All Publications

  • Transformation of coral communities subjected to an unprecedented heatwave is modulated by local disturbance. Science advances Baum, J. K., Claar, D. C., Tietjen, K. L., Magel, J. M., Maucieri, D. G., Cobb, K. M., McDevitt-Irwin, J. M. 2023; 9 (14): eabq5615


    Corals are imminently threatened by climate change-amplified marine heatwaves. However, how to conserve coral reefs remains unclear, since those without local anthropogenic disturbances often seem equally or more susceptible to thermal stress as impacted ones. We disentangle this apparent paradox, revealing that the relationship between reef disturbance and heatwave impacts depends upon the scale of biological organization. We show that a tropical heatwave of globally unprecedented duration (~1 year) culminated in an 89% loss of hard coral cover. At the community level, losses depended on pre-heatwave community structure, with undisturbed sites, which were dominated by competitive corals, undergoing the greatest losses. In contrast, at the species level, survivorship of individual corals typically declined as local disturbance intensified. Our study reveals both that prolonged heatwaves projected under climate change will still have winners and losers and that local disturbance can impair survival of coral species even under such extreme conditions.

    View details for DOI 10.1126/sciadv.abq5615

    View details for PubMedID 37018404

  • Wave exposure shapes reef community composition and recovery trajectories at a remote coral atoll CORAL REEFS Lange, I. D., Benkwitt, C. E., McDevitt-Irwin, J. M., Tietjen, K. L., Taylor, B., Chinkin, M., Gunn, R. L., Palmisciano, M., Steyaert, M., Wilson, B., East, H. K., Turner, J., Graham, N. J., Perry, C. T. 2021
  • Coupled beta diversity patterns among coral reef benthic taxa. Oecologia McDevitt-Irwin, J. M., Kappel, C. n., Harborne, A. R., Mumby, P. J., Brumbaugh, D. R., Micheli, F. n. 2021


    Unraveling the processes that drive diversity patterns remains a central challenge for ecology, and an increased understanding is especially urgent to address and mitigate escalating diversity loss. Studies have primarily focused on singular taxonomic groups, but recent research has begun evaluating spatial diversity patterns across multiple taxonomic groups and suggests taxa may have congruence in their diversity patterns. Here, we use surveys of the coral reef benthic groups: scleractinian corals, macroalgae, sponges and gorgonians conducted in the Bahamian Archipelago across 27 sites to determine if there is congruence between taxonomic groups in their site-level diversity patterns (i.e. alpha diversity: number of species, and beta diversity: differences in species composition) while accounting for environmental predictors (i.e. depth, wave exposure, market gravity (i.e. human population size and distance to market), primary productivity, and grazing). Overall, we found that the beta diversities of these benthic groups were significant predictors of each other. The most consistent relationships existed with algae and coral, as their beta diversity was a significant predictor of every other taxa's beta diversity, potentially due to their strong biotic interactions and dominance on the reef. Conversely, we found no congruence patterns in the alpha diversity of the taxa. Market gravity and exposure showed the most prevalent correlation with both alpha and beta diversity for the taxa. Overall, our results suggest that coral reef benthic taxa can have spatial congruence in species composition, but not number of species, and that future research on biodiversity trends should consider that taxa may have non-independent patterns.

