The Science of Nature

, 103:27 | Cite as

Ecological allometries and niche use dynamics across Komodo dragon ontogeny

  • Deni Purwandana
  • Achmad Ariefiandy
  • M. Jeri Imansyah
  • Aganto Seno
  • Claudio Ciofi
  • Mike Letnic
  • Tim S. JessopEmail author
Original Paper


Ontogenetic allometries in ecological habits and niche use are key responses by which individuals maximize lifetime fitness. Moreover, such allometries have significant implications for how individuals influence population and community dynamics. Here, we examined how body size variation in Komodo dragons (Varanus komodoensis) influenced ecological allometries in their: (1) prey size preference, (2) daily movement rates, (3) home range area, and (4) subsequent niche use across ontogeny. With increased body mass, Komodo dragons increased prey size with a dramatic switch from small (≤10 kg) to large prey (≥50 kg) in lizards heavier than 20 kg. Rates of foraging movement were described by a non-linear concave down response with lizard increasing hourly movement rates up until ∼20 kg body mass before decreasing daily movement suggesting reduced foraging effort in larger lizards. In contrast, home range area exhibited a sigmoid response with increased body mass. Intrapopulation ecological niche use and overlap were also strongly structured by body size. Thus, ontogenetic allometries suggest Komodo dragon’s transition from a highly active foraging mode exploiting small prey through to a less active sit and wait feeding strategy focused on killing large ungulates. Further, our results suggest that as body size increases across ontogeny, the Komodo dragon exhibited marked ontogenetic niche shifts that enabled it to function as an entire vertebrate predator guild by exploiting prey across multiple trophic levels.


Body size Predator Intrapopulation variation Resource use Individual ecological strategies 



We thank all the Komodo National Park staff and volunteers who assisted us in field work. Financial support from the Zoological Society of San Diego; the Komodo Species Survival Plan of the American Zoo and Aquarium Association, the Ocean Park Conservation Foundation, Hong Kong, the Mohamed bin Zayed species conservation fund and the Taronga Conservation Society, Australia is gratefully acknowledged. This research was conducted via a Memorandum of Understanding (MOU) between Komodo Survival Program and the Indonesian Department of Forestry and Conservation (PHKA).


