Current Research and Scholarly Interests

Fiorenza Micheli is a marine ecologist and conservation biologist conducting research and teaching at the Hopkins Marine Station of Stanford University, in California, USA, where she is Professor of Biology. Her research focuses on the processes shaping marine communities, and incorporating this understanding in the management and conservation of marine ecosystems. Current research focuses on responses of marine communities to climate change, and on the function of marine protected areas and other conservation and adaptation strategies in the face of climate impacts. She is the PI on the project “Enhancing resilience of coastal ecosystems and human communities to oceanographic variability: social and ecological feedbacks” funded by the National Science Foundation Coupled Natural-Human Systems. She received her undergraduate degree in natural sciences from the University of Florence, Italy, in 1988, and a PhD in marine sciences from the University of North Carolina at Chapel Hill, USA, in 1995. Between 1996-1999 she was a postdoctoral researcher at the National Center for Ecological Analysis and Synthesis, in Santa Barbara. She has conducted research in Italy, east Africa, Australia, the Bahamas, Mexico, California, and the Pacific Line Islands, in a suite of marine ecosystems including mangrove forests, seagrass beds, salt marshes, rocky reefs, coral reefs, pelagic systems, and deep sea hydrothermal vents. Professor Micheli has authored or co-authored 120 peer-reviewed publications, which have been cited 8299 times with an h-index of 41, according to Google Scholar. She is a fellow of the California Academy of Science and the Aldo Leopold Leadership Program, a Pew fellow in marine conservation, and past president of the Western Society of Naturalists.

2015-16 Courses

Stanford Advisees

All Publications

  • Reconciling predator conservation with public safety FRONTIERS IN ECOLOGY AND THE ENVIRONMENT Ferretti, F., Jorgensen, S., Chapple, T. K., De Leo, G., Micheli, F. 2015; 13 (8): 412-417

    View details for DOI 10.1890/150109

    View details for Web of Science ID 000362229100014

  • No-take marine reserves can enhance population persistence and support the fishery of abalone CANADIAN JOURNAL OF FISHERIES AND AQUATIC SCIENCES Rossetto, M., Micheli, F., Saenz-Arroyo, A., Espinoza Montes, J. A., Alessandro De Leo, G. 2015; 72 (10): 1503-1517
  • Towards a framework for assessment and management of cumulative human impacts on marine food webs CONSERVATION BIOLOGY Giakoumi, S., Halpern, B. S., Michel, L. N., Gobert, S., Sini, M., Boudouresque, C., Gambi, M., Katsanevakis, S., Lejeune, P., Montefalcone, M., Pergent, G., Pergent-Martini, C., Sanchez-Jerez, P., Velimirov, B., Vizzini, S., Abadie, A., Coll, M., Guidetti, P., Micheli, F., Possingham, H. P. 2015; 29 (4): 1228-1234


    Effective ecosystem-based management requires understanding ecosystem responses to multiple human threats, rather than focusing on single threats. To understand ecosystem responses to anthropogenic threats holistically, it is necessary to know how threats affect different components within ecosystems and ultimately alter ecosystem functioning. We used a case study of a Mediterranean seagrass (Posidonia oceanica) food web and expert knowledge elicitation in an application of the initial steps of a framework for assessment of cumulative human impacts on food webs. We produced a conceptual seagrass food web model, determined the main trophic relationships, identified the main threats to the food web components, and assessed the components' vulnerability to those threats. Some threats had high (e.g., coastal infrastructure) or low impacts (e.g., agricultural runoff) on all food web components, whereas others (e.g., introduced carnivores) had very different impacts on each component. Partitioning the ecosystem into its components enabled us to identify threats previously overlooked and to reevaluate the importance of threats commonly perceived as major. By incorporating this understanding of system vulnerability with data on changes in the state of each threat (e.g., decreasing domestic pollution and increasing fishing) into a food web model, managers may be better able to estimate and predict cumulative human impacts on ecosystems and to prioritize conservation actions.

    View details for DOI 10.1111/cobi.12468

    View details for Web of Science ID 000357981200029

    View details for PubMedID 25704365

  • Assessing niche width of endothermic fish from genes to ecosystem PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA Madigan, D. J., Carlisle, A. B., Gardner, L. D., Jayasundara, N., Micheli, F., Schaefer, K. M., Fuller, D. W., Block, B. A. 2015; 112 (27): 8350-8355


    Endothermy in vertebrates has been postulated to confer physiological and ecological advantages. In endothermic fish, niche expansion into cooler waters is correlated with specific physiological traits and is hypothesized to lead to greater foraging success and increased fitness. Using the seasonal co-occurrence of three tuna species in the eastern Pacific Ocean as a model system, we used cardiac gene expression data (as a proxy for thermal tolerance to low temperatures), archival tag data, and diet analyses to examine the vertical niche expansion hypothesis for endothermy in situ. Yellowfin, albacore, and Pacific bluefin tuna (PBFT) in the California Current system used more surface, mesopelagic, and deep waters, respectively. Expression of cardiac genes for calcium cycling increased in PBFT and coincided with broader vertical and thermal niche utilization. However, the PBFT diet was less diverse and focused on energy-rich forage fishes but did not show the greatest energy gains. Ecosystem-based management strategies for tunas should thus consider species-specific differences in physiology and foraging specialization.

    View details for DOI 10.1073/pnas.1500524112

    View details for Web of Science ID 000357527600063

  • Productivity and fishing pressure drive variability in fish parasite assemblages of the Line Islands, equatorial Pacific ECOLOGY Wood, C. L., Baum, J. K., Reddy, S. M., Trebilco, R., Sandin, S. A., Zgliczynski, B. J., Briggs, A. A., Micheli, F. 2015; 96 (5): 1383-1398
  • Spatio-temporal variability of polychaete colonization at volcanic CO2 vents indicates high tolerance to ocean acidification MARINE BIOLOGY Ricevuto, E., Kroeker, K. J., FERRIGNO, F., Micheli, F., Gambi, M. C. 2014; 161 (12): 2909-2919
  • Fabriciidae (Annelida, Sabellida) from a naturally acidified coastal system (Italy) with description of two new species JOURNAL OF THE MARINE BIOLOGICAL ASSOCIATION OF THE UNITED KINGDOM Giangrande, A., Gambi, M. C., Micheli, F., Kroeker, K. J. 2014; 94 (7): 1417-1427
  • Identifying the interacting roles of stressors in driving the global loss of canopy-forming to mat-forming algae in marine ecosystems GLOBAL CHANGE BIOLOGY Strain, E. M., Thomson, R. J., Micheli, F., Mancuso, F. P., Airoldi, L. 2014; 20 (11): 3300-3312


    Identifying the type and strength of interactions between local anthropogenic and other stressors can help to set achievable management targets for degraded marine ecosystems and support their resilience by identifying local actions. We undertook a meta-analysis, using data from 118 studies to test the hypothesis that ongoing global declines in the dominant habitat along temperate rocky coastlines, forests of canopy-forming algae and/or their replacement by mat-forming algae are driven by the nonadditive interactions between local anthropogenic stressors that can be addressed through management actions (fishing, heavy metal pollution, nutrient enrichment and high sediment loads) and other stressors (presence of competitors or grazers, removal of canopy algae, limiting or excessive light, low or high salinity, increasing temperature, high wave exposure and high UV or CO2 ), not as easily amenable to management actions. In general, the cumulative effects of local anthropogenic and other stressors had negative effects on the growth and survival of canopy-forming algae. Conversely, the growth or survival of mat-forming algae was either unaffected or significantly enhanced by the same pairs of stressors. Contrary to our predictions, the majority of interactions between stressors were additive. There were however synergistic interactions between nutrient enrichment and heavy metals, the presence of competitors, low light and increasing temperature, leading to amplified negative effects on canopy-forming algae. There were also synergistic interactions between nutrient enrichment and increasing CO2 and temperature leading to amplified positive effects on mat-forming algae. Our review of the current literature shows that management of nutrient levels, rather than fishing, heavy metal pollution or high sediment loads, would provide the greatest opportunity for preventing the shift from canopy to mat-forming algae, particularly in enclosed bays or estuaries because of the higher prevalence of synergistic interactions between nutrient enrichment with other local and global stressors, and as such it should be prioritized.

    View details for DOI 10.1111/gcb.12619

    View details for Web of Science ID 000343762800002

    View details for PubMedID 24771500

  • Positive and Negative Effects of a Threatened Parrotfish on Reef Ecosystems CONSERVATION BIOLOGY McCauley, D. J., Young, H. S., Guevara, R., Williams, G. J., Power, E. A., Dunbar, R. B., Bird, D. W., Durham, W. H., Micheli, F. 2014; 28 (5): 1312-?

    View details for DOI 10.1111/cobi.12314

    View details for Web of Science ID 000342668700001

  • Positive and negative effects of a threatened parrotfish on reef ecosystems. Conservation biology McCauley, D. J., Young, H. S., Guevara, R., Williams, G. J., Power, E. A., Dunbar, R. B., Bird, D. W., Durham, W. H., Micheli, F. 2014; 28 (5): 1312-1321


    Species that are strong interactors play disproportionately important roles in the dynamics of natural ecosystems. It has been proposed that their presence is necessary for positively shaping the structure and functioning of ecosystems. We evaluated this hypothesis using the case of the world's largest parrotfish (Bolbometopon muricatum), a globally imperiled species. We used direct observation, animal tracking, and computer simulations to examine the diverse routes through which B. muricatum affects the diversity, dispersal, relative abundance, and survival of the corals that comprise the foundation of reef ecosystems. Our results suggest that this species can influence reef building corals in both positive and negative ways. Field observation and simulation outputs indicated that B. muricatum reduced the abundance of macroalgae that can outcompete corals, but they also feed directly on corals, decreasing coral abundance, diversity, and colony size. B. muricatum appeared to facilitate coral advancement by mechanically dispersing coral fragments and opening up bare space for coral settlement, but they also damaged adult corals and remobilized a large volume of potentially stressful carbonate sediment. The impacts this species has on reefs appears to be regulated in part by its abundance-the effects of B. muricatum were more intense in simulation scenarios populated with high densities of these fish. Observations conducted in regions with high and low predator (e.g., sharks) abundance generated results that are consistent with the hypothesis that these predators of B. muricatum may play a role in governing their abundance; thus, predation may modulate the intensity of the effects they have on reef dynamics. Overall our results illustrate that functionally unique and threatened species may not have universally positive impacts on ecosystems and that it may be necessary for environmental managers to consider the diverse effects of such species and the forces that mediate the strength of their influence.

    View details for DOI 10.1111/cobi.12314

    View details for PubMedID 25065396

  • Reliance of mobile species on sensitive habitats: a case study of manta rays (Manta alfredi) and lagoons MARINE BIOLOGY McCauley, D. J., DeSalles, P. A., Young, H. S., Papastamatiou, Y. P., Caselle, J. E., Deakos, M. H., Gardner, J. P., Garton, D. W., Collen, J. D., Micheli, F. 2014; 161 (9): 1987-1998
  • A risk-based framework for assessing the cumulative impact of multiple fisheries BIOLOGICAL CONSERVATION Micheli, F., De Leo, G., Butner, C., Martone, R. G., Shester, G. 2014; 176: 224-235
  • Fishing drives declines in fish parasite diversity and has variable effects on parasite abundance ECOLOGY Wood, C. L., Sandin, S. A., Zgliczynski, B., Guerra, A. S., Micheli, F. 2014; 95 (7): 1929-1946


    Despite the ubiquity and ecological importance of parasites, relatively few studies have assessed their response to anthropogenic environmental change. Heuristic models have predicted both increases and decreases in parasite abundance in response to human disturbance, with empirical support for both. However, most studies focus on one or a few selected parasite species. Here, we assess the abundance of parasites of seven species of coral reef fishes collected from three fished and three unfished islands of the Line Islands archipelago in the central equatorial Pacific. Because we chose fish hosts that spanned different trophic levels, taxonomic groups, and body sizes, we were able to compare parasite responses across a broad cross section of the total parasite community in the presence and absence of fishing, a major human impact on marine ecosystems. We found that overall parasite species richness was substantially depressed on fished islands, but that the response of parasite abundance varied among parasite taxa: directly transmitted parasites were significantly more abundant on fished than on unfished islands, while the reverse was true for trophically transmitted parasites. This probably arises because trophically transmitted parasites require multiple host species, some of which are the top predators most sensitive to fishing impacts. The increase in directly transmitted parasites appeared to be due to fishing-driven compensatory increases in the abundance of their hosts. Together, these results provide support for the predictions of both heuristic models, and indicate that the direction of fishing's impact on parasite abundance is mediated by parasite traits, notably parasite transmission strategies.

