH (1991) The relationship between abundance and body size in British birds. Nature 351(6324), 312–313.10.1038/351312a0CrossRefGoogle Scholar
Nichols, E, Spector, S, Louzada, J, Larsen, T, Amezquita, S, Favila, M E and Network, T S R (2008) Ecological functions and ecosystem services provided by Scarabaeinae dung beetles. Biological Conservation 141, 1461–1474.10.1016/j.biocon.2008.04.011CrossRefGoogle Scholar
Nieminen, M (2015) Distance decay is uncommon in large-scale population synchrony of common moths: Does it promote vulnerability to climate change? Insect Conservation and Diversity 8, 438–447.10.1111/icad.12121CrossRefGoogle Scholar
Novotny, V and Basset, Y (2005) Host specificity of insect herbivores in tropical forests. Proceedings of the Royal Society B: Biological Sciences 272, 1083–1090.10.1098/rspb.2004.3023CrossRefGoogle ScholarPubMed
Owen, D F and Chanter, D O (1970) Species diversity and seasonal abundance in tropical Ichneumonidae. Oikos 21, 142–144.10.2307/3543849CrossRefGoogle Scholar
Pedley, S M and Dolman, P M (2014) Multi-taxa trait and functional responses to physical disturbance. Journal of Animal Ecology 83, 1542–1552.10.1111/1365-2656.12249CrossRefGoogle ScholarPubMed
Peters, R H (1983). The Ecological Implications of Body Size. Cambridge, UK: Cambridge University Press.10.1017/CBO9780511608551CrossRefGoogle Scholar
Poulin, R (1999) Body size vs abundance among parasite species: positive relationships?. Ecography 22(3), 246–250.10.1111/j.1600-0587.1999.tb00499.xCrossRefGoogle Scholar
Poorter, LVDS, Masha, T, Arets, EJMM, Ascarrunz, N, Enquist, B, Finegan, B. et al. (2017) Biodiversity and climate determine the functioning of Neotropical forests. Global Ecology and Biogeography 26(12), 1423–1434.10.1111/geb.12668CrossRefGoogle Scholar
Pozsgai, G and Littlewood, N A (2014) Ground beetle (Coleoptera: Carabidae) population declines and phenological changes: Is there a connection? Ecological Indicators 41, 15–24.10.1016/j.ecolind.2014.01.029CrossRefGoogle Scholar
Prather, CM, Pelini, SL, Laws, A, Rivest, E, Woltz, M, Bloch, C P and Joern, A (2013) Invertebrates, ecosystem services and climate change. Biological Reviews 88(2), 327–348
10.1111/brv.12002CrossRefGoogle ScholarPubMed
Rasmussen, NL, Van Allen, BG and Rudolf, VHW (2014) Linking phenological shifts to species interactions through size-mediated priority effects. Journal of Animal Ecology 83, 1206–1215.10.1111/1365-2656.12203CrossRefGoogle ScholarPubMed
Ratcliffe, BC (2003) The dynastine scarab beetles of Costa Rica and Panama (Coleoptera: Scarabaeidae: Dynastinae). Bulletin of the University of Nebraska State Museum 16, 1–506.Google Scholar
R Core Team (2013). A Language and Environment for Statistical Computing. Available at: https://www.r-project.org/.Google Scholar
Raw, F (1951) The ecology of the garden chafer, Phyllopertha horticola (L.) with preliminary observations on control measures. Bulletin of Entomological Research 42, 605–646.10.1017/S0007485300029023CrossRefGoogle Scholar
Rehm, EM, Feeley, KJ (2015) Freezing temperatures as a limit to forest recruitment above tropical Andean treelines. Ecology 96, 1856–1865
10.1890/14-1992.1CrossRefGoogle ScholarPubMed
Richards, LA and Windsor, DM (2007) Seasonal variation of arthropod abundance in gaps and the understorey of a lowland moist forest in Panama. Journal of Tropical Ecology 23, 169–176.10.1017/S0266467406003907CrossRefGoogle Scholar
Rudolf, VHW (2018) Nonlinear effects of phenological shifts link interannual variation to species interactions. Journal of Animal Ecology 87, 1395–1406.10.1111/1365-2656.12850CrossRefGoogle ScholarPubMed
Shah, NA and Shah, N (2022) Ecological benefits of scarab beetles (Coleoptera: Scarabaeidae) on nutrient cycles: a review article. Advances in Biochemistry and Biotechnology 7(1), 16.Google Scholar
Siemann, E, Tilman, D and Haarstad, J (1996) Insect species diversity, abundance and body size relationships. Nature 380, 704–706.10.1038/380704a0CrossRefGoogle Scholar
Siemann, E, Tilman, D and Haarstad, J (1999) Abundance, diversity and body size: Patterns from a grassland arthropod community. Journal of Animal Ecology 68, 824–835.10.1046/j.1365-2656.1999.00326.xCrossRefGoogle Scholar
