Charlie Martin is an Assistant Professor in the Department of Marine Sciences at the University of South Alabama and a Senior Marine Scientist at the Dauphin Island Sea Lab. He completed his undergraduate and Ph.D. at the University of South Alabama and served as a postdoctoral researcher at Louisiana State University.
Prior to joining the faculty, he was a faculty member at the University of Florida Nature Coast Biological Station. Charlie’s research focuses on estuarine and coastal ecology, most notably the effects of anthropogenic stressors on ecological systems.
In my lab, we conduct broad and applied ecological research focused on the conservation of marine and estuarine ecosystems. Specifically, we seek to identify the effects of anthropogenic stressors on coastal ecosystems using field-oriented and experimental approaches.
My research program focuses on question-driven research, and, as such, I seek organisms/systems providing novel ecological insight rather than focusing on organism-specific hypotheses.
The ultimate objective of our research is to gain a fundamental understanding of the ecological processes structuring natural ecosystems, particularly how anthropogenic perturbations have modified these processes, with a specific emphasis on the continued conservation of Gulf of Mexico estuaries, such as the Mobile-Tensaw Delta in Alabama.
Our lab’s research foci are thus very broad, though we tend to focus on several overarching topics:
Introduced species are among the greatest of all threats to the structure and function of native ecosystems. We have worked extensively with freshwater invaders that extend their distribution into estuaries, such as Eurasian milfoil, hydrilla, apple snails, and Nile tilapia.
Overall, we seek to:
- link environmental conditions to field distributions to determine factors limiting dispersal into estuaries,
- determine the ecological effects of these novel species, and
- provide management recommendations for mitigating, restoring, and preventing invasions.
I currently serve editorial roles for several invasive species journals and continue to pursue an understanding of coastal invaders.
Salinity Alteration in Estuaries
Along the Gulf coast, freshwater is a key resource, and alterations to hydrology can drastically modify our estuaries.
For example, reductions in freshwater discharge contributed to the recent collapse of oysters in Apalachicola Bay, Florida.
In Louisiana, wetlands are being lost at an unprecedented rate of over 40 km 2 per year, largely due to a lack of sediment supply supplied from the freshwater inflow.
One solution to arrest this wetland loss is to reestablish the natural hydrology of the delta, through freshwater diversions from the Mississippi River that will bring sediment from the river to replace lost land.
We are currently investigating the reintroduction of the Mississippi River near Port Sulphur, Louisiana to determine how freshwater introduction will affect faunal community composition and food webs in restored and unrestored marshes.
Moreover, ongoing work in the Mobile-Tensaw Delta seeks to determine the effect of barriers such as the Hwy 90 causeway on local ecological structure and function.
Plant-Animal and Food Web Interactions
Key interactions among animals, their habitats, and plants can have a strong, structuring role in estuarine systems.
Our lab studies the relationships between animals and their habitats (e.g., habitat associations, herbivory, refugia, etc.) as well as how individual interactions may scale up to the broader food web.
In addition, recent evidence has indicated that the mere presence of predators can have strong, cascading impacts throughout the food web (i.e., ‘the ecology of fear’).
We seek to determine factors influencing how prey recognize and respond to the threat of predators and the multitude of factors and stressors that can disrupt these interactions.
Given the continued loss of habitat in many areas, environmental managers have turned to restoration practices to re-establish ecosystem functioning and supplement local fisheries. Our group has worked extensively on various restoration projects, including submerged vegetation, oyster reefs, and salt marshes.
Moreover, our lab has investigated restoration in numerous ways – from determining restoration of ecosystem services (such as habitat for nekton) to best management practices and novel techniques for restoring critical estuarine habitat.
Climate Change and Other Disturbances
Global climates are changing rapidly, with rising sea levels, increasing weather variability affecting freshwater discharge, and intensifying temperatures. Changes to these environmental conditions have consequences for estuaries.
We have studied the effects of such changes, including the “tropicalization” of coastal areas, the effects of high-intensity storms such as Hurricane Michael, and (as previously noted) salinity alterations.