    View details for Web of Science ID 000339470500021

    View details for PubMedID 25163125

  • Patterns and potential drivers of declining oxygen content along the southern California coast LIMNOLOGY AND OCEANOGRAPHY Booth, J. A., Woodson, C. B., Sutula, M., Micheli, F., Weisberg, S. B., Bograd, S. J., Steele, A., Schoen, J., Crowder, L. B. 2014; 59 (4): 1127-1138
  • A system-wide approach to supporting improvements in seafood production practices and outcomes FRONTIERS IN ECOLOGY AND THE ENVIRONMENT Micheli, F., De Leo, G., Shester, G. G., Martone, R. G., Lluch-Cota, S. E., Butner, C., Crowder, L. B., Fujita, R., Gelcich, S., Jams, M., Lester, S. E., McCay, B., Pelc, R., Saenz-Arroyo, A. 2014; 12 (5): 297-305

    View details for DOI 10.1890/110257

    View details for Web of Science ID 000336940100017

  • The effectiveness of coral reefs for coastal hazard risk reduction and adaptation NATURE COMMUNICATIONS Ferrario, F., Beck, M. W., Storlazzi, C. D., Micheli, F., Shepard, C. C., Airoldi, L. 2014; 5


    The world's coastal zones are experiencing rapid development and an increase in storms and flooding. These hazards put coastal communities at heightened risk, which may increase with habitat loss. Here we analyse globally the role and cost effectiveness of coral reefs in risk reduction. Meta-analyses reveal that coral reefs provide substantial protection against natural hazards by reducing wave energy by an average of 97%. Reef crests alone dissipate most of this energy (86%). There are 100 million or more people who may receive risk reduction benefits from reefs or bear hazard mitigation and adaptation costs if reefs are degraded. We show that coral reefs can provide comparable wave attenuation benefits to artificial defences such as breakwaters, and reef defences can be enhanced cost effectively. Reefs face growing threats yet there is opportunity to guide adaptation and hazard mitigation investments towards reef restoration to strengthen this first line of coastal defence.

    View details for DOI 10.1038/ncomms4794

    View details for Web of Science ID 000337372200005

    View details for PubMedID 24825660

  • Large-Scale Assessment of Mediterranean Marine Protected Areas Effects on Fish Assemblages PLOS ONE Guidetti, P., Baiata, P., Ballesteros, E., Di Franco, A., Hereu, B., Macpherson, E., Micheli, F., Pais, A., Panzalis, P., Rosenberg, A. A., Zabala, M., Sala, E. 2014; 9 (4)


    Marine protected areas (MPAs) were acknowledged globally as effective tools to mitigate the threats to oceans caused by fishing. Several studies assessed the effectiveness of individual MPAs in protecting fish assemblages, but regional assessments of multiple MPAs are scarce. Moreover, empirical evidence on the role of MPAs in contrasting the propagation of non-indigenous-species (NIS) and thermophilic species (ThS) is missing. We simultaneously investigated here the role of MPAs in reversing the effects of overfishing and in limiting the spread of NIS and ThS. The Mediterranean Sea was selected as study area as it is a region where 1) MPAs are numerous, 2) fishing has affected species and ecosystems, and 3) the arrival of NIS and the northward expansion of ThS took place. Fish surveys were done in well-enforced no-take MPAs (HP), partially-protected MPAs (IP) and fished areas (F) at 30 locations across the Mediterranean. Significantly higher fish biomass was found in HP compared to IP MPAs and F. Along a recovery trajectory from F to HP MPAs, IP were similar to F, showing that just well enforced MPAs triggers an effective recovery. Within HP MPAs, trophic structure of fish assemblages resembled a top-heavy biomass pyramid. Although the functional structure of fish assemblages was consistent among HP MPAs, species driving the recovery in HP MPAs differed among locations: this suggests that the recovery trajectories in HP MPAs are likely to be functionally similar (i.e., represented by predictable changes in trophic groups, especially fish predators), but the specific composition of the resulting assemblages may depend on local conditions. Our study did not show any effect of MPAs on NIS and ThS. These results may help provide more robust expectations, at proper regional scale, about the effects of new MPAs that may be established in the Mediterranean Sea and other ecoregions worldwide.

    View details for DOI 10.1371/journal.pone.0091841

    View details for Web of Science ID 000336863900008

    View details for PubMedID 24740479

  • High vulnerability of ecosystem function and services to diversity loss in Caribbean coral reefs BIOLOGICAL CONSERVATION Micheli, F., Mumby, P. J., Brumbaugh, D. R., Broad, K., Dahlgren, C. P., Harborne, A. R., Holmes, K. E., Kappel, C. V., Litvin, S. Y., Sanchirico, J. N. 2014; 171: 186-194
  • Cooperatives, concessions, and co-management on the Pacific coast of Mexico MARINE POLICY McCay, B. J., Micheli, F., Ponce-Diaz, G., Murray, G., Shester, G., Ramirez-Sanchez, S., Weisman, W. 2014; 44: 49-59
  • Cumulative Human Impacts on Mediterranean and Black Sea Marine Ecosystems: Assessing Current Pressures and Opportunities PLOS ONE Micheli, F., Halpern, B. S., Walbridge, S., Ciriaco, S., Ferretti, F., Fraschetti, S., Lewison, R., Nykjaer, L., Rosenberg, A. A. 2013; 8 (12)


    Management of marine ecosystems requires spatial information on current impacts. In several marine regions, including the Mediterranean and Black Sea, legal mandates and agreements to implement ecosystem-based management and spatial plans provide new opportunities to balance uses and protection of marine ecosystems. Analyses of the intensity and distribution of cumulative impacts of human activities directly connected to the ecological goals of these policy efforts are critically needed. Quantification and mapping of the cumulative impact of 22 drivers to 17 marine ecosystems reveals that 20% of the entire basin and 60-99% of the territorial waters of EU member states are heavily impacted, with high human impact occurring in all ecoregions and territorial waters. Less than 1% of these regions are relatively unaffected. This high impact results from multiple drivers, rather than one individual use or stressor, with climatic drivers (increasing temperature and UV, and acidification), demersal fishing, ship traffic, and, in coastal areas, pollution from land accounting for a majority of cumulative impacts. These results show that coordinated management of key areas and activities could significantly improve the condition of these marine ecosystems.

    View details for DOI 10.1371/journal.pone.0079889

    View details for Web of Science ID 000327949300012

    View details for PubMedID 24324585

  • Marine protected areas facilitate parasite populations among four fished host species of central Chile JOURNAL OF ANIMAL ECOLOGY Wood, C. L., Micheli, F., Fernandez, M., Gelcich, S., Carlos Castilla, J., Carvajal, J. 2013; 82 (6): 1276-1287


    Parasites comprise a substantial proportion of global biodiversity and exert important ecological influences on hosts, communities and ecosystems, but our knowledge of how parasite populations respond to human impacts is in its infancy. Here, we present the results of a natural experiment in which we used a system of highly successful marine protected areas and matched open-access areas in central Chile to assess the influence of fishing-driven biodiversity loss on parasites of exploited fish and invertebrate hosts. We measured the burden of gill parasites for two reef fishes (Cheilodactylus variegatus and Aplodactylus punctatus), trematode parasites for a keyhole limpet (Fissurella latimarginata), and pinnotherid pea crab parasites for a sea urchin (Loxechinus albus). We also measured host density for all four hosts. We found that nearly all parasite species exhibited substantially greater density (# parasites m(-2) ) in protected than in open-access areas, but only one parasite species (a gill monogenean of C. variegatus) was more abundant within hosts collected from protected relative to open-access areas. These data indicate that fishing can drive declines in parasite abundance at the parasite population level by reducing the availability of habitat and resources for parasites, but less commonly affects the abundance of parasites at the infrapopulation level (within individual hosts). Considering the substantial ecological role that many parasites play in marine communities, fishing and other human impacts could exert cryptic but important effects on marine community structure and ecosystem functioning via reductions in parasite abundance.

    View details for DOI 10.1111/1365-2656.12104

    View details for Web of Science ID 000326036800017

  • Conservation at the edges of the world BIOLOGICAL CONSERVATION McCauley, D. J., Power, E. A., Bird, D. W., McInturff, A., Dunbar, R. B., Durham, W. H., Micheli, F., Young, H. S. 2013; 165: 139-145
  • Linking human activity and ecosystem condition to inform marine ecosystem based management AQUATIC CONSERVATION-MARINE AND FRESHWATER ECOSYSTEMS Menzel, S., Kappel, C. V., Broitman, B. R., Micheli, F., Rosenberg, A. A. 2013; 23 (4): 506-514

    View details for DOI 10.1002/aqc.2365

    View details for Web of Science ID 000321821300005

  • Community dynamics and ecosystem simplification in a high-CO2 ocean PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA Kroeker, K. J., Gambi, M. C., Micheli, F. 2013; 110 (31): 12721-12726


    Disturbances are natural features of ecosystems that promote variability in the community and ultimately maintain diversity. Although it is recognized that global change will affect environmental disturbance regimes, our understanding of the community dynamics governing ecosystem recovery and the maintenance of functional diversity in future scenarios is very limited. Here, we use one of the few ecosystems naturally exposed to future scenarios of environmental change to examine disturbance and recovery dynamics. We examine the recovery patterns of marine species from a physical disturbance across different acidification regimes caused by volcanic CO2 vents. Plots of shallow rocky reef were cleared of all species in areas of ambient, low, and extreme low pH that correspond to near-future and extreme scenarios for ocean acidification. Our results illustrate how acidification decreases the variability of communities, resulting in homogenization and reduced functional diversity at a landscape scale. Whereas the recovery trajectories in ambient pH were highly variable and resulted in a diverse range of assemblages, recovery was more predictable with acidification and consistently resulted in very similar algal-dominated assemblages. Furthermore, low pH zones had fewer signs of biological disturbance (primarily sea urchin grazing) and increased recovery rates of the dominant taxa (primarily fleshy algae). Together, our results highlight how environmental change can cause ecosystem simplification via environmentally mediated changes in community dynamics in the near future, with cascading impacts on functional diversity and ecosystem function.

    View details for DOI 10.1073/pnas.1216464110

    View details for Web of Science ID 000322441500055

    View details for PubMedID 23836638

  • Ecomarkets for conservation and sustainable development in the coastal zone BIOLOGICAL REVIEWS Fujita, R., Lynham, J., Micheli, F., Feinberg, P. G., Bourillon, L., Saenz-Arroyo, A., Markham, A. C. 2013; 88 (2): 273-286


    Because conventional markets value only certain goods or services in the ocean (e.g. fish), other services provided by coastal and marine ecosystems that are not priced, paid for, or stewarded tend to become degraded. In fact, the very capacity of an ecosystem to produce a valued good or service is often reduced because conventional markets value only certain goods and services, rather than the productive capacity. Coastal socio-ecosystems are particularly susceptible to these market failures due to the lack of clear property rights, strong dependence on resource extraction, and other factors. Conservation strategies aimed at protecting unvalued coastal ecosystem services through regulation or spatial management (e.g. Marine Protected Areas) can be effective but often result in lost revenue and adverse social impacts, which, in turn, create conflict and opposition. Here, we describe 'ecomarkets' - markets and financial tools - that could, under the right conditions, generate value for broad portfolios of coastal ecosystem services while maintaining ecosystem structure and function by addressing the unique problems of the coastal zone, including the lack of clear management and exclusion rights. Just as coastal tenure and catch-share systems generate meaningful conservation and economic outcomes, it is possible to imagine other market mechanisms that do the same with respect to a variety of other coastal ecosystem goods and services. Rather than solely relying on extracting goods, these approaches could allow communities to diversify ecosystem uses and focus on long-term stewardship and conservation, while meeting development, food security, and human welfare goals. The creation of ecomarkets will be difficult in many cases, because rights and responsibilities must be devolved, new social contracts will be required, accountability systems must be created and enforced, and long-term patterns of behaviour must change. We argue that efforts to overcome these obstacles are justified, because these deep changes will strongly complement policies and tools such as Marine Protected Areas, coastal spatial management, and regulation, thereby helping to bring coastal conservation to scale.