  1. Ariefiandy A, Purwandana D, Coulson G, Forsyth DM, Jessop TS (2013) Monitoring the ungulate prey of the Komodo dragon Varanus komodoensis: distance sampling or faecal counts? Wildl Biol 19:126–137CrossRefGoogle Scholar
  2. Auffenberg W (1981) Behavioral ecology of the Komodo monitor. University Presses of Florida, GainesvilleGoogle Scholar
  3. Bolnick D, Ingram T (2010) Ecological release from interspecific competition leads to decoupled changes in population and individual niche width. Proc R Soc B 227:1789–1797CrossRefGoogle Scholar
  4. Bolnick DI, Svanbäck R, Fordyce JA et al (2003) The ecology of individuals: incidence and implications of individual specialization. Am Nat 161:1–28CrossRefPubMedGoogle Scholar
  5. Brown JS (1988) Patch use as an indicator of habitat preference, predation risk, and competition. Behav Ecol Sociobiol 22:37–47CrossRefGoogle Scholar
  6. Bull JJ, Jessop TS, Whitely M (2010) Deathly drool: evolutionary and ecological basis of septic bacteria in Komodo dragon mouths. PLoS ONE 5:e11097CrossRefPubMedPubMedCentralGoogle Scholar
  7. Carbone C, Mace GM, Roberts SC, Macdonald DW (1999) Energetic constraints on the diet of terrestrial carnivores. Nature 402:286–288CrossRefPubMedGoogle Scholar
  8. Carbone C, Cowlishaw G, Isaac NJ, Rowcliffe JM (2005) How far do animals go? Determinants of day range in mammals. Am Nat 165(2):290–297CrossRefPubMedGoogle Scholar
  9. Carbone C, Teacher A, Rowcliffe JM (2007) The costs of carnivory. PLoS Biol 5(2):e22. doi: 10.1371/journal.pbio.0050022 CrossRefPubMedPubMedCentralGoogle Scholar
  10. Ciofi C, Puswati J, Winana D et al (2007) Preliminary analysis of home range structure in the Komodo monitor, Varanus komodoensis. Copeia 2007:462–470CrossRefGoogle Scholar
  11. R Core Team (2013) R: A language and environment for statistical computing. R Foundation for Statistical Computing, Vienna, Austria. URL
  12. Damuth J (1981) Population density and body size in mammals. Nature 290(5808):699–700CrossRefGoogle Scholar
  13. Emlen JM (1966) The role of time and energy in food preferences. Am Nat 100:611–617CrossRefGoogle Scholar
  14. Fitzgerald M, Shine R, Lemckert F (2002) Spatial ecology of arboreal snakes (Hoplocephalus stephensii Elapidae) in an Eastern Australian forest. Aust Ecol 27:527–545CrossRefGoogle Scholar
  15. Frankham R (1998) Inbreeding and extinction: island populations. Conserv Biol 12:665–675CrossRefGoogle Scholar
  16. Garland T Jr (1983) Scaling the ecological cost of transport to body mass in terrestrial mammals. Am Nat 121:571–587CrossRefGoogle Scholar
  17. Giraldeau LA, Caraco T (2000) Social foraging theory. Princeton University Press, PrincetonGoogle Scholar
  18. Gompper ME, Gittleman JL (1991) Home range scaling: intraspecific and comparative trends. Oecologia 87:343–348CrossRefGoogle Scholar
  19. Green B, King D, Braysher M et al (1991) Thermoregulation, water turnover and energetics of free-living komodo dragons Varanus komodoensis. Comp Biochem Physiol A 99:97–101CrossRefGoogle Scholar
  20. Guarino F (2002) Spatial ecology of a large carnivorous lizard, Varanus varius (Squamata: Varaniae). J Zool (Lond) 258:449–457CrossRefGoogle Scholar
  21. Harris S, Cresswell WJ, Forde PG et al (1990) Home-range analysis using radio-tracking data: a review of problems and techniques particularly as applied to the study of mammals. Mammal Rev 20:97–123CrossRefGoogle Scholar
  22. Heithaus M, Dill L, Marshall G et al (2002) Habitat use and foraging behavior of tiger sharks (Galeocerdo cuvier) in a seagrass ecosystem. Mar Biol 140:237–248CrossRefGoogle Scholar
  23. Hooge PN, Eichenlaub W, Solomon E (1999) The Animal Movement Program. USGS, Alaska Biological Science Center. (Online)
  24. Huey RB, Pianka ER (1981) Ecological consequences of foraging mode. Ecology 62:991–999CrossRefGoogle Scholar
  25. Humphries NE, Weimerskirch H, Sims DW (2013) A new approach for objective identification of turns and steps in organism movement data relevant to random walk modelling. Methods Ecol Evol 4:930–938. doi: 10.1111/2041-210X.12096 Google Scholar