Of specific note is our work with range-expanding, tropically-associated consumers such as Common Snook, including documenting their spread, monitoring seasonal movements and thermal refuge use in coastal springs using acoustic telemetry, and quantifying interactions with resident organisms in the Suwannee River watershed.
We are also interested in the ecological effects of other unplanned anthropogenic disturbances – including oil perturbations (e.g., the Deepwater Horizon oil spill), fish kills, and hypoxic conditions.
- McDonald, A.M., C.W. Martin, C.R. Adams, L.K. Reynolds. In Press. Competition in a changing world: environmental stressors during seasonal vulnerability limits benefit of resource pulse to invasive macrophyte. Ecosphere.
- Keppeler, F., J. Junker, M. Shaw, A. Engel, A.M. McDonald, B.J. Roberts, C.W. Martin, E.M. Swenson, J.A. Olin, L.M. Bui, M.J. Polito, N.N. Rabalais, O.P. Jensen, P.C. Lopez-Duarte, R. Rossi, S.B. Alford. In Press. Can created marshes harbor similar biodiversity to natural marshes? A scale-dependent approach from microbes to top predators. Ecosphere.
- Martin, C.W., A. McDonald, J. Valentine, B. Roberts (2023) Towards relevant ecological experiments and assessments of coastal oil spill effects: insights from the 2010 Deepwater Horizon oil spill. Frontiers in Environmental Science. Volume 10. https://doi.org/10.3389/fenvs.2022.1092097
- Looby, A., S. Vela, K.D. Cox, A. Riera, S. Bravo, H.L. Davies, R. Rountree, L.K. Reynolds, C.W Martin, S. Matwin, F. Juanes (2023) FishSounds Version 1.0: A website for the compilation of fish sound production information and recordings. Ecological Informatics. 74:101953. https://doi.org/10.1016/j.ecoinf.2022.101953
- Thomas, T., W.W. Boone, M.S. Allen, C.W. Martin, S.A. Johnson (2022) Occupancy of the diamondback terrapin Malaclemys terrapin on coastal islands in the Suwannee estuary. Herpetological Conservation and Biology 17(3):560–566. https://www.herpconbio.org/Volume_17/Issue_3/Thomas_etal_2022.pdf
- Rohal, C.B., C.R. Adams, C.W. Martin, S. Tevlin, L.K. Reynolds (2022) Intraspecific variation in Potamogeton illinoensis life history and seed germination has implications for restoration in eutrophic lakes. Hydrobiologia 849(16):3481-3500. https://doi.org/10.1007/s10750-022-04947-0
- Correia, K.M., S.B. Alford, B.A. Belgrad, K.M. Darnell, M.Z. Darnell, B.T. Furman, M.O. Hall, C.T. Hayes, C.W. Martin, A. McDonald, D.L. Smee (2022) Drift macroalgae positively influence seagrass associated nekton communities of the northern Gulf of Mexico. Frontiers in Environmental Science. 1194. https://doi.org/10.3389/fenvs.2022.939296
- Correia, K.M., S.B. Alford, B.A. Belgrad, K.M. Darnell, M.Z. Darnell, B.T. Furman, M.O. Hall, C.T. Hayes, C.W. Martin, A. McDonald, D.L. Smee. (2022) Drift macroalgae distribution in northern Gulf of Mexico seagrass meadows. PeerJ e13855. https://doi.org/10.7717/peerj.13855
- Hayes, C.T., S.B. Alford, B.A. Belgrad, K.M. Correiag, M.Z. Darnell, B.T. Furman, M.O. Hall, C.W. Martin, A. McDonald, D.L. Smee, K.M. Darnell. (2022) Regional variation in seagrass complexity drives blue crab (Callinectes sapidus) growth and mortality across the northern Gulf of Mexico. Marine Ecology Progress Series. 693:141-155. https://doi.org/10.3354/meps14084