    View details for DOI 10.1111/j.1469-185X.2012.00251.x

    View details for Web of Science ID 000317067900002

    View details for PubMedID 23176665

  • Decreased solar radiation and increased temperature combine to facilitate fouling by marine non-indigenous species BIOFOULING Kim, T. W., Micheli, F. 2013; 29 (5): 501-512


    Studies of the effects of climate changes on marine biofouling have mainly focused on the effects of temperature increase, but a decrease in the level of solar radiation could also influence the establishment and persistence of fouling species. To test if decreased solar radiation and/or increased temperature influenced marine fouling communities, solar radiation, and temperature were manipulated by deploying shading devices in the intertidal zone of a central California estuary. Non-indigenous species (NIS) recruiting to artificial substrata had greater coverage under the shading treatments than under transparent plates, indicating that low radiation facilitates recruitment and growth of NIS. In contrast, the coverage of NIS underneath warmer black plates was higher than that on white plates. Furthermore, spatial comparisons of recruitment showed that NIS had a tendency to grow better in the warmer region of the estuary whereas native species showed the opposing trend. The results suggest that both lower radiation and higher temperature may facilitate the spread of marine NIS.

    View details for DOI 10.1080/08927014.2013.784964

    View details for Web of Science ID 000319740800003

    View details for PubMedID 23668309

  • Dispersal at a snail's pace: historical processes affect contemporary genetic structure in the exploited wavy top snail (Megastraea undosa). journal of heredity Haupt, A. J., Micheli, F., Palumbi, S. R. 2013; 104 (3): 327-340


    We used population genetics to assess historical and modern demography of the exploited wavy top snail, Megastraea undosa, which has a 5-10 day pelagic larval duration. Foot tissue was sampled from an average of 51 individuals at 17 sites across the range of M. undosa. Genetic structure at the mtDNA locus is strikingly high (ΦST of 0.19 across 1000 km), and a major cline occurs in northern Baja California (ΦCT of 0.29 between northern and southern populations). Genetic data indicate that the northern region is highly connected through larval dispersal, whereas the southern region exhibits low genetic structure. However, additional analyses based on patterns of haplotype diversity and relationships among haplotypes indicate that M. undosa has likely recently expanded into the Southern California Bight or expanded from a small refugial population, and analysis using isolation by distance to calculate dispersal distance indicates surprisingly short estimates of dispersal from 30 m to 3 km. This scenario of a northward expansion and limited larval dispersal is supported by coalescent-based simulations of genetic data. The different patterns of genetic variation between northern and southern populations are likely artifacts of evolutionary history rather than differences in larval dispersal and this may have applications to management of this species. Specifically, these data can help to inform the scale at which this species should be managed, and given the potentially very small dispersal distances, this species should be managed at local scales. Consideration of the evolutionary history of target species allows for a more accurate interpretation of genetic data for management.

    View details for DOI 10.1093/jhered/est002

    View details for PubMedID 23450089

  • Setting Priorities for Regional Conservation Planning in the Mediterranean Sea PLOS ONE Micheli, F., Levin, N., Giakoumi, S., Katsanevakis, S., Abdulla, A., Coll, M., Fraschetti, S., Kark, S., Koutsoubas, D., Mackelworth, P., Maiorano, L., Possingham, H. P. 2013; 8 (4)


    Spatial prioritization in conservation is required to direct limited resources to where actions are most urgently needed and most likely to produce effective conservation outcomes. In an effort to advance the protection of a highly threatened hotspot of marine biodiversity, the Mediterranean Sea, multiple spatial conservation plans have been developed in recent years. Here, we review and integrate these different plans with the goal of identifying priority conservation areas that represent the current consensus among the different initiatives. A review of six existing and twelve proposed conservation initiatives highlights gaps in conservation and management planning, particularly within the southern and eastern regions of the Mediterranean and for offshore and deep sea habitats. The eighteen initiatives vary substantially in their extent (covering 0.1-58.5% of the Mediterranean Sea) and in the location of additional proposed conservation and management areas. Differences in the criteria, approaches and data used explain such variation. Despite the diversity among proposals, our analyses identified ten areas, encompassing 10% of the Mediterranean Sea, that are consistently identified among the existing proposals, with an additional 10% selected by at least five proposals. These areas represent top priorities for immediate conservation action. Despite the plethora of initiatives, major challenges face Mediterranean biodiversity and conservation. These include the need for spatial prioritization within a comprehensive framework for regional conservation planning, the acquisition of additional information from data-poor areas, species or habitats, and addressing the challenges of establishing transboundary governance and collaboration in socially, culturally and politically complex conditions. Collective prioritised action, not new conservation plans, is needed for the north, western, and high seas of the Mediterranean, while developing initial information-based plans for the south and eastern Mediterranean is an urgent requirement for true regional conservation planning.

    View details for DOI 10.1371/journal.pone.0059038

    View details for Web of Science ID 000319109800006

    View details for PubMedID 23577060

  • REPRODUCTIVE POTENTIAL CAN PREDICT RECRUITMENT RATES IN ABALONE JOURNAL OF SHELLFISH RESEARCH Rossetto, M., De Leo, G. A., Greenley, A., Vazquez, L., Saenz-Arroyo, A., Espinoza Montes, J. A., Micheli, F. 2013; 32 (1): 161-169
  • Ocean acidification causes ecosystem shifts via altered competitive interactions NATURE CLIMATE CHANGE Kroeker, K. J., Micheli, F., Gambi, M. C. 2013; 3 (2): 156-159
  • Linking human activity and ecosystem condition to inform ecosystem-based management Aquatic Conservation: Marine and Freshwater Ecosystems Menzel, S., Kappel, C., Broitman, B., Micheli, F., Rosenberg, A. 2013

    View details for DOI 10.1002/aqc.2365

  • Conserving Biodiversity in a Human-Dominated World: Degradation of Marine Sessile Communities within a Protected Area with Conflicting Human Uses. PloS one Parravicini, V., Micheli, F., Montefalcone, M., Morri, C., Villa, E., Castellano, M., Povero, P., Bianchi, C. N. 2013; 8 (10)


    Conservation research aims at understanding whether present protection schemes are adequate for the maintenance of ecosystems structure and function across time. We evaluated long-term variation in rocky reef communities by comparing sites surveyed in 1993 and again in 2008. This research took place in Tigullio Gulf, an emblematic case study where various conservation measures, including a marine protected area, have been implemented to manage multiple human uses. Contrary to our prediction that protection should have favored ecosystem stability, we found that communities subjected to conservation measures (especially within the marine protected area) exhibited the greatest variation toward architectural complexity loss. Between 1993 and 2008, chronic anthropogenic pressures (especially organic load) that had already altered unprotected sites in 1993 expanded their influence into protected areas. This expansion of human pressure likely explains our observed changes in the benthic communities. Our results suggest that adaptive ecosystem-based management (EBM), that is management taking into account human interactions, informed by continuous monitoring, is needed in order to attempt reversing the current trend towards less architecturally complex communities. Protected areas are not sufficient to stop ecosystem alteration by pressures coming from outside. Monitoring, and consequent management actions, should therefore extend to cover the relevant scales of those pressures.

    View details for DOI 10.1371/journal.pone.0075767

    View details for PubMedID 24143173

  • Conservation at the edges of the world Biological Conservation McCauley, D., Power, E., Bird, D., Dunbar, R., Durham, W., Micheli, F., Young, H. 2013; 165: 139-145
  • Reproductive potential predicts recruitment rates in abalones J Shellfish Res Rossetto, M., De Leo, G., Saenz, A., Greenley, A., Vazquez, L., Espinoza, A., Micheli, F. 2013; 32: 161-169
  • Advancing marine conservation planning in the Mediterranean Sea REVIEWS IN FISH BIOLOGY AND FISHERIES Giakoumi, S., Mazor, T., Fraschetti, S., Kark, S., Portman, M., Coll, M., Steenbeek, J., Possingham, H. 2012; 22 (4): 943-949
  • Stable Isotope Analysis Challenges Wasp-Waist Food Web Assumptions in an Upwelling Pelagic Ecosystem SCIENTIFIC REPORTS Madigan, D. J., Carlisle, A. B., Dewar, H., Snodgrass, O. E., Litvin, S. Y., Micheli, F., Block, B. A. 2012; 2


    Eastern boundary currents are often described as 'wasp-waist' ecosystems in which one or few mid-level forage species support a high diversity of larger predators that are highly susceptible to fluctuations in prey biomass. The assumption of wasp-waist control has not been empirically tested in all such ecosystems. This study used stable isotope analysis to test the hypothesis of wasp-waist control in the southern California Current large marine ecosystem (CCLME). We analyzed prey and predator tissue for ?¹³C and ?¹?N and used Bayesian mixing models to provide estimates of CCLME trophic dynamics from 2007-2010. Our results show high omnivory, planktivory by some predators, and a higher degree of trophic connectivity than that suggested by the wasp-waist model. Based on this study period, wasp-waist models oversimplify trophic dynamics within the CCLME and potentially other upwelling, pelagic ecosystems. Higher trophic connectivity in the CCLME likely increases ecosystem stability and resilience to perturbations.

    View details for DOI 10.1038/srep00654

    View details for Web of Science ID 000308807000002

    View details for PubMedID 22977729

  • Assessing the effects of large mobile predators on ecosystem connectivity ECOLOGICAL APPLICATIONS McCauley, D. J., Young, H. S., Dunbar, R. B., Estes, J. A., Semmens, B. X., Michel, F. 2012; 22 (6): 1711-1717


    Large predators are often highly mobile and can traverse and use multiple habitats. We know surprisingly little about how predator mobility determines important processes of ecosystem connectivity. Here we used a variety of data sources drawn from Palmyra Atoll, a remote tropical marine ecosystem where large predators remain in high abundance, to investigate how these animals foster connectivity. Our results indicate that three of Palmyra's most abundant large predators (e.g., two reef sharks and one snapper) use resources from different habitats creating important linkages across ecosystems. Observations of cross-system foraging such as this have important implications for the understanding of ecosystem functioning, the management of large-predator populations, and the design of conservation measures intended to protect whole ecosystems. In the face of widespread declines of large, mobile predators, it is important that resource managers, policy makers, and ecologists work to understand how these predators create connectivity and to determine the impact that their depletions may be having on the integrity of these linkages.

