My early research interests focused on reef fish ecology and behaviour, particularly the interface between fishes and their habitat. Upon joining the Long-Term Monitoring Program (LTMP) in 2004, my research focus shifted to quantifying the spatio-temporal patterns of distribution, abundance and diversity of reef fishes, how disturbances shape and influence reef fish assemblages and the effectiveness of management zoning on coral reefs of the Great Barrier Reef (GBR). The LTMP also reports on the condition and trends of GBR coral reefs and provides robust scientific information to managers and policy makers.
Status and trend of GBR reefs
Information from LTMP has been instrumental in apprising the Great Barrier Reef Marine Park Authority (GBRMPA), government and stakeholders on the status of the GBR and uses web-based reporting products to ensure timely dissemination of information upon completion of each survey cruise. Upon completion of each field season, an online annual update on the status of the GBR is produced, along with substantial media exposure.
LTMP data also feeds directly into the five yearly GBR Outlook Report produced by the GBRMPA under the auspices of the Australian Governments Reef 2050 Sustainability Plan.
Spatio-Temporal patterns in reef fishes
One of the fundamental goals in ecology is to understand how populations and communities are distributed and structured. Such information is crucial for management, conservation and determining how coral reefs are altered in response to anthropogenic and natural stressors. Data from the LTMP enabled an assessment of the fundamental distribution and abundance patterns of coral and reef fish assemblages across the majority of the GBR province. The most consistent spatial pattern in GBR reef fishes from LTMP data was a partitioning of the assemblage structure across the continental shelf. There have been distinct inshore, mid-shelf and outer-shelf assemblages identified for all groups of fishes examined
Effects of zoning
Evidence for beneficial effects of the initial zoning plan of the Great Barrier Reef Marine Park (GBRMP)1983-2004) was not universal and the expansion of the area of No-Take Marine Reserves (NTMRs) following the 2004 re-zoning of the Park was a bold social and political move that was highly controversial. Thus, it was important to demonstrate tangible benefits of the move. A collaboration with colleagues from James Cook University revealed rapid and significant increase in the density, length and biomass of coral trout in NTMRs compared to reefs that remained open to fishing, and these effects persist to this day. A later study also demonstrated that NTMRs can increase the resilience of coral reef assemblages to natural disturbance regimes.
Disturbance and recovery of coral and fish assemblages
Disturbances play a fundamental role in structuring many ecological communities. Data from the LTMP has provided pivotal information on the effects of disturbance regimes on the status and health of the GBR. A series of papers revealed that sub-regional trends in hard coral cover were diverse, with some being very dynamic while others changed very little, and that disturbances have differential effects on benthic assemblages of coral reefs, particularly hard corals. Habitat complexity has been shown to be an important driver of reef fish assemblage structure and the largest declines in the abundance and diversity of reef fishes occurred on reefs where both coral cover and complexity has been reduced. An examination of recovery dynamics revealed that hard coral cover on reefs in two disparate areas of the GBR recovered at similar rates, however differences in the underlying reef matrix rugosity was influential in how the recovery of associated fish assemblages progressed.
Herbivorous fishes
The replacement of corals by macroalgae is globally considered a sign of reef degradation. An understanding of the mechanisms that drive and sustain such phase shifts is relevant to reef managers, and the LTMP data have been applied to this field in different ways. In 2010 the LTMP reported that an ongoing 7-year phase shift at an inshore reef was strongly associated with a depauperate herbivorous fish community: particularly related to low general diversity and very low abundances of two functional groups. Another study found that the phase shift threat based on herbivore functionality varied throughout the GBR, being strongest on turbid inshore reefs, and that certain environmental factors could act in concert to lower or raise resilience thresholds.
Emslie, M.J., Logan, M., Bray, P., Ceccarelli, D.M., Cheal, A.J., Hughes, T.P., Johns, K.A., Jonker, M.J., Kennedy, E.V., Kerry, J.T. and Mellin, C., (2024). Increasing disturbance frequency undermines coral reef recovery. Ecological Monographs, 94(3) e1619. https://doi.org/10.1002/ecm.1619
Ruiz‐Moreno, A., Emslie, M.J. and Connolly, S.R., (2024). High response diversity and conspecific density‐dependence, not species interactions, drive dynamics of coral reef fish communities. Ecology Letters, 27(4), p.e14424.