- Martin, C.W., J.F. Valentine (2022) Climate-induced distribution changes in seagrass ecosystems: lessons from invasion ecology. Frontiers in Marine Science. 9:867173. https://doi.org/10.3389/fmars.2022.867173
- Lewis, K., R.R. Christian, C.W. Martin, K. Allen, A.M. McDonald, V. Roberts, M. Schaffer, J.F. Valentine (2022) Complexities of disturbance response in a marine food web. Limnology and Oceanography. 67(S1):S352-S364. https://doi.org/10.1002/lno.11790
- Looby, A., K.D. Cox, S. Bravo, R. Rountree, F. Juanes, L.K. Reynolds, C.W Martin (2022) A quantitative inventory of global soniferous fish diversity. Reviews in Fish Biology and Fisheries. 32:581-595. https://doi.org/10.1007/s11160-022-09702-1
- Walters, K., C.W. Martin, T. Funk (2022) Differences in habitat structure and resident prey survival on newly restored and established natural intertidal oyster reefs. Restoration Ecology. 30(7):e13630. https://doi.org/10.1111/rec.13630
- McDonald, A.M., C.W. Martin, G.R. Rieucau, B.J. Roberts (2022) Prior exposure to weathered oil influences foraging of an ecologically important saltmarsh resident fish. PeerJ 10:e12593. https://doi.org/10.7717/peerj.12593
- Martin, C.W., L.K. Reynolds, W.A. Scheffel, S. Tiffany, S. Kopetman (2021) Diel variability and influence of artificial light on fish and macroinvertebrate communities in Gulf of Mexico seagrass beds. Estuaries and Coasts 44(2):431-441. https://doi.org/10.1007/s12237-020-00865-3
- Keppeler, F., J.A. Olin, P.C. Lopez-Duarte, M.J. Polito, L.M. Hooper-Bui, S.S. Taylor, N.N. Rabalais, F.J. Fodrie, B.J. Roberts, R.E. Turner, C.W. Martin, O.P. Jensen (2021) Body size, trophic position, and the coupling of different energy pathways across a saltmarsh landscape. Limnology and Oceanography Letters 6(6):360-368. https://doi.org/10.1002/lol2.10212
- Rohal, C.B., L.K. Reynolds, C.R. Adams, C.W. Martin, S.B. Gorham (2021) A preliminary investigation of umbellate inflorescences in Vallisneria americana populations of Central Florida. Aquatic Botany 175(2021):103436. https://doi.org/10.1016/j.aquabot.2021.103436
- Reynolds, L.K., W.A. Scheffel, C.R. Adams, C.W. Martin, C.B. Rohal, J. Slater (2021) Submerged aquatic vegetation species and cultivars within species respond differently to common environmental stressors. Environmental Management 68:477-490. https://doi.org/10.1007/s00267-021-01517-3
- Looby, A., L.K. Reynolds, C.R. Adams, S.J. Walsh, C.W. Martin (2021) Submerged aquatic vegetation habitat use of age-0 largemouth bass Micropterus salmoides. Environmental Biology of Fishes 104:947-958. **Editor’s Choice** https://doi.org/10.1007/s10641-021-01126-3
- Belgrad, B.A., K.M. Correia, K. M. Darnell, M.Z. Darnell, C.T. Hayes, M.O. Hall, B.T. Furman, C.W. Martin, D.L. Smee (2021) Environmental drivers of seagrass-associated nekton abundance and functional groups across the northern Gulf of Mexico. Estuaries and Coasts 44(8):2279-2290. https://doi.org/10.1007/s12237-021-00927-0