    View details for Web of Science ID 000309437100001

  • Understanding relationships between conflicting human uses and coastal ecosystems status: A geospatial modeling approach ECOLOGICAL INDICATORS Parravicini, V., Rovere, A., Vassallo, P., Micheli, F., Montefalcone, M., Morri, C., Paoli, C., Albertelli, G., Fabiano, M., Bianchi, C. N. 2012; 19: 253-263
  • Evidence That Marine Reserves Enhance Resilience to Climatic Impacts PLOS ONE Micheli, F., Saenz-Arroyo, A., Greenley, A., Vazquez, L., Espinoza Montes, J. A., Rossetto, M., De Leo, G. A. 2012; 7 (7)


    Establishment of marine protected areas, including fully protected marine reserves, is one of the few management tools available for local communities to combat the deleterious effect of large scale environmental impacts, including global climate change, on ocean ecosystems. Despite the common hope that reserves play this role, empirical evidence of the effectiveness of local protection against global problems is lacking. Here we show that marine reserves increase the resilience of marine populations to a mass mortality event possibly caused by climate-driven hypoxia. Despite high and widespread adult mortality of benthic invertebrates in Baja California, Mexico, that affected populations both within and outside marine reserves, juvenile replenishment of the species that supports local economies, the pink abalone Haliotis corrugata, remained stable within reserves because of large body size and high egg production of the protected adults. Thus, local protection provided resilience through greater resistance and faster recovery of protected populations. Moreover, this benefit extended to adjacent unprotected areas through larval spillover across the edges of the reserves. While climate change mitigation is being debated, coastal communities have few tools to slow down negative impacts of global environmental shifts. These results show that marine protected areas can provide such protection.

    View details for DOI 10.1371/journal.pone.0040832

    View details for Web of Science ID 000306548900054

    View details for PubMedID 22855690

  • Night Shift: Expansion of Temporal Niche Use Following Reductions in Predator Density PLOS ONE McCauley, D. J., Hoffmann, E., Young, H. S., Micheli, F. 2012; 7 (6)


    Predation shapes many fundamental aspects of ecology. Uncertainty remains, however, about whether predators can influence patterns of temporal niche construction at ecologically relevant timescales. Partitioning of time is an important mechanism by which prey avoid interactions with predators. However, the traits that control a prey organism's capacity to operate during a particular portion of the diel cycle are diverse and complex. Thus, diel prey niches are often assumed to be relatively unlikely to respond to changes in predation risk at short timescales. Here we present evidence to the contrary. We report results that suggest that the anthropogenic depletion of daytime active predators (species that are either diurnal or cathemeral) in a coral reef ecosystem is associated with rapid temporal niche expansions in a multi-species assemblage of nocturnal prey fishes. Diurnal comparisons of nocturnal prey fish abundance in predator rich and predator depleted reefs at two atolls revealed that nocturnal fish were approximately six (biomass) and eight (density) times more common during the day on predator depleted reefs. Amongst these, the prey species that likely were the most specialized for nocturnal living, and thus the most vulnerable to predation (i.e. those with greatest eye size to body length ratio), showed the strongest diurnal increases at sites where daytime active predators were rare. While we were unable to determine whether these observed increases in diurnal abundance by nocturnal prey were the result of a numerical or behavioral response, either effect could be ecologically significant. These results raise the possibility that predation may play an important role in regulating the partitioning of time by prey and that anthropogenic depletions of predators may be capable of causing rapid changes to key properties of temporal community architecture.

    View details for DOI 10.1371/journal.pone.0038871

    View details for Web of Science ID 000305341900058

    View details for PubMedID 22719970

  • New tetranucleotide microsatellite loci in pink abalone (Haliotis corrugata) isolated via 454 pyrosequencing CONSERVATION GENETICS RESOURCES Greenley, A. P., Muguia-Vega, A., Saenz-Arroyo, A., Micheli, F. 2012; 4 (2): 265-268
  • From wing to wing: the persistence of long ecological interaction chains in less-disturbed ecosystems SCIENTIFIC REPORTS McCauley, D. J., DeSalles, P. A., Young, H. S., Dunbar, R. B., Dirzo, R., Mills, M. M., Micheli, F. 2012; 2


    Human impact on biodiversity usually is measured by reduction in species abundance or richness. Just as important, but much more difficult to discern, is the anthropogenic elimination of ecological interactions. Here we report on the persistence of a long ecological interaction chain linking diverse food webs and habitats in the near-pristine portions of a remote Pacific atoll. Using biogeochemical assays, animal tracking, and field surveys we show that seabirds roosting on native trees fertilize soils, increasing coastal nutrients and the abundance of plankton, thus attracting manta rays to native forest coastlines. Partnered observations conducted in regions of this atoll where native trees have been replaced by human propagated palms reveal that this complex interaction chain linking trees to mantas readily breaks down. Taken together these findings provide a compelling example of how anthropogenic disturbance may be contributing to widespread reductions in ecological interaction chain length, thereby isolating and simplifying ecosystems.

    View details for DOI 10.1038/srep00409

    View details for Web of Science ID 000304393800001

    View details for PubMedID 22624091

  • Allometric scaling of mortality rates with body mass in abalones OECOLOGIA Rossetto, M., De Leo, G. A., Bevacqua, D., Micheli, F. 2012; 168 (4): 989-996


    The existence of an allometric relationship between mortality rates and body mass has been theorized and extensively documented across taxa. Within species, however, the allometry between mortality rates and body mass has received substantially less attention and the consistency of such scaling patterns at the intra-specific level is controversial. We reviewed 73 experimental studies to examine the relationship between mortality rates and body size among seven species of abalone (Haliotis spp.), a marine herbivorous mollusk. Both in the field and in the laboratory, log-transformed mortality rates were negatively correlated with log-transformed individual body mass for all species considered, with allometric exponents remarkably similar among species. This regular pattern confirms previous findings that juvenile abalones suffer higher mortality rates than adult individuals. Field mortality rates were higher overall than those measured in the laboratory, and the relationship between mortality and body mass tended to be steeper in field than in laboratory conditions for all species considered. These results suggest that in the natural environment, additional mortality factors, especially linked to predation, could significantly contribute to mortality, particularly at small body sizes. On the other hand, the consistent allometry of mortality rates versus body mass in laboratory conditions suggests that other sources of mortality, beside predation, are size-dependent in abalone.

    View details for DOI 10.1007/s00442-011-2163-1

    View details for Web of Science ID 000301604200010

    View details for PubMedID 22020817

  • Evaluating the performance of methods for estimating the abundance of rapidly declining coastal shark populations ECOLOGICAL APPLICATIONS McCauley, D. J., Mclean, K. A., Bauer, J., Young, H. S., Micheli, F. 2012; 22 (2): 385-392


    Accurately surveying shark populations is critical to monitoring precipitous ongoing declines in shark abundance and interpreting the effects that these reductions are having on ecosystems. To evaluate the effectiveness of existing survey tools, we used field trials and computer simulations to critically examine the operation of four common methods for counting coastal sharks: stationary point counts, belt transects, video surveys, and mark and recapture abundance estimators. Empirical and theoretical results suggest that (1) survey method selection has a strong impact on the estimates of shark density that are produced, (2) standardizations by survey duration are needed to properly interpret and compare survey outputs, (3) increasing survey size does not necessarily increase survey precision, and (4) methods that yield the highest density estimates are not always the most accurate. These findings challenge some of the assumptions traditionally associated with surveying mobile marine animals. Of the methods we trialed, 8 x 50 m belt transects and a 20 m radius point count produced the most accurate estimates of shark density. These findings can help to improve the ways we monitor, manage, and understand the ecology of globally imperiled coastal shark populations.

    View details for Web of Science ID 000302516900001

    View details for PubMedID 22611841

  • The Structure of Mediterranean Rocky Reef Ecosystems across Environmental and Human Gradients, and Conservation Implications PLOS ONE Sala, E., Ballesteros, E., Dendrinos, P., Di Franco, A., Ferretti, F., Foley, D., Fraschetti, S., Friedlander, A., Garrabou, J., Guclusoy, H., Guidetti, P., Halpern, B. S., Hereu, B., Karamanlidis, A. A., Kizilkaya, Z., Macpherson, E., Mangialajo, L., Mariani, S., Micheli, F., Pais, A., Riser, K., Rosenberg, A. A., Sales, M., Selkoe, K. A., Starr, R., Tomas, F., Zabala, M. 2012; 7 (2)


    Historical exploitation of the Mediterranean Sea and the absence of rigorous baselines makes it difficult to evaluate the current health of the marine ecosystems and the efficacy of conservation actions at the ecosystem level. Here we establish the first current baseline and gradient of ecosystem structure of nearshore rocky reefs at the Mediterranean scale. We conducted underwater surveys in 14 marine protected areas and 18 open access sites across the Mediterranean, and across a 31-fold range of fish biomass (from 3.8 to 118 g m(-2)). Our data showed remarkable variation in the structure of rocky reef ecosystems. Multivariate analysis showed three alternative community states: (1) large fish biomass and reefs dominated by non-canopy algae, (2) lower fish biomass but abundant native algal canopies and suspension feeders, and (3) low fish biomass and extensive barrens, with areas covered by turf algae. Our results suggest that the healthiest shallow rocky reef ecosystems in the Mediterranean have both large fish and algal biomass. Protection level and primary production were the only variables significantly correlated to community biomass structure. Fish biomass was significantly larger in well-enforced no-take marine reserves, but there were no significant differences between multi-use marine protected areas (which allow some fishing) and open access areas at the regional scale. The gradients reported here represent a trajectory of degradation that can be used to assess the health of any similar habitat in the Mediterranean, and to evaluate the efficacy of marine protected areas.

    View details for DOI 10.1371/journal.pone.0032742

    View details for Web of Science ID 000303003500099

    View details for PubMedID 22393445

  • Geographic variation in demography of a temperate reef snail: importance of multiple life-history traits MARINE ECOLOGY PROGRESS SERIES Martone, R. G., Micheli, F. 2012; 457: 85-99

    View details for DOI 10.3354/meps09693

    View details for Web of Science ID 000306755000007

  • High-Frequency Dynamics of Ocean pH: A Multi-Ecosystem Comparison PLOS ONE Hofmann, G. E., Smith, J. E., Johnson, K. S., Send, U., Levin, L. A., Micheli, F., Paytan, A., Price, N. N., Peterson, B., Takeshita, Y., Matson, P. G., Crook, E. D., Kroeker, K. J., Gambi, M. C., Rivest, E. B., Frieder, C. A., Yu, P. C., Martz, T. R. 2011; 6 (12)


    The effect of Ocean Acidification (OA) on marine biota is quasi-predictable at best. While perturbation studies, in the form of incubations under elevated pCO(2), reveal sensitivities and responses of individual species, one missing link in the OA story results from a chronic lack of pH data specific to a given species' natural habitat. Here, we present a compilation of continuous, high-resolution time series of upper ocean pH, collected using autonomous sensors, over a variety of ecosystems ranging from polar to tropical, open-ocean to coastal, kelp forest to coral reef. These observations reveal a continuum of month-long pH variability with standard deviations from 0.004 to 0.277 and ranges spanning 0.024 to 1.430 pH units. The nature of the observed variability was also highly site-dependent, with characteristic diel, semi-diurnal, and stochastic patterns of varying amplitudes. These biome-specific pH signatures disclose current levels of exposure to both high and low dissolved CO(2), often demonstrating that resident organisms are already experiencing pH regimes that are not predicted until 2100. Our data provide a first step toward crystallizing the biophysical link between environmental history of pH exposure and physiological resilience of marine organisms to fluctuations in seawater CO(2). Knowledge of this spatial and temporal variation in seawater chemistry allows us to improve the design of OA experiments: we can test organisms with a priori expectations of their tolerance guardrails, based on their natural range of exposure. Such hypothesis-testing will provide a deeper understanding of the effects of OA. Both intuitively simple to understand and powerfully informative, these and similar comparative time series can help guide management efforts to identify areas of marine habitat that can serve as refugia to acidification as well as areas that are particularly vulnerable to future ocean change.

