Dr Tim Jessop is an integrative ecologist who studies the effects of environmental, ecological and anthropogenic disturbances on animal physiology, ecology and evolutionary biology. His primary research goal is to understand how disturbance processes act on the fitness of individuals to shape population and even community dynamics.
His research interests span two areas:
1. The significance of stress hormones in vertebrate ecology and evolution:
a) The acute stress response as a mediator of life-history trade-offs between survival and reproduction.
c) The role of glucortoicoid stress response in mediating species interactions.
d) Macro stress: Investigating large scale ecological processes for explaining species level variation in the glucocorticoid stress response.
e) Synthesis and development of conceptual understanding of the role of GC hormones in vertebrate ecology and evolution
2. Applied vertebrate ecology and conservation research: Tim believes that use of both ecological and evolutionary theory must form the basis to implementing environmental management to mitigate the impacts of global environmental change on biodiversity (including humanity). To that end, he undertakes research in applied ecology and evolution to understand risk, or efficacy of management, for influencing fate of animal individuals, populations and communities. Key examples include:
1. Island Endemic Ecology and Conservation of Komodo dragons
2. Evaluating efficacy of multiple landscape management process on terrestrial biodiversity.
3. Integrating empirical and predictive approaches for evaluating environmental management actions.
If possible I try to use highly integrative studies that investigate individual, population and community level processes to holistically understand how animals respond to their environment. Complimenting this multi-scale approach is to also adopt different methods drawn from landscape genetics, comparative physiology, population and behavioural ecology to further diversify data collection. The entire rational for this approach is to provide multi-modal inference to ensure cross-validation of knowledge across multiple tiers of research information. My belief is that such approaches are necessary to provide synthesis and help to define clearly the limitation of data for making informed inference to better advance value of pure and applied knowledge.
Students & Postdocs
Rebecca Laver (co-supervisor)
Animal Structure and Function
Australian Wildlife Biology
Comparative Animal Physiology
Experimental Animal Behaviour
MSc graduate Seminar (contributor)
MSc grant assignmentPublication
1. Jessop, T. S. and Ladds, P. W. (1995). Immunopathology of unilateral vasectomy in the ram. Journal of Veterinary Immunology and Immunopathology 47 (1-2): 123-133.
2. Jessop, T. S., FitzSimmon, N., Limpus, C. J., and Whittier, J. M. (1999). Interactions between behaviour and plasma steroids within the scramble mating system of the promiscuous green turtle, Chelonia mydas. Hormones and Behaviour 36: 86-97.
3. Jessop, T. S., Limpus, C. J., and Whittier, J. M. (1999). Plasma steroid interactions during high-density green turtle nesting and associated disturbance. General and Comparative Endocrinology 115: 90-100.
4. Jessop, T. S., Hamann, M., Read M., A. and Limpus, C. J. (2000). Evidence for a hormonal tactic maximising green turtle reproduction in response to a pervasive ecological stressor. General and Comparative Endocrinology 118 (3): 107-117.
5. Jessop, T. S. (2001). Modulation of the adrenocortical stress response in marine turtles: A hormonal tactic maximizing maternal reproductive investment. Journal of Zoology (London) 254: 57-65.
6. Jessop, T. S., Knapp, R., Limpus, C. J. and Whittier, J. M. (2002). Dynamic Endocrine Responses to Stress: Evidence for energetic constraints and status dependence of breeding in male green turtles. General and Comparative Endocrinology 126: 59-67.
7. Jessop, T. S., Limpus, C. J., and Whittier, J. M. (2002). Nocturnal activity in the green sea turtle alters daily profiles of melatonin and corticosterone. Hormones and Behavior 41: 357-365.
8. Hamann, M; Jessop, T. S., Limpus, C. J. and Whittier, J. M. (2002). Plasma steroid profiles of Nesting Green turtles. Relationship to nesting episode, season, and nesting experience. Marine Biology 140: 823-830.