  26. Imansyah MJ, Jessop TS, Ciofi C, Akbar Z (2008) Ontogenetic differences in the spatial ecology of immature Komodo dragons. J Zool 274(2):107–115CrossRefGoogle Scholar
  27. Jessop TS et al (2004) Distribution, use and selection of nest type by Komodo Dragons. Biol Conserv 117:463–470CrossRefGoogle Scholar
  28. Jessop TS, Madsen T, Sumner J et al (2006) Maximum body size among insular Komodo dragon populations covaries with large prey density. Oikos 112:422–429CrossRefGoogle Scholar
  29. Jessop TS, Madsen T, Ciofi C et al (2007) Island differences in population size structure and catch per unit effort and their conservation implications for Komodo dragons. Biol Conserv 135:247–255CrossRefGoogle Scholar
  30. Jetz W, Carbone C, Fulford J et al (2004) The scaling of animal space use. Science 306(5694):266–268CrossRefPubMedGoogle Scholar
  31. Jones M (1997) Character displacement in Australian dasyurid carnivores: size relationships and prey size patterns. Ecology 78:2569--2587Google Scholar
  32. Kenward RE (1996) Ranges V: an analysis system for biological location data. Institute of Terrestrial Ecology, WarehamGoogle Scholar
  33. Lande R (1993) Risks of population extinction from demographic and environmental stochasticity and random catastrophes. Am Nat 142:911–927CrossRefGoogle Scholar
  34. Laundré JW (2010) Behavioral response races, predator-prey shell games, ecology of fear, and patch use of pumas and their ungulate prey. Ecology 91(10):2995–3007CrossRefPubMedGoogle Scholar
  35. Laundré JW, Reynolds TD, Knick ST et al (1987) Accuracy of daily point relocations in assessing areal movement of radio-marked animals. J Wildl Manag 51:937–940CrossRefGoogle Scholar
  36. Laver RJ, Purwandana D, Ariefiandy A et al (2012) Life-history and spatial determinants of somatic growth dynamics in Komodo dragon populations. PLoS One 7(9):e45398CrossRefPubMedPubMedCentralGoogle Scholar
  37. MacArthur RH, Pianka ER (1966) On optimal use of a patchy environment. Am Nat 100:603–609CrossRefGoogle Scholar
  38. Mace GM, Harvey PH (1983) Energetic constraints on home-range size. Am Nat 121:120–132CrossRefGoogle Scholar
  39. McCauley E, Wilson W, de Roos A (1996) Dynamics of age-structured predator-prey populations in space: asymmetrical effects of mobility in juvenile and adult predators. Oikos 76:485–497CrossRefGoogle Scholar
  40. McCurry MR, Mahony M, Clausen PD, Quayle MR, Walmsley CW, Jessop TS et al (2015) The relationship between cranial structure, biomechanical performance and ecological diversity in varanoid lizards. PLoS ONE 10(6):e0130625. doi: 10.1371/journal.pone.0130625 CrossRefPubMedPubMedCentralGoogle Scholar
  41. McNab BK (1963) Bioenergetics and the determination of home range size. Am Nat 97:133–140CrossRefGoogle Scholar
  42. Monk KA et al (1997) The ecology of Nusa Tenggara and Maluku. Oxford Univ. Press, OxfordGoogle Scholar
  43. Nifong JC, Layman CA, Silliman BR (2015) Size, sex and individual‐level behaviour drive intrapopulation variation in cross‐ecosystem foraging of a top‐predator. J Anim Ecol 84(1):35–48CrossRefPubMedGoogle Scholar
  44. Oksanen J, Blanchet FG, Kindt R et al (2011) Vegan: community ecology package. R Package Version 1:17–10Google Scholar
  45. Perry G, Garland T Jr (2002) Lizard home ranges revisited: effects of sex, body size, diet, habitat and phylogeny. Ecology 83:1870–1885CrossRefGoogle Scholar
  46. Pianka ER, Vitt LJ (2003) Lizards: windows to the evolution of diversity. University of California Press, BerkeleyGoogle Scholar
  47. Polis GA (1984) Age structure component of niche width and intraspecific resource partitioning—can age-groups function as ecological species. Am Nat 123:541–564CrossRefGoogle Scholar
  48. Pough FH (1980) The advantages of ectothermy for tetrapods. Am Nat 115:92–112CrossRefGoogle Scholar
  49. Purwandana D, Ariefiandy A, Imansyah MJ et al (2014) Demographic status of Komodo dragons populations in Komodo National Park. Biol Conserv 171:29–35CrossRefGoogle Scholar