- Colombano, D.D., S.Y. Litvin, S.Z. Ziegler, S.B Alford, R. Baker, M. Barbieu, J. Cebrian, R. Connolly, C.A. Currin, L. Deegan, J. Lesser, C.W. Martin, A.E. McDonald, C. McLuckie, B.H. Morrison, J.W. Pahl, L. Risse, J. Smith, L.W. Staver, R.E. Turner, N.J. Waltham (2021) Climate change implications for tidal marshes and food web linkages to estuarine and coastal nekton. Estuaries and Coasts 44:1604-1618. https://doi.org/10.1007/s12237-020-00891-1
- Gilby, B.L., M.P. Weinstein, R. Baker, J. Cebrian, S.B. Alford, A. Chelsky, D.D. Colombano, R. Connolloy, C. Currin, I. Feller, A. Frank, J.A. Goecke, L.A. Gaines, F.E. Hardcastle, C. Henderson, C.W. Martin, A.E. McDonald, B.H. Morrison, A.D. Olds, J.S. Rehage, J. S., N.J. Waltham, S.L. Ziegler (2021) Human actions alter tidal marsh seascapes and the provision of ecosystem services. Estuaries and Coasts 44:1628-1636. https://doi.org/10.1007/s12237-020-00830-0
- Ziegler, S.L., R. Baker, S. Crosby, M. Barbeau, J. Cebrian, D.D. Colombano, R. Connolly, L.A. Deegan, B. Gilby, D. Mallick, D., C.W. Martin, J. Nelson, J. Reinhardt, C. Simenstad, N. Waltham, T. Worthington, L. Rozas (2021) Geographic variation in salt marsh structure and function for nekton: a guide to finding commonality across multiple scales. Estuaries and Coasts 44:1497-1507. https://doi.org/10.1007/s12237-020-00894-y
- Looby, A., L.K. Reynolds, C.R. Adams, C.W. Martin (2021) Submerged aquatic vegetation patch size affects fish communities in a turbid-algal lake. Frontiers in Conservation Science 2:657691. https://doi.org/10.3389/fcosc.2021.657691
- Sullivan, C.R., A.R. Smyth, C.W. Martin, L.K. Reynolds (2021) How does mangrove expansion affect structure and function of adjacent seagrass meadows? Estuaries and Coasts 44(2):453-467. https://doi.org/10.1007/s12237-020-00879-x
- Rohal, C.B., L.K. Reynolds, C.R. Adams, C.W. Martin, E. Latimer, S.J. Walsh, J. Slater (2021) Biological and practical tradeoffs in planting techniques for submerged aquatic vegetation. Aquatic Botany 170(2021):103347. https://doi.org/10.1016/j.aquabot.2020.103347
- Baker, R., M.D. Taylor, K.W. Able, M.W. Beck, J. Cebrian, D.D. Colombano, R.M. Connolly, C. Currin, L.A. Deegan, I. Feller, B.L. Gilby, M.E. Kimball, T.J. Minello, L.P. Rozas, C. Simenstad, R.E. Turner, N.J. Waltham, M.P. Weinstein, S.L. Zieglerg, P.S.E. zu Ermgassen, C. Alcott, S. Alford, M.A. Barbeau, S.C. Crosby, K. Dodds, A. Frank, J. Goeke, L.A. Gaines, F. Hardcastle, C.J. Henderson, W.R. James, M.D. Kenworthy, J. Lesser, D. Mallick, C.W. Martin, A. McDonald, C. McLuckie, B.H. Morrison, J.A. Nelson, G.S. Norris, J. Ollerhead, J. Pahl, S. Ramsden, J. Rehage, J. Reinhardt, R.J. Rezek, L. Risse, J. Smith, E.L. Sparks, L.W. Staver (2020) Fisheries rely on threatened salt marshes. Science 370(6517):670-671. https://doi.org/10.1126/science.abe9332
- Martin, C.W., A.M. McDonald, G.R. Rieucau, B.J. Roberts (2020) Previous oil exposure alters Gulf Killifish Fundulus grandis oil avoidance behavior. PeerJ 8:e10587. https://doi.org/10.7717/peerj.10587
- Rohal, C., L.K. Reynolds, C. R. Adams, C. W. Martin (2020) Pondweeds of Florida. EDIS 2020(5). https://doi.org/10.32473/edis-ss686-2020