Emslie, M.J., Ceccarelli, D.M., Logan, M., Blandford, M.I., Bray, P., Campili, A., Jonker, M.J., Parker, J.G., Prenzlau, T. and Sinclair-Taylor, T.H., (2024). Changing dynamics of Great Barrier Reef hard coral cover in the Anthropocene. Coral Reefs, pp.1-16.
Pratchett, M.S., Chandler, J.F., Choukroun, S.M., Doll, P.C., Lang, B.J., Kwong, S., Chen, C.C., Emslie, M.J., Caballes, C.F., Uthicke, S. and Matthews, S.A., (2024). Biophysical Processes Involved in the Initiation and Spread of Population Irruptions of Crown-of-Thorns Starfish on the Great Barrier Reef. In Oceanographic Processes of Coral Reefs (pp. 290-305). CRC Press.
Benedetti-Cecchi, L., Bates, A.E., Strona, G., Bulleri, F., Horta e Costa, B., Edgar, G.J., Hereu, B., Reed, D.C., Stuart-Smith, R.D., Barrett, N.S., Kushner, D.J., Emslie, M.J., García-Charton, J.A., Gonçalves, E.J., & Aspillaga, E. (2024). Marine protected areas promote stability of reef fish communities under climate warming. Nature Communications, 15(1), p.1822.
Pell, T.J., McClure, E.C., Emslie, M.J. and Hoey, A.S. (2024). Limited susceptibility of Lobophora to browsing fishes on inshore reefs of the Great Barrier Reef. Coral Reefs, 43(1), pp.5-17.
Edgar, G.J., Stuart-Smith, R.D., Heather, F.J., Barrett, N.S., Turak, E., Sweatman, H., Emslie, M.J., Brock, D.J., Hicks, J., French, B. and Baker, S.C., (2023). Continent-wide declines in shallow reef life over a decade of ocean warming. Nature, 615(7954), pp.858-865.
Benthuysen, J.A., Emslie, M.J., Currey-Randall, L.M., Cheal, A.J. and Heupel, M.R., (2022). Oceanographic influences on reef fish assemblages along the Great Barrier Reef. Progress in Oceanography, 208, p.102901.
Stuart-Smith, R.D., Edgar, G.J., Clausius, E., Oh, E.S., Barrett, N.S., Emslie, M.J., Bates, A.E., Bax, N., Brock, D., Cooper, A. and Davis, T.R., (2022). Tracking widespread climate-driven change on temperate and tropical reefs. Current Biology, 32(19), pp.4128-4138.
Kroon, F.J., Barneche, D.R. and Emslie, M.J., (2021). Fish predators control outbreaks of Crown-of-Thorns Starfish. Nature Communications, 12(1), p.6986.
Cheal, A.J., Emslie, M.J., Currey-Randall, L.M. and Heupel, M.R., (2021). Comparability and complementarity of reef fish measures from underwater visual census (UVC) and baited remote underwater video stations (BRUVS). Journal of Environmental Management, 289, p.112375.
Ceccarelli, D.M., McLeod, I.M., Boström-Einarsson, L., Bryan, S.E., Chartrand, K.M., Emslie, M.J., Gibbs, M.T., Gonzalez Rivero, M., Hein, M.Y., Heyward, A. and Kenyon, T.M., (2020). Substrate stabilisation and small structures in coral restoration: State of knowledge, and considerations for management and implementation. PloS ONE, 15(10), p.e0240846.
Emslie, M.J., Bray, P., Cheal, A.J., Johns, K.A., Osborne, K., Sinclair-Taylor, T. and Thompson, C.A., (2020). Decades of monitoring have informed the stewardship and ecological understanding of Australia's Great Barrier Reef. Biological Conservation, 252, p.108854.
Madin, E.M., Madin, J.S., Harmer, A.M., Barrett, N.S., Booth, D.J., Caley, M.J., Cheal, A.J., Edgar, G.J., Emslie, M.J., Gaines, S.D. and Sweatman, H.P., (2020). Latitude and protection affect decadal trends in reef trophic structure over a continental scale. Ecology and Evolution, 10(14), pp.6954-6966.
Cheal, A.J. and Emslie, M.J., 2020. Counts of coral reef fishes by an experienced observer are not biased by the number of target species. Journal of Fish Biology, 97(4), pp.1063-1071.
Emslie MJ (2019) Status and trends of hard coral cover in the northern Great Barrier Reef. A final report prepared for the Great Barrier Reef Foundation. AIMS Townsville.