    View details for DOI 10.1007/s00442-020-04826-2

    View details for PubMedID 33394129

  • A review of a decade of lessons from one of the world's largest MPAs: conservation gains and key challenges MARINE BIOLOGY Hays, G. C., Koldewey, H. J., Andrzejaczek, S., Attrill, M. J., Barley, S., Bayley, D. I., Benkwitt, C. E., Block, B., Schallert, R. J., Carlisle, A. B., Carr, P., Chapple, T. K., Collins, C., Diaz, C., Dunn, N., Dunbar, R. B., Eager, D. S., Engel, J., Embling, C. B., Esteban, N., Ferretti, F., Foster, N. L., Freeman, R., Gollock, M., Graham, N. J., Harris, J. L., Head, C. I., Hosegood, P., Howell, K. L., Hussey, N. E., Jacoby, D. P., Jones, R., Pilly, S., Lange, I. D., Letessier, T. B., Levy, E., Lindhart, M., McDevitt-Irwin, J. M., Meekan, M., Meeuwig, J. J., Micheli, F., Mogg, A. M., Mortimer, J. A., Mucciarone, D. A., Nicoll, M. A., Nuno, A., Perry, C. T., Preston, S. G., Rattray, A. J., Robinson, E., Roche, R. C., Schiele, M., Sheehan, E. V., Sheppard, A., Sheppard, C., Smith, A. L., Soule, B., Spalding, M., Stevens, G. W., Steyaert, M., Stiffel, S., Taylor, B. M., Tickler, D., Trevail, A. M., Trueba, P., Turner, J., Votier, S., Wilson, B., Williams, G. J., Williamson, B. J., Williamson, M. J., Wood, H., Curnick, D. J. 2020; 167 (11)
  • Field stations as sentinels of change FRONTIERS IN ECOLOGY AND THE ENVIRONMENT Micheli, F., Carlton, J., Pearse, J., Selgrath, J., Elahi, R., Watanabe, J., Mach, M., McDevitt-Irwin, J., Pearse, V., Burnett, N., Baxter, C. 2020; 18 (6): 320–21

    View details for DOI 10.1002/fee.2231

    View details for Web of Science ID 000554674700004

  • Increased diversity and concordant shifts in community structure of coral-associated Symbiodiniaceae and bacteria subjected to chronic human disturbance. Molecular ecology Claar, D. C., McDevitt-Irwin, J. M., Garren, M. n., Vega Thurber, R. n., Gates, R. D., Baum, J. K. 2020


    Coral-associated bacteria and endosymbiotic algae (Symbiodiniaceae spp.) are both vitally important for the biological function of corals. Yet little is known about their co-occurrence within corals, how their diversity varies across coral species, or how they are impacted by anthropogenic disturbances. Here, we sampled coral colonies (n = 472) from seven species, encompassing a range of life history traits, across a gradient of chronic human disturbance (n = 11 sites on Kiritimati (Christmas) atoll) in the central equatorial Pacific, and quantified the sequence assemblages and community structure of their associated Symbiodiniaceae and bacterial communities. Although Symbiodiniaceae alpha diversity did not vary with chronic human disturbance, disturbance was consistently associated with higher bacterial Shannon diversity and richness, with bacterial richness by sample almost doubling from sites with low to very high disturbance. Chronic disturbance was also associated with altered microbial beta diversity for Symbiodiniaceae and bacteria, including changes in community structure for both and increased variation (dispersion) of the Symbiodiniaceae communities. We also found concordance between Symbiodiniaceae and bacterial community structure, when all corals were considered together, and individually for two massive species, Hydnophora microconos and Porites lobata, implying that symbionts and bacteria respond similarly to human disturbance in these species. Finally, we found that the dominant Symbiodiniaceae ancestral lineage in a coral colony was associated with differential abundances of several distinct bacterial taxa. These results suggest that increased beta diversity of Symbiodiniaceae and bacterial communities may be a reliable indicator of stress in the coral microbiome, and that there may be concordant responses to chronic disturbance between these communities at the whole-ecosystem scale.

    View details for DOI 10.1111/mec.15494

    View details for PubMedID 32495958

  • Habitat and fishing control grazing potential on coral reefs FUNCTIONAL ECOLOGY Robinson, J. W., McDevitt-Irwin, J. M., Dajka, J., Hadj-Hammou, J., Howlett, S., Graba-Landry, A., Hoey, A. S., Nash, K. L., Wilson, S. K., Graham, N. J. 2020; 34 (1): 240–51
  • Variable interaction outcomes of local disturbance and El Ni(n)over-tildeo-induced heat stress on coral microbiome alpha and beta diversity CORAL REEFS McDevitt-Irwin, J. M., Garren, M., McMinds, R., Thurber, R., Baum, J. K. 2019; 38 (2): 331–45
  • Global patterns and impacts of El Nino events on coral reefs: A meta-analysis PLOS ONE Claar, D. C., Szostek, L., McDevitt-Irwin, J. M., Schanze, J. J., Baum, J. K. 2018; 13 (2): e0190957