    View details for DOI 10.1371/journal.pone.0028983

    View details for Web of Science ID 000298665600019

    View details for PubMedID 22205986

  • Ancient art serving marine conservation FRONTIERS IN ECOLOGY AND THE ENVIRONMENT Guidetti, P., Micheli, F. 2011; 9 (7): 374-375

    View details for DOI 10.1890/11.WB.019

    View details for Web of Science ID 000294978500012

  • Divergent ecosystem responses within a benthic marine community to ocean acidification PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA Kroeker, K. J., Micheli, F., Gambi, M. C., Martz, T. R. 2011; 108 (35): 14515-14520


    Ocean acidification is predicted to impact all areas of the oceans and affect a diversity of marine organisms. However, the diversity of responses among species prevents clear predictions about the impact of acidification at the ecosystem level. Here, we used shallow water CO(2) vents in the Mediterranean Sea as a model system to examine emergent ecosystem responses to ocean acidification in rocky reef communities. We assessed in situ benthic invertebrate communities in three distinct pH zones (ambient, low, and extreme low), which differed in both the mean and variability of seawater pH along a continuous gradient. We found fewer taxa, reduced taxonomic evenness, and lower biomass in the extreme low pH zones. However, the number of individuals did not differ among pH zones, suggesting that there is density compensation through population blooms of small acidification-tolerant taxa. Furthermore, the trophic structure of the invertebrate community shifted to fewer trophic groups and dominance by generalists in extreme low pH, suggesting that there may be a simplification of food webs with ocean acidification. Despite high variation in individual species' responses, our findings indicate that ocean acidification decreases the diversity, biomass, and trophic complexity of benthic marine communities. These results suggest that a loss of biodiversity and ecosystem function is expected under extreme acidification scenarios.

    View details for DOI 10.1073/pnas.1107789108

    View details for Web of Science ID 000294425900034

    View details for PubMedID 21844331

  • Conservation challenges for small-scale fisheries: Bycatch and habitat impacts of traps and gillnets BIOLOGICAL CONSERVATION Shester, G. G., Micheli, F. 2011; 144 (5): 1673-1681
  • Acute effects of removing large fish from a near-pristine coral reef MARINE BIOLOGY McCauley, D. J., Micheli, F., Young, H. S., Tittensor, D. P., Brumbaugh, D. R., Madin, E. M., Holmes, K. E., Smith, J. E., Lotze, H. K., DeSalles, P. A., Arnold, S. N., Worm, B. 2010; 157 (12): 2739-2750
  • Rapid assessment of epibenthic communities: A comparison between two visual sampling techniques JOURNAL OF EXPERIMENTAL MARINE BIOLOGY AND ECOLOGY Parravicini, V., Micheli, F., Montefalcone, M., Villa, E., Morri, C., Bianchi, C. N. 2010; 395 (1-2): 21-29
  • The value of spatial information in MPA network design PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA Costello, C., Rassweiler, A., Siegel, D., De Leo, G., Micheli, F., Rosenberg, A. 2010; 107 (43): 18294-18299


    The science of spatial fisheries management, which combines ecology, oceanography, and economics, has matured significantly. As a result, there have been recent advances in exploiting spatially explicit data to develop spatially explicit management policies, such as networks of marine protected areas (MPAs). However, when data are sparse, spatially explicit policies become less viable, and we must instead rely on blunt policies such as total allowable catches or imprecisely configured networks of MPAs. Therefore, spatial information has the potential to change management approaches and thus has value. We develop a general framework within which to analyze the value of information for spatial fisheries management and apply that framework to several US Pacific coast fisheries. We find that improved spatial information can increase fishery value significantly (>10% in our simulations), and that it changes dramatically the efficient management approach-switching from diffuse effort everywhere to a strategy where fishing is spatially targeted, with some areas under intensive harvest and others closed to fishing. Using all available information, even when incomplete, is essential to management success and may as much as double fishery value relative to using (admittedly incorrect) assumptions commonly invoked.

    View details for DOI 10.1073/pnas.0908057107

    View details for Web of Science ID 000283677400016

    View details for PubMedID 20176962

  • Disentangling trophic interactions inside a Caribbean marine reserve ECOLOGICAL APPLICATIONS Kellner, J. B., Litvin, S. Y., Hastings, A., Micheli, F., Mumby, P. J. 2010; 20 (7): 1979-1992


    Recent empirical studies have demonstrated that human activities such as fishing can strongly affect the natural capital and services provided by tropical seascapes. However, policies to mitigate anthropogenic impacts can also alter food web structure and interactions, regardless of whether the regulations are aimed at single or multiple species, with possible unexpected consequences for the ecosystems and their associated services. Complex community response to management interventions have been highlighted in the Caribbean, where, contrary to predictions from linear food chain models, a reduction in fishing intensity through the establishment of a marine reserve has led to greater biomass of herbivorous fish inside the reserve, despite an increased abundance of large predatory piscivores. This positive multi-trophic response, where both predators and prey benefit from protection, highlights the need to take an integrated approach that considers how numerous factors control species coexistence in both fished and unfished systems. In order to understand these complex relationships, we developed a general model to examine the trade-offs between fishing pressure and trophic control on reef fish communities, including an exploration of top-down and bottom-up effects. We then validated the general model predictions by parameterizing the model for a reef system in the Bahamas in order to tease apart the wide range of species responses to reserves in the Caribbean. Combining the development of general theory and site-specific models parameterized with field data reveals the underlying driving forces in these communities and enables us to make better predictions about possible population and community responses to different management schemes.

    View details for Web of Science ID 000282278200017

    View details for PubMedID 21049884

  • Guiding ecological principles for marine spatial planning MARINE POLICY Foley, M. M., Halpern, B. S., Micheli, F., Armsby, M. H., Caldwell, M. R., Crain, C. M., Prahler, E., Rohr, N., Sivas, D., Beck, M. W., Carr, M. H., Crowder, L. B., Duffy, J. E., Hacker, S. D., McLeod, K. L., Palumbi, S. R., Peterson, C. H., Regan, H. M., Ruckelshaus, M. H., Sandifer, P. A., Steneck, R. S. 2010; 34 (5): 955-966
  • Non-native Ecosystem Engineer Alters Estuarine Communities INTEGRATIVE AND COMPARATIVE BIOLOGY Heiman, K. W., Micheli, F. 2010; 50 (2): 226-236


    Many ecosystems are created by the presence of ecosystem engineers that play an important role in determining species' abundance and species composition. Additionally, a mosaic environment of engineered and non-engineered habitats has been shown to increase biodiversity. Non-native ecosystem engineers can be introduced into environments that do not contain or have lost species that form biogenic habitat, resulting in dramatic impacts upon native communities. Yet, little is known about how non-native ecosystem engineers interact with natives and other non-natives already present in the environment, specifically whether non-native ecosystem engineers facilitate other non-natives, and whether they increase habitat heterogeneity and alter the diversity, abundance, and distribution of benthic species. Through sampling and experimental removal of reefs, we examine the effects of a non-native reef-building tubeworm, Ficopomatus enigmaticus, on community composition in the central Californian estuary, Elkhorn Slough. Tubeworm reefs host significantly greater abundances of many non-native polychaetes and amphipods, particularly the amphipods Monocorophium insidiosum and Melita nitida, compared to nearby mudflats. Infaunal assemblages under F. enigmaticus reefs and around reef's edges show very low abundance and taxonomic diversity. Once reefs are removed, the newly exposed mudflat is colonized by opportunistic non-native species, such as M. insidiosum and the polychaete Streblospio benedicti, making removal of reefs a questionable strategy for control. These results show that provision of habitat by a non-native ecosystem engineer may be a mechanism for invasional meltdown in Elkhorn Slough, and that reefs increase spatial heterogeneity in the abundance and composition of benthic communities.

    View details for DOI 10.1093/icb/icq036

    View details for Web of Science ID 000280279800007

    View details for PubMedID 21558201

  • Using expert judgment to estimate marine ecosystem vulnerability in the California Current ECOLOGICAL APPLICATIONS Teck, S. J., Halpern, B. S., Kappel, C. V., Micheli, F., Selkoe, K. A., Crain, C. M., Martone, R., Shearer, C., Arvai, J., Fischhoff, B., Murray, G., Neslo, R., Cooke, R. 2010; 20 (5): 1402-1416


    As resource management and conservation efforts move toward multi-sector, ecosystem-based approaches, we need methods for comparing the varying responses of ecosystems to the impacts of human activities in order to prioritize management efforts, allocate limited resources, and understand cumulative effects. Given the number and variety of human activities affecting ecosystems, relatively few empirical studies are adequately comprehensive to inform these decisions. Consequently, management often turns to expert judgment for information. Drawing on methods from decision science, we offer a method for eliciting expert judgment to (1) quantitatively estimate the relative vulnerability of ecosystems to stressors, (2) help prioritize the management of stressors across multiple ecosystems, (3) evaluate how experts give weight to different criteria to characterize vulnerability of ecosystems to anthropogenic stressors, and (4) identify key knowledge gaps. We applied this method to the California Current region in order to evaluate the relative vulnerability of 19 marine ecosystems to 53 stressors associated with human activities, based on surveys from 107 experts. When judging the relative vulnerability of ecosystems to stressors, we found that experts primarily considered two criteria: the ecosystem's resistance to the stressor and the number of species or trophic levels affected. Four intertidal ecosystems (mudflat, beach, salt marsh, and rocky intertidal) were judged most vulnerable to the suite of human activities evaluated here. The highest vulnerability rankings for coastal ecosystems were invasive species, ocean acidification, sea temperature change, sea level rise, and habitat alteration from coastal engineering, while offshore ecosystems were assessed to be most vulnerable to ocean acidification, demersal destructive fishing, and shipwrecks. These results provide a quantitative, transparent, and repeatable assessment of relative vulnerability across ecosystems to any ongoing or emerging human activity. Combining these results with data on the spatial distribution and intensity of human activities provides a systematic foundation for ecosystem-based management.

    View details for Web of Science ID 000279047400015

    View details for PubMedID 20666257

  • Fishing out marine parasites? Impacts of fishing on rates of parasitism in the ocean ECOLOGY LETTERS Wood, C. L., Lafferty, K. D., Micheli, F. 2010; 13 (6): 761-775


    Among anthropogenic effects on the ocean, fishing is one of the most pervasive and extends deepest into the past. Because fishing reduces the density of fish (reducing transmission efficiency of directly transmitted parasites), selectively removes large fish (which tend to carry more parasites than small fish), and reduces food web complexity (reducing transmission efficiency of trophically transmitted parasites), the removal of fish from the world's oceans over the course of hundreds of years may be driving a longterm, global decline in fish parasites. There has been growing recognition in recent years that parasites are a critical part of biodiversity and that their loss could substantially alter ecosystem function. Such a loss may be among the last major ecological effects of industrial fishing to be recognized by scientists.

    View details for DOI 10.1111/j.1461-0248.2010.01467.x

    View details for Web of Science ID 000277867100011

    View details for PubMedID 20412277

  • Global priority areas for incorporating land-sea connections in marine conservation CONSERVATION LETTERS Halpern, B. S., Ebert, C. M., Kappel, C. V., Madin, E. M., Micheli, F., Perry, M., Selkoe, K. A., Walbridge, S. 2009; 2 (4): 189-196
  • Imprint of past environmental regimes on structure and succession of a deep-sea hydrothermal vent community OECOLOGIA Mullineaux, L. S., Micheli, F., Peterson, C. H., Lenihan, H. S., Markus, N. 2009; 161 (2): 387-400


    Dramatic perturbations of ecological communities through rapid shifts in environmental regime do not always result in complete mortality of residents. Instead, legacy individuals may remain and influence the succession and composition of subsequent communities. We used a reciprocal transplant experiment to investigate whether a legacy effect is detectable in communities experiencing an abrupt increase or decrease in hydrothermal fluid flux at deep-sea vents. Vent habitats are characterized by strong gradients in productivity and physico-chemical stressors, both of which tend to increase with increasing vent fluid flux. In our experiments, many species survived transplantation from cool (water temperatures <2 degrees C above ambient) to warm (4-30 degrees C above ambient) habitats, resulting in significantly higher species richness on transplanted than remaining experimental substrata. A legacy effect was much less apparent in transplantation from warm to cool habitat, although a few vestimentiferan tubeworms, normally restricted to warm habitat, survived transplantation. The asymmetry in influence of legacy individuals suggests that productivity enhancement may outweigh potential physiological stress in setting limits to distributions of vent invertebrates. This influence of biological processes contrasts with theory developed in the rocky intertidal that predicts the predominance of physical control at the high-stress end of an environmental gradient. Prediction of successional transitions in vents and other habitats experiencing regime shifts in which remnant species may survive must take into account the possible influence of historical effects.