Emslie MJ, Logan M, Cheal AJ. (2019) The distribution of planktivorous damselfishes (Pomacentridae) on the Great Barrier Reef and the relative influences of habitat and predationi. Diversity 11:33
Mellin C, Thompson A, Jonker MJ, Emslie MJ. (2019) Cross-shelf variation in coral community response to disturbance on the Great Barrier Reef. Diversity 11:38
Pratchett MS, Bridge TCL, Brodie J, Cameron DS, Day JC, Emslie MJ, Grech A, Hamann M, Heron SF, Hoey AS, Hoogenboom MO, Lough JM, Morrison TH, Osborne K, Read MA, Schauble C, Smithers SG, Sweatman HPA, Waterhouse J. (2019) Australia’s Great Barrier Reef. In World Seas: An environmental evaluation. Vol II the Indian Ocean to the Pacific. 2nd Edition. Ed. Charles Sheppard, Academic Press, London UK.
Cheal, A. J., M. J. Emslie. (2018) Synopsis of current coral reef monitoring on the Great Barrier Reef. Supplementary Report S3 to Final Report of the Coral Reef Expert Group. Report provided to GBRMPA.
Bierwagon SL, Emslie MJ, Heupel MR, Chin A, Simpfendorfer CA. (2018) Reef-scale variability in fish and coral assemblages on the central Great Barrier Reef.
Johns KJ, Emslie MJ, Hoey AS, Osborne K, Jonker MJ, Cheal AJ. (2018) Macroalgal feedbacks and substrate proprties maintain a coral reef regime shift. Ecoshere 9(7):e02349 Emslie MJ, Cheal AJ, MacNeil MA, Miller IR, Sweatman HPA (2018) Reef fish communities are spooked by scuba surveys and may take hours to recover. PeerJ6:e4886
Osborne K, Thompson AA, Cheal AJ, Emslie MJ, Johns KA, Jonker MJ, Logan M, Miller IR, Sweatman HPA. (2017) Delayed coral recovery in a warming ocean. Global Change Biology 23(9): 3869-3881.
Emslie MJ, Logan M, Cheal AJ. (2017) The distribution and abundance of reef-associated predatory fishes on the Great Barrier Reef. Coral Reefs 36(3): 829-846
Carter AB, Davies CR, Emslie MJ, Mapstone BD, Russ GR, Tobin AJ, Williams AJ (2017) Reproductive benefits of no-take marine reserves vary with region for an exploited coral reef fish. Scientific Reports 7(1): 9693
Cheal AJ, MacNeil MA, Emslie MJ, Sweatman HPA (2017) The threat to coral reefs from more intense cyclones under climate change. Global Change Biology 23 (4): 1511-1524
Emslie MJ (2016) Effects of habitat versus fisheries management on spatio-temporal variation in fish assemblages on the Great Barrier Reef. PhD by Prior Publication. Centre of Excellence for Coral Reef Studies, James Cook University.
Brandl SJ, Emslie MJ, Ceccarelli DM, Richards ZT. (2016) Habitat degradation increases functional originality in highly diverse coral reef fish assemblages. Ecosphere 7(11):e01557
Ceccarelli DM, Emslie MJ, Richards ZT. (2016) Post-disturbance stability of fish assemblages measured at coarse taxonomic resolution masks change at finer scales. PloS one 11(6): e0156232
Mellin C, MacNeil MA, Cheal AJ, Emslie MJ, Caley MJ. (2016) Marine protected areas increase resilience among coral reef communities. Ecology Letters 19 (6): 629-637.