  50. Purwandana D, Ariefiandy A, Imansyah MJ et al (2015) Evaluating environmental, demographic and genetic effects on population-level survival in an island endemic. Ecography. doi: 10.1111/ecog.01300 Google Scholar
  51. Radloff FGT, Du Toit JT (2004) Large predators and their prey in a southern African savanna: a predator’s size determines its prey size range. J Anim Ecol 73:410–423. doi: 10.1111/j.0021-8790.2004.00817.x CrossRefGoogle Scholar
  52. Ray JC, Sunquist ME (2001) Trophic relations in a community of African rainforest carnivores. Oecologia 127:395–408CrossRefGoogle Scholar
  53. Samuel MD, Fuller MR (1996) Wildlife radio-telemetry. In: Bookhout TA (ed) Research and management techniques for wildlife and habitats: 370–418. The Wildlife Society, BethesdaGoogle Scholar
  54. Schmidt-Nielsen K (1984) Scaling: why is animal size so important? Cambridge Univ. Press, CambridgeCrossRefGoogle Scholar
  55. Schoener TW (1968) Sizes of feeding territories among birds. Ecology 49(1):123–141CrossRefGoogle Scholar
  56. Schoener TW (1969) Models of optimal size for solitary predators. Am Nat 122:240–285CrossRefGoogle Scholar
  57. Schoener TW (1971) Theory of feeding strategies. Annu Rev Ecol Syst 2:369–404CrossRefGoogle Scholar
  58. Shine R (1986) Sexual differences in morphology and niche utilization in an aquatic snake, Acrochordus arafurae. Oecologia 69:260–267CrossRefGoogle Scholar
  59. Sih A (1998) Game theory and predator–prey response races. In: Dugatkin JA, Reeves HK (eds) Game theory and animal behavior. Oxford University Press, New York, pp 221–238Google Scholar
  60. Sims DW, Southall EJ, Humphries N, Hays GC, Bradshaw CJA, Pitchford JW et al (2008) Scaling laws of marine predator search behaviour. Nature 451:1098–1102CrossRefPubMedGoogle Scholar
  61. Swanson HK, Lysy M, Power M et al (2015) A new probabilistic method for quantifying n-dimensional ecological niches and niche overlap. Ecology 96:318–324CrossRefPubMedGoogle Scholar
  62. Taylor JA (1979) The foods and feeding habits of subadult Crocodylus porosus Schneider in northern Australia. Wildl Res 6:347--59Google Scholar
  63. Thompson G, De Boer M, Pianka ER (1999) Activity areas and daily movements of an arboreal monitor lizard, Varanus tristis (Squamata: Varanidae) during the breeding season. Aust J Ecol 24:117–122CrossRefGoogle Scholar
  64. Tucker AD, Limpus CJ, McCallum HI, McDonald KR (1996) Ontogenetic dietary partitioning by Crocodylus johnstoni during the dry season. Copeia 1996:978–988Google Scholar
  65. Viswanathan GM, da Luz MGE, Raposo EP, Stanley H (2011) The physics of foraging. Cambridge University Press, New YorkCrossRefGoogle Scholar
  66. Werner EE, Gilliam JF (1984) The ontogenetic niche and species interactions in size-structured populations. Annu Rev Ecol Syst 15:393–425CrossRefGoogle Scholar
  67. Werner EE, Hall DJ (1988) Ontogenetic habitat shifts in bluegill: the foraging rate-predation risk trade-off. Ecology 69:1352–1366Google Scholar
  68. White GC, Garrott RA (1990) Analysis of wildlife radio-tracking data. Academic, San DiegoGoogle Scholar
  69. Wood SN (2006) Generalized additive models: an introduction with R. Chapman and Hall/CRC Press, Boca RatonGoogle Scholar
  70. Wood S (2010) Package mgcv. R Package Version 1:8–9Google Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2016

Authors and Affiliations

  • Deni Purwandana
    • 1
  • Achmad Ariefiandy
    • 1
  • M. Jeri Imansyah
    • 1
  • Aganto Seno
    • 2
  • Claudio Ciofi
    • 3
  • Mike Letnic
    • 4
  • Tim S. Jessop
    • 5
    Email author
  1. 1.Komodo Survival ProgramDenpasarIndonesia
  2. 2.Komodo National ParkLabuan BajoIndonesia
  3. 3.Department BiologyUniversity of FlorenceSesto FiorentinoItaly
  4. 4.Centre for Ecosystem Science, School of Biological, Earth and Environmental SciencesUniversity of New South WalesKensingtonAustralia
  5. 5.Centre for Integrative Ecology, School of Life and Environmental SciencesDeakin UniversityWaurn PondsAustralia

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