    View details for DOI 10.1007/s00442-009-1390-1

    View details for Web of Science ID 000268548000016

    View details for PubMedID 19551410

  • Mapping cumulative human impacts to California Current marine ecosystems CONSERVATION LETTERS Halpern, B. S., Kappel, C. V., Selkoe, K. A., Micheli, F., Ebert, C. M., Kontgis, C., Crain, C. M., Martone, R. G., Shearer, C., Teck, S. J. 2009; 2 (3): 138-148
  • In the Zone Comprehensive Ocean Protection ISSUES IN SCIENCE AND TECHNOLOGY Kappel, C. V., Halpern, B. S., Martone, R. G., Micheli, F., Selkoe, K. A. 2009; 25 (3): 33-44
  • Design of marine protected areas in a human-dominated seascape MARINE ECOLOGY PROGRESS SERIES Fraschetti, S., D'Ambrosio, P., Micheli, F., Pizzolante, F., Bussotti, S., Terlizzi, A. 2009; 375: 13-24

    View details for DOI 10.3354/meps07781

    View details for Web of Science ID 000263609600002

  • Biotic interactions at hydrothermal vents: Recruitment inhibition by the mussel Bathymodiolus thermophilus DEEP-SEA RESEARCH PART I-OCEANOGRAPHIC RESEARCH PAPERS Lenihan, H. S., Mills, S. W., Mullineaux, L. S., Peterson, C. H., Fisher, C. R., Micheli, F. 2008; 55 (12): 1707-1717
  • Tropical coastal habitats as surrogates of fish community structure, grazing, and fisheries value ECOLOGICAL APPLICATIONS Harborne, A. R., Mumby, P. J., Kappel, C. V., Dahlgren, C. P., Micheli, F., Holmes, K. E., Brumbaugh, D. R. 2008; 18 (7): 1689-1701


    Habitat maps are frequently invoked as surrogates of biodiversity to aid the design of networks of marine reserves. Maps are used to maximize habitat heterogeneity in reserves because this is likely to maximize the number of species protected. However, the technique's efficacy is limited by intra-habitat variability in the species present and their abundances. Although communities are expected to vary among patches of the same habitat, this variability is poorly documented and rarely incorporated into reserve planning. To examine intra-habitat variability in coral-reef fishes, we generated a data set from eight tropical coastal habitats and six islands in the Bahamian archipelago using underwater visual censuses. Firstly, we provide further support for habitat heterogeneity as a surrogate of biodiversity as each predefined habitat type supported a distinct assemblage of fishes. Intra-habitat variability in fish community structure at scales of hundreds of kilometers (among islands) was significant in at least 75% of the habitats studied, depending on whether presence/absence, density, or biomass data were used. Intra-habitat variability was positively correlated with the mean number of species in that habitat when density and biomass data were used. Such relationships provide a proxy for the assessment of intra-habitat variability when detailed quantitative data are scarce. Intra-habitat variability was examined in more detail for one habitat (forereefs visually dominated by Montastraea corals). Variability in community structure among islands was driven by small, demersal families (e.g., territorial pomacentrid and labrid fishes). Finally, we examined the ecological and economic significance of intra-habitat variability in fish assemblages on Montastraea reefs by identifying how this variability affects the composition and abundances of fishes in different functional groups, the key ecosystem process of parrotfish grazing, and the ecosystem service of value of commercially important finfish. There were significant differences in a range of functional groups and grazing, but not fisheries value. Variability at the scale of tens of kilometers (among reefs around an island) was less than that among islands. Caribbean marine reserves should be replicated at scales of hundreds of kilometers, particularly for species-rich habitats, to capture important intra-habitat variability in community structure, function, and an ecosystem process.

    View details for Web of Science ID 000259555900010

    View details for PubMedID 18839764

  • Response to comment on "a global map of human impact on marine ecosystems" SCIENCE Selkoe, K. A., Kappel, C. V., Halpern, B. S., Micheli, F., D'Agrosa, C., Bruno, J., Casey, K. S., Ebert, C., Fox, H. E., Fujita, R., Heinemann, D., Lenihan, H. S., Madin, E. M., Perry, M., Selig, E. R., Spalding, M., Steneck, R., Walbridge, S., Watson, R. 2008; 321 (5895)
  • Reserve effects and natural variation in coral reef communities JOURNAL OF APPLIED ECOLOGY Harborne, A. R., Mumby, P. J., Kappel, C. V., Dahlgren, C. P., Micheli, F., Holmes, K. E., Sanchirico, J. N., Broad, K., Elliott, I. A., Brumbaugh, D. R. 2008; 45 (4): 1010-1018
  • Coral reef habitats as surrogates of species, ecological functions, and ecosystem services CONSERVATION BIOLOGY Mumby, P. J., Broad, K., Brumbaugh, D. R., Dahlgren, C. P., Harborne, A. R., Hastings, A., Holmes, K. E., Kappel, C. V., Micheli, F., Sanchirico, J. N. 2008; 22 (4): 941-951


    Habitat maps are often the core spatially consistent data set on which marine reserve networks are designed, but their efficacy as surrogates for species richness and applicability to other conservation measures is poorly understood. Combining an analysis of field survey data, literature review, and expert assessment by a multidisciplinary working group, we examined the degree to which Caribbean coastal habitats provide useful planning information on 4 conservation measures: species richness, the ecological functions of fish species, ecosystem processes, and ecosystem services. Approximately one-quarter to one-third of benthic invertebrate species and fish species (disaggregated by life phase; hereafter fish species) occurred in a single habitat, and Montastraea-dominated forereefs consistently had the highest richness of all species, processes, and services. All 11 habitats were needed to represent all 277 fish species in the seascape, although reducing the conservation target to 95% of species approximately halved the number of habitats required to ensure representation. Species accumulation indices (SAIs) were used to compare the efficacy of surrogates and revealed that fish species were a more appropriate surrogate of benthic species (SAI = 71%) than benthic species were for fishes (SAI = 42%). Species of reef fishes were also distributed more widely across the seascape than invertebrates and therefore their use as a surrogate simultaneously included mangroves, sea grass, and coral reef habitats. Functional classes of fishes served as effective surrogates of fish and benthic species which, given their ease to survey, makes them a particularly useful measure for conservation planning. Ecosystem processes and services exhibited great redundancy among habitats and were ineffective as surrogates of species. Therefore, processes and services in this case were generally unsuitable for a complementarity-based approach to reserve design. In contrast, the representation of species or functional classes ensured inclusion of all processes and services in the reserve network.

    View details for DOI 10.1111/j.1523-1739.2008.00933.x

    View details for Web of Science ID 000258216600020

    View details for PubMedID 18477024

  • Alteration of seagrass species composition and function over two decades ECOLOGICAL MONOGRAPHS Micheli, F., Bishop, M. J., Peterson, C. H., Rivera, J. 2008; 78 (2): 225-244
  • Persistence of depleted abalones in marine reserves of central California BIOLOGICAL CONSERVATION Micheli, F., Shelton, A. O., Bushinsky, S. M., Chiu, A. L., Haupt, A. J., Heiman, K. W., Kappel, C. V., Lynch, M. C., Martone, R. G., Dunbar, R. B., Watanabe, J. 2008; 141 (4): 1078-1090
  • Understanding and predicting ecological dynamics: Are major surprises inevitable? ECOLOGY Doak, D. F., Estes, J. A., Halpern, B. S., Jacob, U., Lindberg, D. R., Lovvorn, J., Monson, D. H., Tinker, M. T., Williams, T. M., Wootton, J. T., Carroll, I., Emmerson, M., Micheli, F., Novak, M. 2008; 89 (4): 952-961


    Ecological surprises, substantial and unanticipated changes in the abundance of one or more species that result from previously unsuspected processes, are a common outcome of both experiments and observations in community and population ecology. Here, we give examples of such surprises along with the results of a survey of well-established field ecologists, most of whom have encountered one or more surprises over the course of their careers. Truly surprising results are common enough to require their consideration in any reasonable effort to characterize nature and manage natural resources. We classify surprises as dynamic-, pattern-, or intervention-based, and we speculate on the common processes that cause ecological systems to so often surprise us. A long-standing and still growing concern in the ecological literature is how best to make predictions of future population and community dynamics. Although most work on this subject involves statistical aspects of data analysis and modeling, the frequency and nature of ecological surprises imply that uncertainty cannot be easily tamed through improved analytical procedures, and that prudent management of both exploited and conserved communities will require precautionary and adaptive management approaches.

    View details for Web of Science ID 000255580200010

    View details for PubMedID 18481520

  • A global map of human impact on marine ecosystems SCIENCE Halpern, B. S., Walbridge, S., Selkoe, K. A., Kappel, C. V., Micheli, F., D'Agrosa, C., Bruno, J. F., Casey, K. S., Ebert, C., Fox, H. E., Fujita, R., Heinemann, D., Lenihan, H. S., Madin, E. M., Perry, M. T., Selig, E. R., Spalding, M., Steneck, R., Watson, R. 2008; 319 (5865): 948-952


    The management and conservation of the world's oceans require synthesis of spatial data on the distribution and intensity of human activities and the overlap of their impacts on marine ecosystems. We developed an ecosystem-specific, multiscale spatial model to synthesize 17 global data sets of anthropogenic drivers of ecological change for 20 marine ecosystems. Our analysis indicates that no area is unaffected by human influence and that a large fraction (41%) is strongly affected by multiple drivers. However, large areas of relatively little human impact remain, particularly near the poles. The analytical process and resulting maps provide flexible tools for regional and global efforts to allocate conservation resources; to implement ecosystem-based management; and to inform marine spatial planning, education, and basic research.

    View details for DOI 10.1126/science.1149345

    View details for Web of Science ID 000253165700045

    View details for PubMedID 18276889

  • Non-native habitat as home for non-native species: comparison of communities associated with invasive tubeworm and native oyster reefs AQUATIC BIOLOGY Heiman, K. W., Vidargas, N., Micheli, F. 2008; 2 (1): 47-56

    View details for DOI 10.3354/ab00034

    View details for Web of Science ID 000259452400005

  • MODELING STAKEHOLDER PREFERENCES WITH PROBABILISTIC INVERSION Application to Prioritizing Marine Ecosystem Vulnerabilities REAL-TIME AND DELIBERATIVE DECISION MAKING: APPLICATION TO EMERGING STRESSORS Neslo, R., Micheli, F., Kappel, C. V., Selkoe, K. A., Halpern, B. S., Cooke, R. M. 2008: 265-284
  • Evaluating and ranking the vulnerability of global marine ecosystems to anthropogenic threats CONSERVATION BIOLOGY Halpern, B. S., Selkoe, K. A., Micheli, F., Kappel, C. V. 2007; 21 (5): 1301-1315


    Marine ecosystems are threatened by a suite of anthropogenic stressors. Mitigating multiple threats is a daunting task, particularly when funding constraints limit the number of threats that can be addressed. Threats are typically assessed and prioritized via expert opinion workshops that often leave no record of the rationale for decisions, making it difficult to update recommendations with new information. We devised a transparent, repeatable, and modifiable method for collecting expert opinion that describes and documents how threats affect marine ecosystems. Experts were asked to assess the functional impact, scale, and frequency of a threat to an ecosystem; the resistance and recovery time of an ecosystem to a threat; and the certainty of these estimates. To quantify impacts of 38 distinct anthropogenic threats on 23 marine ecosystems, we surveyed 135 experts from 19 different countries. Survey results showed that all ecosystems are threatened by at least nine threats and that nine ecosystems are threatened by >90% of existing threats. The greatest threats (highest impact scores) were increasing sea temperature, demersal destructive fishing, and point-source organic pollution. Rocky reef, coral reef, hard-shelf, mangrove, and offshore epipelagic ecosystems were identified as the most threatened. These general results, however, may be partly influenced by the specific expertise and geography of respondents, and should be interpreted with caution. This approach to threat analysis can identify the greatest threats (globally or locally), most widespread threats, most (or least) sensitive ecosystems, most (or least) threatened ecosystems, and other metrics of conservation value. Additionally, it can be easily modified, updated as new data become available, and scaled to local or regional settings, which would facilitate informed and transparent conservation priority setting.