9. Jessop, T. S., Tucker, A., Limpus, C. J. and Whittier, J. M. (2003) Interactions between ecology, demography, capture stress and profiles of corticosterone and glucose in a free-living population of Australian freshwater crocodiles. General and Comparative Endocrinology 132: 161-170.
10. Moore, I. T. and Jessop, T. S. (2003) Stress, reproduction, and adrenocortical modulation in amphibians and reptiles. Hormones and Behavior 43: 39-47.
11. Jessop, T. S., Sumner, J., Lance, V. and Limpus, C. (2004). Reproduction in shark attacked sea turtles is supported by stress reduction mechanisms. Proceeding of the Royal Society of London Biology 271: S91-S94.
12. Leary, C. J., Jessop, T. S., Garcia, A., and Knapp, R. (2004). Steroid hormone profiles and condition indices for calling and satellite toads: Implications for proximate regulation of behavioral phenotypes in the anura. Behavioural Ecology 15: 463-470.
13. Jessop, T. S., Sumner, J., Limpus, C. J. and Whittier, J. M. (2004). Interplay between sex, body condition and plasma hormone profiles in juvenile Hawksbill turtles subjected to a capture stress protocol. Journal of Comparative Physiology and Biochemistry A 137:197-204.
14. Jessop, T. S., Sumner, J. Imansyah, M. J., Puwandana, D., Rudiharto, H. and Phillips J. A. (2004). Distribution, use and selection of nest type by Komodo Dragons. Biological Conservation 117: 463-470.
15. Sumner, J, Jessop, T. S., Paetkau, D., and Moritz, C. (2004).The effect of anthropogenic habitat fragmentation on genetic diversity in the endemic rainforest skink Gynpetoscincus queenslandii. Molecular Ecology 13: 259-269.
16. Jessop, T. S., Limpus, C. J. and Whittier, J. M. (2004) Comparison of plasma testosterone profiles in Green and Hawksbill Sea Turtle inhabiting Queensland Waters. Australian Journal of Zoology 52:293-301.
17. Jessop, T. S., Hamann, M., and Limpus, C. J. (2004) Body condition, energy metabolite, and endocrine changes in male green turtles during breeding. Marine Ecology Progress Series 276: 281–288.
18. Jessop, T. S. and Hamann, M. (2004). Interactions between nesting activity and plasma profiles of catecholamines, corticosterone and metabolites in the green turtle, Chelonia mydas. Journal of Experimental Marine Biology and Ecology 308: 253– 267.
19. Jessop, T. S. and Hamann, M. (2005). Interplay between age class, sex and corticosterone stress responsiveness in green turtles (Chelonia mydas). Australian Journal of Zoology 53:131 -136.
20. Hamann, M., Jessop, T. S., Limpus C.J. (2005) Regional and annual variation in plasma steroids and metabolic indicators of non-breeding and breeding female green turtles. Marine Biology 148: 427-433.
21. Jessop, T. S., Madsen, T., Sumner, J., Rudiharto, H., Phillips, J. A. and Ciofi C. (2006) Maximum body size among insular Komodo dragon populations covaries with large prey density. Oikos 112: 22-429.
22. Lanyon, J.M., Slade, R.W., Sneath H.L, Broderick D., Kirkwood, J.M. Limpus, D. Limpus C.J., and Jessop T.S. (2006). A method for capturing dugongs (Dugong dugong) in open water. Aquatic Mammals 32(2):196-201.
23. Jessop, T. S., Madsen, T., Sumner, J., Rudiharto, H., Phillips, J. A. and Ciofi C. (2007). Differences in population size structure and body condition: Conservation implications for Komodo Dragons. Biological Conservation 135: 247–255.
24. Hamann, M., Jessop, T. S., Schauble, C. (2007). Profiles of plasma steroids and metabolic indicators during nest emergence and natal dispersal in Hatchling green turtles. Journal of Experimental Marine Biology and Ecology 353:13-21.
