Bachelor of Science, Biology, Dartmouth College, 2005
Broadly, I am interested in the role of large predatory marine fishes in the pelagic ecosystem. This covers a lot of ground: where do migratory marine predators go, and what drives this? How do physiological differences impact foraging ecology in pelagic fish? What are the feeding hotspots in the open ocean, and what environmental variables determine these hotspots?
I use electronic tagging, stable isotope analysis, and traditional dietary analysis techniques for a multi-faceted approach to studying foraging ecology in marine predators.
Can stable isotope signatures in slow-turnover tissue (i.e. muscle) tell us where a predator has been in the Pacific Ocean? I am using 13C and 15N signatures in tunas, sharks, and other pelagic fish to estimate time spent foraging in broadscale regions of high use in the eastern and central Pacific Ocean.
How does endothermic capacity effect feeding behavior? The evolution of endothermy in fish has long been said to allow horizontal and vertical niche expansion. I am interested in how species with varying endothermic capacities differ in feeding strategies when they overlap in space and time. As a model system I am using data from yellowfin, Pacific bluefin, and albacore tunas when they overlap in the Southern California Bight. I am examining their spatial and trophic ecology using electronic tag data, stable isotope analysis, and dietary analysis.
What are the pelagic hotspots in the Eastern Pacific and what environmental variables are associated with them? I am using digestion-based warming in archivally tagged albacore tuna to estimate feeding in their aggregation regions in the Pacific. I am then using remote-sensed chlorophyll, temperature, and other variables to gain insight into what drives regions of productive feeding for tunas.
Madigan DJ, Baumann Z, Snodgrass OE, Ergül HA, Dewar H, NS Fisher. 2013. Radiocesium in Pacific bluefin tuna Thunnus orientalis in 2012 validates new tracer technique. Environmental Science & Technology, DOI: 10.1021/es4002423. PDF & LINK
Madigan, D. J., Baumann, Z., Carlisle, A. B., Hoen, D. K., Popp, B. N., Munch, S., Dewar, H., Snodgrass, O. E., Block, B. A., & Fisher, N. S. A new tracer toolbox reveals migration patterns of a pelagic predator, Pacific bluefin tuna Thunnus orientalis. in prep.
Fisher, N. S., Beaugelin-Seiller, K., Hinton, T. G., Baumann, Z., Madigan, D. J., & Garnier-LaPlace, J. An evaluation of radiation doses and associated risk from the Fukushima nuclear accident to marine biota and human consumers of seafood. Proc. Natl. Acad. Sci. U.S.A., submitted.
Madigan, D. J.; Baumann, Z.; Fisher, N. S. Pacific bluefin tuna transport Fukushima-derived radionuclides from Japan to California. Proc. Natl. Acad. Sci. U.S.A. 2012, 109 (24), 9483-9486. PDF & LINK
Madigan, D. J., Carlisle, A. B., Dewar, H., Snodgrass, O. E., Litvin, S. Y., Micheli, F., & Block, B. A. Stable isotope analysis challenges wasp-waist food web assumptions in an upwelling pelagic food web. Sci. Rep. 2012, 2 (654), e654. PDF & LINK
Madigan, D. J., Litvin, S. Y., Popp, B. N., Carlisle, A. B., Farwell, C. J., & Block, B. A. Tissue turnover rates and isotopic trophic discrimination factors in the endothermic teleost, Pacific bluefin tuna (Thunnus orientalis). PLoS ONE 2012, 7 (11), e49220. doi:49210.41371/journal.pone.0049220. PDF & LINK
Carlisle, A.B., S.L. Kim, B.X. Semmens, D.J. Madigan, S.J. Jorgensen, et al. 2012. Using Stable Isotope Analysis to Understand the Migration and Trophic Ecology of Northeastern Pacific White Sharks (Carcharodon carcharias). PLoS ONE 7(2): e30492. doi:10.1371/journal.pone.0030492 PDF
Burge, E. J.; Madigan, D. J.; Burnett, L. E.; Burnett, K. G. Lysozyme gene expression by hemocytes of Pacific white shrimp, Litopenaeus vannamei, after injection with Vibrio. Fish & shellfish immunology 2007, 22 (4), 327-339.LINK
Madigan, D.J. & C. Safina. Eating Tuna: What's in Your Roll? What's in Your Can? Huffington Post