- Martin, C.W., K.A. Lewis, A.M. McDonald, T.P. Spearman, S.B. Alford, R. Christian, J.F. Valentine (2020) Disturbance-driven changes to northern Gulf of Mexico nekton communities following the Deepwater Horizon oil spill: evidence for the need for expanded coastal monitoring systems. Marine Pollution Bulletin 155:111098. https://doi.org/10.1016/j.marpolbul.2020.111098
- Purtlebaugh, C., C.W. Martin, M.S. Allen (2020) Poleward expansion of Common Snook Centropomus undecimalis in the northeastern Gulf of Mexico and future research needs. PLoS ONE 15(6):e0234083. https://doi.org/10.1371/journal.pone.0234083
- Reynolds, L.K., C.R. Adams, E. Latimer, C.W. Martin, C. Rohal, J. Slater (2020). A Comparison of Planting Techniques for Submerged Aquatic Vegetation. EDIS 2020(4). https://doi.org/10.32473/edis-ss685-2020
- Martin, C.W., J. F. Valentine (2019) Does invasion of Eurasian milfoil Myriophyllum spicatum lead to a “trophic dead end” and reduced food web complexity in Gulf of Mexico estuarine food webs? Frontiers in Environmental Science 7:166. https://doi.org/10.3389/fenvs.2019.00166
- Jensen, O., C.W. Martin, K.L. Oken, F.J. Fodrie, P.C. Lopez-Duarte, K.W. Able, B.J. Roberts (2019) Simultaneous estimation of dispersal and survival of the gulf killifish Fundulus grandis from a batch-tagging experiment. Marine Ecology Progress Series 624:183-194. https://doi.org/10.3354/meps13040
- Martin, C.W., E.M. Swenson (2018) Herbivory of Oil-Exposed Submerged Aquatic Vegetation Ruppia maritima. PLoS ONE 13(12):e0208463. https://doi.org/10.1371/journal.pone.0208463
- Vastano, A., K. Able, O. Jensen, P. Lopez-Duarte, C.W. Martin, B.J. Roberts (2018) Correction to: Age validation and seasonal growth patterns of a subtropical marsh fish: the Gulf killifish, Fundulus grandis. Environmental Biology of Fishes 101:1307. https://doi.org/10.1007/s10641-018-0777-4
- Kauffman, T.C., C.W. Martin, and J.F. Valentine (2018)Hydrological alteration exacerbates the negative impacts of invasive Eurasian milfoil Myriophyllum spicatum by creating hypoxic conditions in a northern Gulf of Mexico estuary. Marine Ecology Progress Series 592:97-108. https://doi.org/10.3354/meps12517
- Vastano, A., K. Able, O. Jensen, P. Lopez-Duarte, C.W. Martin, B.J. Roberts (2017) Age validation and seasonal growth patterns of a subtropical marsh fish: the Gulf Killifish, Fundulus grandis. Environmental Biology of Fishes 100(10):1315-1327. https://doi.org/10.1007/s10641-018-0777-4
- Martin, C.W. (2017) Avoidance of oil contaminated sediments by marsh fishes: impacts of oiling on habitat occupancy patterns. Marine Ecology Progress Series 576:125-134. https://doi.org/10.3354/meps12084
- Burks, R.L., J. Bernatis, J. Byers, J. Carter, C.W. Martin, B. McDowell, J. van Dyke (2017). “Identity, reproductive potential, distribution, ecology and management of invasive Pomacea maculata in the southern United States.” In Biology and management of invasive apple snails. Eds. Joshi, R.C., R.H. Cowie, L.S. Sebastian. Philippine Rice Research Institute, Maligaya, Science City of Munoz, Nueva Ecija 3119. 406 pp.