25. Jessop, T. and Imansyah J. (2008). Varanus komodoensis Parasites. Herpetological Review. 39: 96-97.
26. Imansyah, M.J, Jessop T.S., Ciofi, C., Akbar, Z. (2008). Ontogenetic differences in the spatial ecology of immature Komodo Dragons. Journal of Zoology 274: 107-115.
27. Jessop, T. S., Sahu A. and Opat D. (2008). Varanus komodoensis Occurence. Herpetological Review. 39 (1): 95-96.
28. Jessop, T.S., Imansyah, J., Purwandana, D., Ariefiandy, A. and Opat D (2008) Incidence of Fish Hook Ingestion by Komodo dragons. Biawak. 2008. 2(3): 121-123.
29. Imansyah, J. Purwandana, D and Jessop, T.S. (2008) First records of Wallace’s Hanging-parrot Loriculus flosculus from Rinca Island, Komodo National Park, Indonesia. Forktail 24:131-132.
30. Jessop T. S., Sumner, J. S., Purwandana, A., Imansyah J. and Argento S. ( 2009). Assessment of the distribution, seasonal use and predation risk of orange-footed scrubfowl nests on Komodo Island. Journal of Field Ornithology. 80:119-126
31. Jessop, T. S., Chan, R. and Stuart-Fox, D. (2009) Sex steroid correlates of female-specific coloration, behaviour and reproductive state in Lake Eyre dragons, Ctenophorus maculosus. Journal of Comparative Physiology A. 195: 619-630.
32. Chan, R., Stuart-Fox, D. and Jessop T.S. (2009) Why are females ornamented? A test of the courtship stimulation and courtship rejection hypotheses in the Lake Eyre dragon, Ctenophorus maculosus. Behavioural Ecology 20:1334-1340
33. Singh D.; Dixson B. J.; Jessop T. S.; Morgan B., and Dixson A.F. (2010) Cross-cultural attractiveness of the female hourglass figure. Evolution & Human Behavior 31:176-183.
34. Jessop, T. S., Sumner, J. Rudiharto, H., Phillips, J. A. and Ciofi C. (2010) Associations in the host-parasite dynamics between Komodo dragons and their ectoparasites. Australian Zoologist 35:122129.
35. Harlow, H., Purwandana D., Jessop T., Phillips J.(2010) Body temperature and thermoregulation of Komodo dragons in the field. Journal of Thermal Biology 35: 338-347.
36. Harlow, H., Purwandana D., Jessop T., Phillips J.(2010) Size-Related Differences in the Thermoregulatory Habits of Free-Ranging Komodo Dragons. International Journal of Zoology, 2010: doi:10.1155/2010/921371.
37. Bull, J.J., Jessop T. S., Whiteley M. (2010) Deathly Drool: Evolutionary and ecological basis of septic bacteria in Komodo Dragons Mouths. PLos One :e1097.doi:10.1371/journal.pone0011097.
38. Jessop T.S. Urlus J., Gillespie G. (2010) Preying possum: assessing the diet of lace monitors from forest of South Eastern Australia. Biawak 4: 59-66.
39. Lancaster P., Jessop T. S. and Stuart-Fox D. (2011) Testing the independent effects of population and shelter density on behavioral and corticosterone responses of tree skinks. Australian Journal of Zoology 58:, 295–302.
40. Scheelings F., and Jessop T.S (2011) Blood parameters of free-ranging Lace Monitors, Varanus varius: Are they influenced by capture method, habitat quality or individual status? Australian Veterinary Journal 89(9): 360-365.