    View details for DOI 10.1111/j.1523-1739.2007.00752.x

    View details for Web of Science ID 000250008700021

    View details for PubMedID 17883495

  • Human impacts on the species-area relationship reef fish assemblages ECOLOGY LETTERS Tittensor, D. P., Micheli, F., Nystrom, M., Worm, B. 2007; 10 (9): 760-772


    The relationship between species richness and area is one of the oldest, most recognized patterns in ecology. Here we provide empirical evidence for strong impacts of fisheries exploitation on the slope of the species-area relationship (SAR). Using comparative field surveys of fish on protected and exploited reefs in three oceans and the Mediterranean Sea, we show that exploitation consistently depresses the slope of the SAR for both power-law and exponential models. The magnitude of change appears to be proportional to fishing intensity. Results are independent of taxonomic resolution and robust across coral and rocky reefs, sampling protocols and statistical methods. Changes in species richness, relative abundance and patch occupancy all appear to contribute to this pattern. We conclude that exploitation pressure impacts the fundamental scaling of biodiversity as well as the species richness and spatial distribution patterns of reef fish. We propose that species-area curves can be sensitive indicators of community-level changes in biodiversity, and may be useful in quantifying the human imprint on reef biodiversity, and potentially elsewhere.

    View details for DOI 10.1111/j.1461-0248.2007.01076.x

    View details for Web of Science ID 000248598300002

    View details for PubMedID 17663709

  • Response to comments on "Impacts of biodiversity loss on ocean ecosystem services" SCIENCE Worm, B., Barbier, E. B., Beaumont, N., Duffy, J. E., Folke, C., Halpern, B. S., Jackson, J. B., Lotze, H. K., Micheli, F., Palumbi, S. R., Sala, E., Selkoe, K. A., Stachowicz, J. J., Watson, R. 2007; 316 (5829): 1285-1286
  • Designing marine reserves for interacting species: Insights from theory BIOLOGICAL CONSERVATION Baskett, M. L., Micheli, F., Levin, S. A. 2007; 137 (2): 163-179
  • Trophic cascade facilitates coral recruitment in a marine reserve PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA Mumby, P. J., Harborne, A. R., Williams, J., Kappel, C. V., Brumbaugh, D. R., Micheli, F., Holmes, K. E., Dahlgren, C. P., Paris, C. B., Blackwell, P. G. 2007; 104 (20): 8362-8367


    Reduced fishing pressure and weak predator-prey interactions within marine reserves can create trophic cascades that increase the number of grazing fishes and reduce the coverage of macroalgae on coral reefs. Here, we show that the impacts of reserves extend beyond trophic cascades and enhance the process of coral recruitment. Increased fish grazing, primarily driven by reduced fishing, was strongly negatively correlated with macroalgal cover and resulted in a 2-fold increase in the density of coral recruits within a Bahamian reef system. Our conclusions are robust because four alternative hypotheses that may generate a spurious correlation between grazing and coral recruitment were tested and rejected. Grazing appears to influence the density and community structure of coral recruits, but no detectable influence was found on the overall size-frequency distribution, community structure, or cover of corals. We interpret this absence of pattern in the adult coral community as symptomatic of the impact of a recent disturbance event that masks the recovery trajectories of individual reefs. Marine reserves are not a panacea for conservation but can facilitate the recovery of corals from disturbance and may help sustain the biodiversity of organisms that depend on a complex three-dimensional coral habitat.

    View details for DOI 10.1073/pnas.0702602104

    View details for Web of Science ID 000246599900032

    View details for PubMedID 17488824

  • High apex predator biomass on remote Pacific islands CORAL REEFS Stevenson, C., Katz, L. S., Micheli, F., Block, B., Heiman, K. W., Perle, C., Weng, K., Dunbar, R., Witting, J. 2007; 26 (1): 47-51
  • Impacts of biodiversity loss on ocean ecosystem services SCIENCE Worm, B., Barbier, E. B., Beaumont, N., Duffy, J. E., Folke, C., Halpern, B. S., Jackson, J. B., Lotze, H. K., Micheli, F., Palumbi, S. R., Sala, E., Selkoe, K. A., Stachowicz, J. J., Watson, R. 2006; 314 (5800): 787-790


    Human-dominated marine ecosystems are experiencing accelerating loss of populations and species, with largely unknown consequences. We analyzed local experiments, long-term regional time series, and global fisheries data to test how biodiversity loss affects marine ecosystem services across temporal and spatial scales. Overall, rates of resource collapse increased and recovery potential, stability, and water quality decreased exponentially with declining diversity. Restoration of biodiversity, in contrast, increased productivity fourfold and decreased variability by 21%, on average. We conclude that marine biodiversity loss is increasingly impairing the ocean's capacity to provide food, maintain water quality, and recover from perturbations. Yet available data suggest that at this point, these trends are still reversible.

    View details for DOI 10.1126/science.1132294

    View details for Web of Science ID 000241729800037

    View details for PubMedID 17082450

  • Integrating marine protected areas with catch regulation CANADIAN JOURNAL OF FISHERIES AND AQUATIC SCIENCES Hilborn, R., Micheli, F., De Leo, G. A. 2006; 63 (3): 642-649
  • Fishing, trophic cascades, and the process of grazing on coral reefs SCIENCE Mumby, P. J., Dahlgren, C. P., Harborne, A. R., Kappel, C. V., Micheli, F., Brumbaugh, D. R., Holmes, K. E., Mendes, J. M., Broad, K., Sanchirico, J. N., Buch, K., Box, S., Stoffle, R. W., Gill, A. B. 2006; 311 (5757): 98-101


    Since the mass mortality of the urchin Diadema antillarum in 1983, parrotfishes have become the dominant grazer on Caribbean reefs. The grazing capacity of these fishes could be impaired if marine reserves achieve their long-term goal of restoring large consumers, several of which prey on parrotfishes. Here we compare the negative impacts of enhanced predation with the positive impacts of reduced fishing mortality on parrotfishes inside reserves. Because large-bodied parrotfishes escape the risk of predation from a large piscivore (the Nassau grouper), the predation effect reduced grazing by only 4 to 8%. This impact was overwhelmed by the increase in density of large parrotfishes, resulting in a net doubling of grazing. Increased grazing caused a fourfold reduction in the cover of macroalgae, which, because they are the principal competitors of corals, highlights the potential importance of reserves for coral reef resilience.

    View details for DOI 10.1126/science.1121129

    View details for Web of Science ID 000234546300042

    View details for PubMedID 16400152

  • The functional value of Caribbean coral reef, seagrass and mangrove habitats to ecosystem processes ADVANCES IN MARINE BIOLOGY, VOL 50 Harborne, A. R., Mumby, P. J., Micheli, F., Perry, C. T., Dahlgren, C. P., Holmes, K. E., Brumbaugh, D. R. 2006; 50: 57-189


    Caribbean coral reef habitats, seagrass beds and mangroves provide important goods and services both individually and through functional linkages. A range of anthropogenic factors are threatening the ecological and economic importance of these habitats and it is vital to understand how ecosystem processes vary across seascapes. A greater understanding of processes will facilitate further insight into the effects of disturbances and assist with assessing management options. Despite the need to study processes across whole seascapes, few spatially explicit ecosystem-scale assessments exist. We review the empirical literature to examine the role of different habitat types for a range of processes. The importance of each of 10 generic habitats to each process is defined as its "functional value" (none, low, medium or high), quantitatively derived from published data wherever possible and summarised in a single figure. This summary represents the first time the importance of habitats across an entire Caribbean seascape has been assessed for a range of processes. Furthermore, we review the susceptibility of each habitat to disturbances to investigate spatial patterns that might affect functional values. Habitat types are considered at the scale discriminated by remotely-sensed imagery and we envisage that functional values can be combined with habitat maps to provide spatially explicit information on processes across ecosystems. We provide examples of mapping the functional values of habitats for populations of three commercially important species. The resulting data layers were then used to generate seascape-scale assessments of "hot spots" of functional value that might be considered priorities for conservation. We also provide an example of how the literature reviewed here can be used to parameterise a habitat-specific model investigating reef resilience under different scenarios of herbivory. Finally, we use multidimensional scaling to provide a basic analysis of the overall functional roles of different habitats. The resulting ordination suggests that each habitat has a unique suite of functional values and, potentially, a distinct role within the ecosystem. This review shows that further data are required for many habitat types and processes, particularly forereef and escarpment habitats on reefs and for seagrass beds and mangroves. Furthermore, many data were collected prior to the regional mass mortality of Diadema and Acropora, and subsequent changes to benthic communities have, in many cases, altered a habitat's functional value, hindering the use of these data for parameterising maps and models. Similarly, few data exist on how functional values change when environmental parameters, such as water clarity, are altered by natural or anthropogenic influences or the effects of a habitat's spatial context within the seascape. Despite these limitations, sufficient data are available to construct maps and models to better understand tropical marine ecosystem processes and assist more effective mitigation of threats that alter habitats and their functional values.

    View details for Web of Science ID 000238223900002

    View details for PubMedID 16782451

  • Marine Parks Need Sharks? – response Science Mumby, P., Micheli, F., Dahgren, C., Litvin, S., Gill, A., Brumbaugh, D., Broad, K., Sanchirico, J., Kappel, C., Harborne, A., Holmes, K. 2006; 312: 527
  • Selective predation by the zoarcid fish Thermarces cerberus at hydrothermal vents DEEP-SEA RESEARCH PART I-OCEANOGRAPHIC RESEARCH PAPERS Sancho, G., Fisher, C. R., Mills, S., Micheli, F., Johnson, G. A., Lenihan, H. S., Peterson, C. H., Mullineaux, L. S. 2005; 52 (5): 837-844
  • Low functional redundancy in coastal marine assemblages ECOLOGY LETTERS Micheli, F., Halpern, B. S. 2005; 8 (4): 391-400
  • Ecology - Are US coral reefs on the slippery slope to slime? SCIENCE Pandolfi, J. M., Jackson, J. B., Baron, N., Bradbury, R. H., Guzman, H. M., Hughes, T. P., Kappel, C. V., Micheli, F., Ogden, J. C., Possingham, H. P., Sala, E. 2005; 307 (5716): 1725-1726