Evans-Illidge EA, Tonin H, Lawrey E, Miller I, Steinberg C, Johns K, Emslie M, Brinkman R. (2016) Preliminary baseline knowledge to support a first-stage marine-environmental assessment of proposed in-sea desalination pipeline infrastructure at Great Palm Island (Bwgcolman), Queensland. Supplementary Report - the Northern Site. Report prepared for Palm Island Aboriginal Shire Council and the Queensland Department of Infrastructure, Local Government and Planning. Australian Institute of Marine Science, Townsville (60pp)
Emslie MJ, Logan M, Williamson DH, Ayling, AM, MacNeil MA, Ceccarelli DM, Cheal AJ, Evans RD, Johns KA, Jonker MJ, Miller IR, Osborne K, Russ GR, Sweatman HPA (2015) Expectation and outcomes of Reserve network performance following rezoning of the Great Barrier Reef Marine Park. Current Biology 25: 983-992
Miller I, Sweatman H, Cheal A, Emslie M, Johns K, Jonker M, Osborne K (2015) Origins and implications of a primary crown-of-thorns starfish outbreal in the southern Great Barrier Reef. J Marine Biology Volume 2015, Article ID 809624, 10 pages http://dx.doi.org/10.1155/2015/809624
Emslie MJ, Cheal AJ, Johns KA (2014) Retention of Habitat Complexity Minimizes Disassembly of Reef Fish Communities following Disturbance: A Large Scale Natural Experiment. PLoS ONE 9(8): e105384. doi:10.1371/journal.pone.0105384
Hobbs J-PA, Berger M, De Brauwer M, Emslie MJ (2014) North-eastern range extension of the anemone Stichodactyla haddoni to the Marshall Islands represents a new record of host use by the endemic anemonefish Amphiprion tricinctus. Marine Biodiversity Records 7: e106 DOI:10.1017/S1755267214001055
Feary DA, Pratchett MS, Emslie MJ, Fowler AM, Figueira WF, Luiz OJ, Nakamura Y, Booth DJ. (2014) Latitudinal shifts in coral reef fishes: why some species do and others do not shift. Fish & Fisheries 15: 593-615 DOI: 10.1111/faf.12036
Ceccarelli DM, Emslie MJ, Lewis AR (2013) Farming versatility by Pomacentrus wardi. Marine and Freshwater Research 64: 558-561 http://dx.doi.org/10.1071/MF12343
Cheal AJ, Emslie MJ, MacNeil MA, Miller I, Sweatman HPA (2013) Spatial variation in the functional characteristics of herbivorous fish communities and the resilience of coral reefs. Ecological Applications 23: 174-188 doi 10.1890/11-2253.1
Emslie MJ, Logan M, Ceccarelli DM, Cheal AJ, Hoey AS, Miller I, Sweatman HPA (2012) Regional scale variation in the distribution and abundance of farming damselfishes on Australia’s Great Barrier Reef. Marine Biology 159:1293-1304
Ian Miller, Alistair Cheal, Mike Emslie, Murray Logan and Hugh Sweatman. (2012) Ongoing effects of no-take marine reserves on commercially exploited coral trout populations on the Great Barrier Reef. Marine Environmental Research 79: 167 - 170
Andrew H Baird, Michael J Emslie, Andew R Lewis (2012) Extended periods of coral recruitment on the Great Barrier Reef. Proceedings of the 12th International Coral Reef Symposium, Cairns, Australia. 12A Life histories and reproduction.
Cheal AJ, Emslie MJ, Miller I, Sweatman HAS (2012) The distribution of herbivorous fishes on the Great Barrier Reef. Marine Biology 159: 1143-1154 doi 10.1007/s00227-012-1893-x
Cappo M, Stowar M, Lawrey E, MacNeil MA, Emslie MJ (2011) The influence of zoning (closure to fishing) on fish communities of the shoals and reef bases of the Great Barrier Reef Marine Park. Complementary analysis of observations from divers and baited video surveys to quantify the influence of region, habitat and zoning with extension of results to regional groups. Marine and Tropical Sciiences Research Facility (MTSRF) Transition Project Final Report. Reef and Rainforest Research Centre Limited, Cairns (50pp).
Beger M., Richards Z.T., Jacobson D., Emslie M. & Hess D. (2011). Majuro Atoll temporal monitoring report, 2010. Report to NOAA. In. College of the Marshall Islands, Australian Museum, The University of Queensland Majuro, Republic of the Marshall Islands, p. 25.
Emslie MJ, Pratchett MS, Cheal AJ (2011) The effect of different disturbance types on butterflyfish communities of Australia’s Great Barrier Reef. Coral Reefs 30: 461 – 471.
A. J. Cheal, M. Aaron Macneil, E. Cripps, M. J. Emslie, M. Jonker, B. Schaffelke, H. Sweatman (2010) Coral-macroalgal phase shifts or reef resilience: links with diversity and functional roles of herbivorous fishes on the Great Barrier Reef. Coral Reefs 29: 1005 - 1015
Emslie MJ, Pratchett MS, Cheal AJ, Osborne K (2010) Great Barrier Reef community structure: the role of shelf position and benthic community type. Coral Reefs 29: 705 - 715
Wilson SK, Dolman A, Cheal AJ, Emslie MJ, Pratchett MP and Sweatman HPA (2009) Maintenance of fish diversity on disturbed coral reefs. Coral Reefs 28:3-14.