41. Jessop T., Scheelings F. Dempster T. (2012) Meal ticket or last supper: Effects of a human mediated tropic subsidy on a large Australian predator. PLos One (4): e34069. doi:10.1371/journal.pone.0034069
42. Jessop T. S., Woodford R. & Matthew R. E. Symonds (2012) Macrostress: Do large-scale ecological patterns exist in the glucocorticoid stress response of vertebrates? Functional Ecology doi: 10.1111/1365-2435.12
43. Crespi, E. J., Williams, T. D., Jessop, T. S., Delehanty, B. (2012), Life history and the ecology of stress: how do glucocorticoid hormones influence life-history variation in animals?. Functional Ecology. doi: 10.1111/1365-2435.12009
44. Payne C. J., Jessop T. S,, Guay P.-J., Johnstone M., Feore M., et al. (2012) Population, Behavioural and Physiological Responses of an Urban Population of Black Swans to an Intense Annual Noise Event. PLoS ONE 7(9): e45014. doi:10.1371/journal.pone.0045014
45. Laver R. J., Purwandana D., Ariefiandy A., Imansyah J., Forsyth D, Jessop T.S. (2012) Life-History and Spatial Determinants of Somatic Growth Dynamics in Komodo Dragon Populations. PLoSONE 7(9): e45398. doi:10.1371/journal.pone.0045398
46. Ariefiandy A., Purwandana D., Coulson G., Forsyth D. and T. S. Jessop (2013). Using faecal counts and distance sampling to monitor the ungulate prey of Komodo dragons. Wildlife Biology 19: 1-12.
47. Jessop T. S.,. Kearney M. R., Moore J. L., Lockwood T. and Johnston M. (2013). Evaluating and predicting risk to a large reptile from feral cat baiting protocols. Biological Invasions 10.1007/s10530-012-0398-3 48.
48. Ariefiandy A., Purwandana D., Aganto S., Ciofi C. and Jessop T.S. (2013) Is camera trapping a suitable method enabling population inference in reptiles: A case study with Komodo dragons. PLoSONE (Accepted with revisions).
49. Anson J. R., Dickman C. R., Boonstra R, Jessop T. S. (2013) Stress triangle: Do introduced predators exert indirect costs on native predators and prey? PLoSONE (Accepted with revisions).
50. Smissen P. J., Melville J., Sumner J., Jessop T. S. (2013) Phylogeography and population genetics of Varanus varius: Evidence of rapid expansion and high gene flow in a mobile lizard. Journal of Biogeography. (Accepted with revisions).
51. Jessop T. S., Ciofi C., Purwandana, D., Ariefiandy, A., Imansyah J., Rudiharto H., Seno A., Gormley, A. M., Harlow H. J., Phillips, J. A., Forsyth D. M. (2013). Dispersal inertia renders Komodo dragons sensitive to extinction processes. Global Change Biology (Accepted with revisions).
52. Hu Y., Magaton S, Gillespie G. and Jessop T.S. (2013) Do disturbance theories predict small reptile community responses to logging? Biological Conservation. (Accepted with revisions).
Papers in review
53. Anson J. R., Dickman C. R., Boonstra R, Handasyde K., Jessop T. S. Predator-prey interactions under competing disturbance processes: arboreal vertebrates in south eastern Australian. (submitted Dec 12)
54. Jessop T.S., Dempster T., Letnic M., Webb J. Changes to daily endocrine profiles suggest toads evade shift work costs during nocturnal activity.
55. Y., Magaton S, Gillespie G. and Jessop T.S. Evaluating the role of fire disturbance in structuring small reptile communities in temperate forests.
56. Jessop T.S., Letnic M., Webb J., Dempster T. Stress hormones mediate adaptive phenotypic performance underpinning invasion success.
57. Ariefiandy A., Purwandana D., Aganto S., Ciofi C. and Jessop T.S. Evaluation of Komodo dragon population density estimates using two non-mark recapture based methods.
58. Ariefiandy A., Purwandana D., Aganto S., Ciofi C. and Jessop T.S. How do coupled body size and diet transitions influence home range area and use in Komodo dragons a solitary predator?
59. Jessop T. S., Ariefiandy A., Purwandana D., Aganto S., Ciofi C. And Laver R. Losing your head: negative somatic growth in Komodo dragons suggests a sex dependent ageing process?
Further Publications: PubMed Search