    View details for DOI 10.1126/science.1104258

    View details for Web of Science ID 000227883900028

    View details for PubMedID 15774744

  • Cascading human impacts, marine protected areas, and the structure of Mediterranean reef assemblages ECOLOGICAL MONOGRAPHS Micheli, F., Benedetti-Cecchi, L., Gambaccini, S., Bertocci, I., Borsini, C., Osio, G. C., Roman, F. 2005; 75 (1): 81-102
  • Ecological science and sustainability for the 21st century FRONTIERS IN ECOLOGY AND THE ENVIRONMENT Palmer, M. A., Bernhardt, E. S., Chornesky, E. A., Collins, S. L., Dobson, A. P., Duke, C. S., Gold, B. D., Jacobson, R. B., Kingsland, S. E., Kranz, R. H., Mappin, M. J., Martinez, M. L., Micheli, F., Morse, J. L., Pace, M. L., Pascual, M., Palumbi, S. S., Reichman, O., Townsend, A. R., Turner, M. G. 2005; 3 (1): 4-11
  • Introduction of non-native oysters: Ecosystem effects and restoration implications ANNUAL REVIEW OF ECOLOGY EVOLUTION AND SYSTEMATICS Ruesink, J. L., Lenihan, H. S., Trimble, A. C., Heiman, K. W., Micheli, F., Byers, J. E., Kay, M. C. 2005; 36: 643-689
  • Reassessing US coral reefs - Response Science Jackson, J., Ogden, J., Pandolfi, J., Baron, N., Bradbury, R., Guzman, H., Hughes, T., Kappel, C., Micheli, F., Possingham, H., Sala, E. 2005; 308: 1741-1742
  • Trajectories and correlates of community change in no-take marine reserves ECOLOGICAL APPLICATIONS Micheli, F., Halpern, B. S., Botsford, L. W., Warner, R. R. 2004; 14 (6): 1709-1723
  • Distribution of plants in a California serpentine grassland: are rocky hummocks spatial refuges for native species? PLANT ECOLOGY Gram, W. K., Borer, E. T., Cottingham, K. L., Seabloom, E. W., Boucher, V. L., Goldwasser, L., Micheli, F., Kendall, B. E., Burton, R. S. 2004; 172 (2): 159-171
  • Ecology for a crowded planet SCIENCE Palmer, M., Bernhardt, E., Chornesky, E., Collins, S., Dobson, A., Duke, C., Gold, B., Jacobson, R., Kingsland, S., Kranz, R., Mappin, M., Martinez, M. L., Micheli, F., Morse, J., Pace, M., Pascual, M., Palumbi, S., Reichman, O. J., Simons, A., Townsend, A., Turner, M. 2004; 304 (5675): 1251-1252

    View details for Web of Science ID 000221669600023

    View details for PubMedID 15166349

  • Including species interactions in the design and evaluation of marine reserves: Some insights from a predator-prey model Micheli, F., Amarasekare, P., Bascompte, J., Gerber, L. R. ROSENSTIEL SCH MAR ATMOS SCI. 2004: 653-669
  • Flow damping under seagrass canopies of differing structure Marine Ecology Progress Series Peterson, C., Luettich Jr, R., Micheli, F., Skilleter, G. 2004; 268: 81-92
  • Successional mechanism varies along a gradient in hydrothermal fluid flux at deep-sea vents ECOLOGICAL MONOGRAPHS Mullineaux, L. S., Peterson, C. H., Micheli, F., Mills, S. W. 2003; 73 (4): 523-542
  • Variation in rocky shore assemblages in the northwestern Mediterranean: contrasts between islands and the mainland JOURNAL OF EXPERIMENTAL MARINE BIOLOGY AND ECOLOGY Benedetti-Cecchi, L., Maggi, E., Bertocci, I., Vaselli, S., Micheli, F., Osio, G. C., Cinelli, F. 2003; 293 (2): 193-215
  • Competition, seed limitation, disturbance, and reestablishment of California native annual forbs ECOLOGICAL APPLICATIONS Seabloom, E. W., Borer, E. T., Boucher, V. L., Burton, R. S., Cottingham, K. L., Goldwasser, L., Gram, W. K., Kendall, B. E., Micheli, F. 2003; 13 (3): 575-592
  • Implications of spatial heterogeneity for management of marine protected areas (MPAs): examples from assemblages of rocky coasts in the northwest Mediterranean MARINE ENVIRONMENTAL RESEARCH Benedetti-Cecchi, L., Bertocci, I., Micheli, F., Maggi, E., Fosella, T., Vaselli, S. 2003; 55 (5): 429-458


    Marine protected areas (MPAs) are increasingly used as a management tool to preserve species and habitats. Testing hypotheses about the effectiveness of MPAs is important for their implementation and to identify informative criteria to support management decisions. This study tested the general proposition that MPAs affected assemblages of algae and invertebrates between 0.0 and 0.5 m above the mean low water level of rocky coasts on two islands in the Tuscan Archipelago (northwest Mediterranean). Protection was concentrated mainly on the west coasts of the islands, raising the possibility that neither the full range of assemblages nor the relevant scales of variation were properly represented within MPAs. This motivated the comparison of assemblages on opposite sides of islands (habitats). The effects of MPAs and habitat were assessed with a multifactorial sampling design; hypotheses were tested about differences in structure of assemblages, in mean abundance of common taxa and in univariate and multivariate measures of spatial variation. The design consisted of three replicate shores for each condition of protected and reference areas on the west side of each island and three unprotected shores on the eastern side. Assemblages were sampled independently four times on each island between June 1999 and January 2001. At each time of sampling two sites were selected randomly at each of two tidal heights to represent midshore and lowshore assemblages on each shore. Estimates of abundance were obtained using non-destructive sampling methods from five replicate 20x20 cm quadrats at each site. Results indicated differences among habitats in structure of assemblages, in mean abundance of common taxa and in univariate and multivariate measures of spatial variation at the scale of shores. Most of these patterns were inconsistent with the predicted effect of management through MPAs. The data suggest that designation of MPAs in the Tuscan Archipelago should proceed through management of multiple shores and types of habitat selected to guarantee protection to a representative sample of assemblages and to the processes responsible for maintenance of spatial patchiness at different scales. This study also shows that considerations of spatial heterogeneity are important to underpin management decisions about the number, size and location of MPAs.

    View details for Web of Science ID 000181740300004

    View details for PubMedID 12628195

  • Principles for the design of marine reserves ECOLOGICAL APPLICATIONS Botsford, L. W., Micheli, F., Hastings, A. 2003; 13 (1): S25-S31
  • Principles for the design of marine reserves Ecological Applications Botsford, L., Micheli, F., Hastings, A. 2003; S13: 25-31
  • Competition, seed limitation, disturbance, and the reestablishment of California native annual forbs Ecological Applications Seabloom, E., Borer, E., Boucher, V., Burton, R., Cottingham, K., Goldwasser, L., Gram, W., Kendall, B., Micheli, F. 2003; 13: 575-592
  • Marine Protected Areas in the Mediterranean Sea: Objectives, Effectiveness and Monitoring MARINE ECOLOGY-PUBBLICAZIONI DELLA STAZIONE ZOOLOGICA DI NAPOLI I Fraschetti, S., Terlizzi, A., Micheli, F., Benedetti-Cecchi, L., Boero, F. 2002; 23: 190-200
  • Predation structures communities at deep-sea hydrothermal vents ECOLOGICAL MONOGRAPHS Micheli, F., Peterson, C. H., Mullineaux, L. S., Fisher, C. R., Mills, S. W., Sancho, G., Johnson, G. A., Lenihan, H. S. 2002; 72 (3): 365-382
  • Temporal, spatial, and taxonomic patterns of crustacean zooplankton variability in unmanipulated north-temperate lakes LIMNOLOGY AND OCEANOGRAPHY Rusak, J. A., Yan, N. D., Somers, K. M., Cottingham, K. L., Micheli, F., Carpenter, S. R., Frost, T. M., Paterson, M. J., McQueen, D. J. 2002; 47 (3): 613-625
  • Interplay of encrusting coralline algae and sea urchins in maintaining alternative habitats MARINE ECOLOGY PROGRESS SERIES Bulleri, F., Bertocci, I., Micheli, F. 2002; 243: 101-109
  • Climate change - Climate change in nontraditional data sets SCIENCE Sagarin, R., Micheli, F. 2001; 294 (5543): 811-811

    View details for Web of Science ID 000171851800034

    View details for PubMedID 11679659

  • Human alteration of food webs - Research priorities for conservation and management Micheli, F., Polis, G. A., Boersma, P. D., Hixon, M. A., Norse, E. A., Snelgrove, P. V., Soule, M. E. ISLAND PRESS. 2001: 31-57
  • Oceans at risk - Research priorities in marine conservation biology CONSERVATION BIOLOGY: RESEARCH PRIORITIES FOR THE NEXT DECADE Hixon, M. A., Boersma, P. D., Hunter, M. L., Micheli, F., Norse, E. A. 2001: 125-154
  • Synthesis of linkages between benthic and fish communities as a key to protecting essential fish habitat BULLETIN OF MARINE SCIENCE Peterson, C. H., Summerson, H. C., Thomson, E., Lenihan, H. S., Grabowski, J., Manning, L., Micheli, F., Johnson, G. 2000; 66 (3): 759-774
  • Biological effects of shellfish harvesting on oyster reefs: resolving a fishery conflict using ecological experimentationt Fishery Bulletin Lenihan, H., Micheli, F. 2000; 98: 86-95
  • Biological effects of shellfish harvesting on oyster reefs: resolving a fishery conflict by ecological experimentation FISHERY BULLETIN Lenihan, H. S., Micheli, F. 2000; 98 (1): 86-95
  • A method to determine rate and pattern of variability in ecological communities Oikos Collins, S., Micheli, F., Hartt, L. 2000; 91: 285-293
  • Eutrophication, fisheries, and consumer-resource dynamics in marine pelagic ecosystems SCIENCE Micheli, F. 1999; 285 (5432): 1396-1398
  • Estuarine vegetated habitats as corridors for predator movements CONSERVATION BIOLOGY Micheli, F., Peterson, C. H. 1999; 13 (4): 869-881
  • The influence of multiple environmental stressors on susceptibility to parasites: An experimental determination with oysters LIMNOLOGY AND OCEANOGRAPHY Lenihan, H. S., Micheli, F., Shelton, S. W., Peterson, C. H. 1999; 44 (3): 910-924
  • The dual nature of community variability OIKOS Micheli, F., Cottingham, K. L., Bascompte, J., Bjornstad, O. N., Eckert, G. L., Fischer, J. M., Keitt, T. H., Kendall, B. E., Klug, J. L., Rusak, J. A. 1999; 85 (1): 161-169
  • Microalgae on seagrass mimics: Does epiphyte community structure differ from live seagrasses? JOURNAL OF EXPERIMENTAL MARINE BIOLOGY AND ECOLOGY Pinckney, J. L., Micheli, F. 1998; 221 (1): 59-70
  • Effects of predator foraging behavior on patterns of prey mortality in marine soft bottoms ECOLOGICAL MONOGRAPHS Micheli, F. 1997; 67 (2): 203-224
  • Effects of previous experience on crab foraging in a mobile and a sedentary species Animal Behaviour Micheli, F. 1997; 53: 1149-1159
  • Predation intensity in estuarine soft bottoms: Between-habitat comparisons and experimental artifacts MARINE ECOLOGY PROGRESS SERIES Micheli, F. 1996; 141 (1-3): 295-302
  • Feeding and burrowing ecology of two East African mangrove crabs Marine Biology Micheli, F., Gherardi, F., Vannini, M. 1991; 111: 247-254
  • FEEDING AND BURROWING ECOLOGY OF 2 EAST-AFRICAN MANGROVE CRABS MARINE BIOLOGY Micheli, F., Gherardi, F., Vannini, M. 1991; 111 (2): 247-254
  • Patterns of movement of the hermit crab, Clibanarius longitarsus, in a mangrove swamp Ethology, Ecology & Evolution Gherardi, F., Micheli, F., Vannini, M. 1990; 2: 312-313
  • Patterns of movement of the hermit crab, Clibanarius longitarsus, in a mangrove swamp Ethology, Ecology & Evolution Gherardi, F., Micheli, F., Vannini, M. 1990; 2: 312-313
  • Growth and reproduction in the freshwater crab Potamon fluviatile Herbst (Decapoda, Brachyura) Freshwater Biology Micheli, F., Gherardi, F., Vannini, M. 1990; 23: 491-503
  • Population structure and relative growth of Potamon potamios in the Dead Sea area Israel Journal of Zoology Gherardi, F., Micheli, F. 1989; 36: 133-145
  • Note sulla biologia ed ecologia del granchio di fiume Potamon fluviatile Bollettino del Museo di Storia Naturale della Lunigiana Gherardi, F., Micheli, F., Monaci, F., Tarducci, F. 1988; 6-7: 169-174