    Impacts of global climate change on coral reefs are being amplified by pulse heat stress events, including El Niño, the warm phase of the El Niño Southern Oscillation (ENSO). Despite reports of extensive coral bleaching and up to 97% coral mortality induced by El Niño events, a quantitative synthesis of the nature, intensity, and drivers of El Niño and La Niña impacts on corals is lacking. Herein, we first present a global meta-analysis of studies quantifying the effects of El Niño/La Niña-warming on corals, surveying studies from both the primary literature and International Coral Reef Symposium (ICRS) Proceedings. Overall, the strongest signal for El Niño/La Niña-associated coral bleaching was long-term mean temperature; bleaching decreased with decreasing long-term mean temperature (n = 20 studies). Additionally, coral cover losses during El Niño/La Niña were shaped by localized maximum heat stress and long-term mean temperature (n = 28 studies). Second, we present a method for quantifying coral heat stress which, for any coral reef location in the world, allows extraction of remotely-sensed degree heating weeks (DHW) for any date (since 1982), quantification of the maximum DHW, and the time lag since the maximum DHW. Using this method, we show that the 2015/16 El Niño event instigated unprecedented global coral heat stress across the world's oceans. With El Niño events expected to increase in frequency and severity this century, it is imperative that we gain a clear understanding of how these thermal stress anomalies impact different coral species and coral reef regions. We therefore finish with recommendations for future coral bleaching studies that will foster improved syntheses, as well as predictive and adaptive capacity to extreme warming events.

    View details for PubMedID 29401493

  • A communal catalogue reveals Earth's multiscale microbial diversity NATURE Thompson, L. R., Sanders, J. G., McDonald, D., Amir, A., Ladau, J., Locey, K. J., Prill, R. J., Tripathi, A., Gibbons, S. M., Ackermann, G., Navas-Molina, J. A., Janssen, S., Kopylova, E., Vazquez-Baeza, Y., Gonzalez, A., Morton, J. T., Mirarab, S., Xu, Z., Jiang, L., Haroon, M. F., Kanbar, J., Zhu, Q., Song, S., Kosciolek, T., Bokulich, N. A., Lefler, J., Brislawn, C. J., Humphrey, G., Owens, S. M., Hampton-Marcell, J., Berg-Lyons, D., McKenzie, V., Fierer, N., Fuhrman, J. A., Clauset, A., Stevens, R. L., Shade, A., Pollard, K. S., Goodwin, K. D., Jansson, J. K., Gilbert, J. A., Knight, R., Earth Microbiome Project Consortiu 2017; 551 (7681): 457-+


    Our growing awareness of the microbial world's importance and diversity contrasts starkly with our limited understanding of its fundamental structure. Despite recent advances in DNA sequencing, a lack of standardized protocols and common analytical frameworks impedes comparisons among studies, hindering the development of global inferences about microbial life on Earth. Here we present a meta-analysis of microbial community samples collected by hundreds of researchers for the Earth Microbiome Project. Coordinated protocols and new analytical methods, particularly the use of exact sequences instead of clustered operational taxonomic units, enable bacterial and archaeal ribosomal RNA gene sequences to be followed across multiple studies and allow us to explore patterns of diversity at an unprecedented scale. The result is both a reference database giving global context to DNA sequence data and a framework for incorporating data from future studies, fostering increasingly complete characterization of Earth's microbial diversity.

    View details for DOI 10.1038/nature24621

    View details for Web of Science ID 000416043700036

    View details for PubMedID 29088705

  • Responses of coral-associated bacterial communities to local and global stressors Frontiers in Marine Science McDevitt-Irwin, J. M., Baum, J. K., Garren, M., Vega Thurber, R. L. 2017; 4 (262)

    View details for DOI 10.3389/fmars.2017.00262

  • Reassessing the nursery role of seagrass habitats from temperate to tropical regions: a meta-analysis MARINE ECOLOGY PROGRESS SERIES McDevitt-Irwin, J. M., Iacarella, J. C., Baum, J. K. 2016; 557: 133–43

    View details for DOI 10.3354/meps11848

    View details for Web of Science ID 000387114000010

  • Missing the safety net: evidence for inconsistent and insufficient management of at-risk marine fishes in Canada CANADIAN JOURNAL OF FISHERIES AND AQUATIC SCIENCES McDevitt-Irwin, J., Fuller, S., Grant, C., Baum, J. 2015; 72 (10): 1596–1608