Slade, EM, Mann, DJ and Lewis, OT (2011) Biodiversity and ecosystem function of tropical forest dung beetles under contrasting logging regimes. Biological Conservation 144, 166–174.10.1016/j.biocon.2010.08.011CrossRefGoogle Scholar
Smythe, N (1982). The seasonal abundance of night-flying insects in a Neotropical forest. In Leigh, EG, Rand, AS and Windsor, DM (Eds.), The ecology of a tropical forest: Seasonal rhythms and long term changes. Washington DC; Smithonian Institution Press.Google Scholar
Sombroek, W (2001) Spatial and temporal patterns of Amazon rainfall. Ambio 30, 388–396
10.1579/0044-7447-30.7.388CrossRefGoogle ScholarPubMed
Stenseth, NC, Ottersen, G, Hurrell, JW, Mysterud, A, Lima, M, Chan, KS, Yocooz, NG and Ådlandsvik, B (2003) Studying climate effects on ecology through the use of climate indices: the North Atlantic Oscillation, El Nino Southern Oscillation and beyond. Proceedings of the Royal Society of London. Series B: Biological Sciences 270(1529), 2087–2096.10.1098/rspb.2003.2415CrossRefGoogle ScholarPubMed
Stier, AC, Geange, SW, Hanson, KM and Bolker, BM (2013) Predator density and timing of arrival affect reef fish community assembly. Ecology 94, 1057–1068.10.1890/11-1983.1CrossRefGoogle ScholarPubMed
Tind Nielsen, S (2007) Deforestation and biodiversity: effects of bushland cultivation on dung beetles in semi-arid Tanzania. Biodiversity and Conservation 16, 2753–2769.10.1007/s10531-007-9213-3CrossRefGoogle Scholar
Touroult, J, Le Gall, P (2001) Les Cétoines du Sud-Bénin (Coleoptera, Cetoniidae). Etude comparative du peuplement de différents biotopes. Cetoniimania 1, 29–39.Google Scholar
Touroult, J and Le Gall, P (2013) Fruit feeding Cetoniinae community structure in an anthropogenic landscape in West Africa. Journal of Insect Conservation 17, 23–34.10.1007/s10841-012-9483-2CrossRefGoogle Scholar
Van Schaik, CP and Pfannes, KR (2005) Tropical climates and phenology: a primate perspective. Cambridge Studies in Biological and Evolutionary Anthropology 44, 23.Google Scholar
Vulinec, K (2000). Dung beetles (Coleoptera: Scarabaeidae), monkeys, and conservation in Amazonia. Florida Entomologist 229–241.10.2307/3496341CrossRefGoogle Scholar
Weldemariam, EC, Jakisa, ES and Ahebwe, DA (2017) Implication of forest zonation on tree species composition, diversity and structure in Mabira Forest, Uganda. Environment, Earth and Ecology 1, 1
10.24051/eee/69224CrossRefGoogle Scholar
White, EP, Ernest, SM, Kerkhoff, AJ and Enquist, BJ (2007) Relationships between body size and abundance in ecology. Trends in Ecology & Evolution 22(6), 323–330.10.1016/j.tree.2007.03.007CrossRefGoogle ScholarPubMed
Wolda, H (1978) Seasonal fluctuations in rainfall, food and abundance of tropical insects. Journal of Animal Ecology 47, 369–381.10.2307/3789CrossRefGoogle Scholar
Wolda, H (1988) Insect seasonality: why? Annual Review of Ecology, Evolution, and Systematics 19,1–19
10.1146/annurev.es.19.110188.000245CrossRefGoogle Scholar
Wolkovich, EM, Cook, BI, McLauchlan, KK and Davies, TJ (2014) Temporal ecology in the Anthropocene. Ecology Letters 17, 1365–1379
10.1111/ele.12353CrossRefGoogle ScholarPubMed
Woodward, G, Ebenman, B, Emmerson, M, Montoya, JM, Olesen, JM, Valido, A, and Warren, PH (2005) Body size in ecological networks. Trends in Ecology & Evolution 20, 402
10.1016/j.tree.2005.04.005CrossRefGoogle ScholarPubMed
Wright, JS (2002) Plant diversity in tropical forests: a review of mechanisms of species coexistence. Oecologia 130, 1–14.10.1007/s004420100809CrossRefGoogle ScholarPubMed
Yang, LH and Rudolf, VHW (2010) Phenology, ontogeny, and the effects of climate change on the timing of species interactions. Ecology Letters 13, 1–10.10.1111/j.1461-0248.2009.01402.xCrossRefGoogle ScholarPubMed
Young, T, Zefferman, E, Vaughn, K and Fick, S (2015) Initial success of native grasses is contingent on multiple interactions among exotic grass competition, temporal priority, rainfall, and site effects. AoB PLANTS 7, 081.10.1093/aobpla/plu081CrossRefGoogle Scholar