Cheal AJ, Wilson SK, Emslie MJ, Dolman A and Sweatman HPA (2008) Responses of reef fish communities to coral declines on the Great Barrier Reef. Marine Ecology Progress Series 372: 211 - 223
Sweatman HPA, Cheal AJ, Coleman GJ, Emslie MJ, Johns K, Jonker M, Miller IR and Osborne K (2008) Long-term Monitoring of the Great Barrier reef, Status Report. 8. Australian Institute of Marine Science. 369 p.
Miller IR, Davidson J, Emslie MJ, Robertson C and Zagorskis IE (2008) Shallow-slope benthic surveys: Coral video/stills transects Scott Reef LTMP sites. Report prepared for Woodside Browse LNG Development. Australian Institute of Marine Science. 16 p.
Miller IR, Davidson J, Emslie MJ, Robertson C and Zagorskis IE (2008) Maxima 3D Surveys at Scott Reef. Fish Monitoring Program. Field Data Report on Trip 2 - Underwater Visual Census (UVC). Australian Institute of Marine Science and Environmental Resources Management Australia. 18 p
Russ GR, Cheal AJ, Dolman AM, Emslie MJ, Evans RD, Miller I, Sweatman H, Williamson DH. (2008) Rapid increase in Fish Numbers follows the creation of World’s Largest Marine Reserve Network. Current Biology 18: 514 – 515.
Emslie MJ, Cheal AJ, Delean S and Sweatman H. (2008 ) “Recovery of coral and reef fish communities following disturbance on the Great Barrier Reef Australia.” Marine Ecology Progress Series 371: 177-190.
Wilson S, Burgess S, Cheal A, Emslie M, Fisher R, Miller I, Polunin N and Sweatman H. (2008) "Habitat utilisation by coral reef fish: implications for specialists vs generalists in a changing environment" Journal of Animal Ecology. 77:220-228
Evans RD, Williamson DH, Sweatman H, Russ GR, Emslie M, Cheal A & Miller I. (2006) “Surveys of the effects of re-zoning of then GBR Marine Park on some fish species – preliminary findings. Unpublished report to the Australian Government Department of Environment and Heritage. 18pp.
Sweatman H, Burgess S, Cheal A, Coleman G, Delean S, Emslie M, Miller I, Osborne K, MacDonald A and Thompson A. (2005) Long Term Monitoring of the Great Barrier Reef. Status Report No. 7. Australian Institute of Marine Science.
Oxley W, Emslie M, Muir P and Thompson A. (2004a) Marine surveys undertaken in the Lihou Reef National Nature Reserve March 2004. Australian Institute of Marine Science
Oxley W, Emslie M, Osborne K and Speare P. (2004b) An Assessment of Effects of a Coral Bleaching Event at Lihou Reef National Nature Reserve, October 2004. Australian Institute of Marine Science
Sweatman H, Abdo D, Burgess S, Cheal A, Coleman G, Delean S, Emslie M, Miller I, Osborne K, Oxley W, Page C and Thompson A. (2003) Long Term Monitoring of the Great Barrier Reef. Status Report No. 6. Australian Institute of Marine Science.
Emslie MJ & Williamson DH (2003). Visual assessment of the marine habitats adjacent to the freshwater pipeline between Cape Pallerenda & Magnetic Island. Unpublished report prepared by Scientific Marine for Maunsell Australia Pty Ltd.
Ryan CM, Emslie MJ and Williamson DH. (2002) “Assessment of the seagrass, mangrove and coral reef communities at Radical Bay Magnetic Is NQ. Unpublished report by Scientific Marine to C & B Group.
Emslie MJ & Jones GP (2001) “Patterns of embryo mortality in a demersally spawning coral reef fish and the role of predatory fishes.” Environmental Biology of Fishes 60: 363-373 Jones GP, Milicich MJ, Emslie MJ and Lunow C (1999) “Self-recruitment in a coral reef fish population.” Nature 402: 802-804.
Emslie MJ (1995) “Patterns of reproductive success in a demersally spawning coral reef fish” Unpubl. Honours Thesis, James Cook University
