Pelagic Subsidies to Coral Reef Ecosystems
I am interested in how reef-building corals and other reef organisms modify their trophic ecology across gradients of primary production at multiple spatial scales. My work combines field surveys and remotely sensed climatologies of surface ocean production with bulk and compound-specific stable isotope analysis to examine variation in the pelagic contributions to coral reef food webs. To capture a broad range of environmental conditions, I work across natural environmental gradients in the central Pacific and Indian Oceans.
Fox, M.D., Elliot-Smith, E., Smith, J.E., Newsome, S.D. 219. Trophic plasticity in a common reef-building coral: Insights from δ13C analysis of amino acids. Functional Ecology (In press)
Fox, M.D., Williams, G.J., Johnson, M.D., Radice, V.Z., Zgliczynski, B.J., Kelly, E.L.A., Rohwer, F., Sandin, S.A., Smith, J.E. 2018. Gradients in primary production predict the trophic strategies of mixotrophic corals at multiple spatial scales. Current Biology 28:1-9.
Zgliczynski, B.J., Williams, G.J., Hamilton, S.L., Fox, M.D., Eyaud, Y., Cordner, E.G., Michener, R.H., Kaufman, L.S., Sandin, S.A. 2019. Patterns of trophic structure in a complex marine food web. Oecologia (In Press).
Radice, V.Z., Brett, M.T., Fry, B., Fox, M.D., Hoegh-Guldberg, O., Dove, S.G. 2019. Evaluating coral trophic strategies using fatty acid composition and indices. PlosOne, 14(9): e0222327.
Radice, V.Z., Hoegh-Guldberg, O., Fry, B., Fox. M.D., Dove, S.G. 2019. Coral isotopic compositions across the reef slope: Indicators of upwelling in a remote atoll system. Functional Ecology, DOI: 10.1111/1365-2435.13314
Miller, S.D., Zgliczynski, B.J., Fox, M.D., Kaufman, L.S., Michener, R.H., Sandin, S.A., Hamilton, S.L. 2019. Niche width expansion of coral reef fishes along a primary productivity gradient in the remote central Pacific. Marine Ecology Progress Series 625: 127–143.
Williams, G.J., Sandin, S.A., Zgliczynski, B.J., Fox, M.D., Gove, J.M., Rogers, J.S., Furby, K.A., Hartmann, A.C, Caldwell, Z.R., Price, N.N., Smith, J.E. 2018. Biophysical drivers of coral trophic depth zonation. Marine Biology, 165:60.
Community Dynamics and Coral Resilience in the central Pacific
The coral reefs of the central Pacific were among the hardest hit by the global bleaching event in 2015. In this region, the islands of Kiritimati and Jarvis experienced unprecedented thermal stress and high levels of coral mortality. However, other islands in the Line and Phoenix Archipelagos experienced less (but still severe) thermal stress and the coral populations on these islands suffered lower levels of mortality. Using a combination of long-term benthic monitoring data, hydrodynamic modeling, remote sensing, and stable isotope analyses I am working on understanding drivers of coral resilience to thermal stress in this dynamic region.
Fox, M.D., Carter, A.L., Edwards, C.B., Takeshita, Y., Johnson, M.D., Petrovic, V., Amir, C., Sala, E., Sandin, S.A., Smith, J.E. 2019. Limited coral mortality following acute thermal stress and widespread bleaching on Palmyra Atoll, central Pacific. Coral Reefs, DOI:10.1007/s00338-019-01796-7
Carter, A.C., Edwards, C.B., Fox, M.D., Amir, C., Johnson, M.D., Lewis, L.S., Sandin, S.A., Smith, J.E. 2019. Spatial and temporal dynamics of the corallimorph, Rhodactis howesii, at Palmyra Atoll. Coral Reefs (In Press)
Inorganic Nutrient Enrichment on coral reefs
Many coral reefs occur in naturally oligotrophic (nutrient-poor) regions of the ocean but emerging evidence suggests that corals can thrive across a wide range of natural nutrient concentrations. In fact, some of the healthiest, most productive reef ecosystems are situated in the upwelling region of the central Pacific where high inorganic nutrient concentrations are exceptionally high. I am collaborating with Drs. Craig Nelson (UH Manoa), Tom Oliver (NOAA), and Hollie Putnam (URI) to explore the response of corals to a broad range of inorganic nutrient concentrations that reflect typical values observed across the Pacific. Our work seeks to uncover the acclimation responses of coral holobionts from the levels of gene expression and microbial community assembly to whole organism photophysiology.
Fox, M.D., Nelson, C.E., Oliver, T.A., *Quinlan, Z.A, Remple, K., *Glanz, J., Smith, J.E., Putnam, H.M. Differential resistance and acclimation of two Hawaiian coral species to chronic nutrient enrichment reflect life history traits. In review
Quinlan, Z.A., Remple, K., Fox, M.D., Silbiger, N.J., Oliver, T.A., Putnam, H.M., Wegley-Kelly, L., Carlson, C.A., Donahue, M.J., Nelson, C.E. 2018. Fluorescent organic exudates of corals and algae in tropical reefs are compositionally distinct and increase with nutrient enrichment. Limnology and Oceanography Letters DOI:10.1002/lol2.10074.
Silbiger, N.A, Nelson, C.A., Remple, K., Sevilla, J., Quinlan, Z., Putnam, H., Fox, M.D., Donahue, M. Nutrient pollution disrupts key ecosystem functions on coral reefs. Proc. R. Soc. B 285: 20172718.
Kelp and Macroalgal Ecophysiology
My master's research used bulk stable isotopes to show that canopy biomass of giant kelp supports the growth of young fronds by supplying them with fixed carbon. Using manipulative experiments to simulate the removal of biomass by large wave events, I found that a reduction in canopy biomass directly inhibited the growth of new fronds and that the isotopic composition of young fronds provides a proxy for regrowth potential. This work highlights the importance of considering the spatial variation of biomass loss among giant kelp individuals as it will likely impact biomass and regrowth dynamics at the community scale. Ongoing work is focused on, 1) how phylogenetic relatedness among kelps (i.e., annual vs perirenal families) constrains the effects of biomass loss on growth and reproduction and 2) investigating the physiological drivers of carbon isotope fractionation in macroalgae.
Fox, M.D. 2016. Biomass loss reduces growth and resource translocation in giant kelp, Macrocystis pyrifera.
Marine Ecology Progress Series, 526: 65-77 [PDF]
Fox, M.D. 2013. Resource translocation drives δ13C fractionation during recovery from disturbance in giant kelp, Macrocystis pyrifera. Journal of Phycology 49: 811-15. [PDF]
Graham, M.H., Fox, M.D., and Hamilton, S.L. Macrophyte productivity and the provisioning of energy and habitat to nearshore systems. 2016. In: Marine Macrophytes as Foundation Species (ed. Olafsson, E.), Science Publisher/CRC Press, Boca Raton, FL. ISBN 978-1-498-72324-4,pp. 131-160. [PDF]