- McCann, M., K. Able, F.J. Fodrie, O.P. Jensen, J. Johnson, P. Lopez-Duarte, C.W. Martin, J. Olin, M. Polito, B. Roberts, S. Ziegler. (2017) Key taxa in food web responses to stressors: The Deepwater Horizon Oil Spill. Frontiers in Ecology and the Environment 15(3):142-149. https://doi.org/10.1002/fee.1474
- Martin, C.W. (2017) Effects of macrophyte-specific olfactory cues on fish preference patterns. Aquatic Ecology 51(1):159-165. https://doi.org/10.1007/s10452-016-9606-z
- Martin, C.W., J. Valentine, S. Scyphers, T. Kauffman, J. Dindo (2016) Preliminary Analysis of the Effects of the Macondo Oil Spill on Coastal Diving Ducks in the Northern Gulf of Mexico. Journal of Applied Life Sciences 8(3):1-9. https://doi.org/10.9734/JALSI/2016/28874
- Martin, C.W., L.C. Hollis, R.E. Turner (2015) Effects of oil-contaminated sediments on submerged vegetation: an experimental assessment of Ruppia maritima. PLoS ONE 10(10):e0138797. https://doi.org/10.1371/journal.pone.0138797
- Scyphers, S.B., S.P. Powers, J.M. Drymon, C.W. Martin, P. Schofield, Z.H. Schobernd, R.L. Shipp, T.S. Switzer (2015) The role of citizens in detecting and responding to a rapid marine invasion. Conservation Letters 8(4):242-250. https://doi.org/10.1111/conl.12127
- Able, K.W., P.C. Lopez-Duarte, F.J. Fodrie, O. Jensen, C.W. Martin, B. Roberts, J. Valenti, K. O’Connor, S. Halbert (2015) Fish assemblages in Louisiana Salt Marshes: Effects of the Macondo Oil Spill. Estuaries and Coasts 38(5):1385-1398. https://doi.org/10.1007/s12237-014-9890-6
- Martin, C.W. (2014) Naïve prey exhibit reduced antipredator behavior and survivorship. PeerJ 2:e665. https://doi.org/10.7717/peerj.665
- Martin, C.W., J.F. Valentine. (2014) Tolerance of the island apple snail (Pomacea maculata) to estuarine conditions. Aquatic Ecology 48(3):321-326. https://doi.org/10.1007/s10452-014-9486-z
- Fodrie, F.J., K.W. Able, F. Galvez, K.L. Heck, O.P. Jensen, P.C. Lopez-Duarte, C.W. Martin, R.E. Turner, A. Whitehead (2014) Integrating organismal and population responses of estuarine fishes in Macondo Spill research. Bioscience 64(9):778-788. https://doi.org/10.1093/biosci/biu123
- Martin, C.W., J.F. Valentine (2014) Sexual and asexual reproductive strategies of invasive Eurasian milfoil (Myriophyllum spicatum) in estuarine environments. Hydrobiologia 727(1):177-184. https://doi.org/10.1007/s10750-013-1798-9
- Rozas, L.P, C.W. Martin, J.F. Valentine (2013) Effect of reduced hydrological connectivity on the nursery use of shallow estuarine habitats within a river delta. Marine Ecology Progress Series 492:9-20. https://doi.org/10.3354/meps10486
- Martin, C.W., K.M. Bayha, and J.F. Valentine (2012) Establishment of the Invasive Island Apple Snail Pomacea insularum (Gastropoda: Ampullaridae) and Eradication Efforts in Mobile, Alabama, USA. Gulf of Mexico Science 2012(1-2):30-38. https://doi.org/10.18785/goms.3001.05
- Martin, C.W., J.F. Valentine (2012) Eurasian milfoil invasion in estuaries: Physical disturbance can reduce the proliferation of an aquatic nuisance species. Marine Ecology Progress Series 449:109-119. https://doi.org/10.3354/meps09515
- Puntila, R.I., C.W. Martin, J.F. Valentine (2012) Measuring predation with a new design of submersible chronographic timer. Bulletin of Marine Science 88(4):1115-1122. https://doi.org/10.5343/bms.2012.1011
- Martin, C.W., J.F. Valentine (2011) Impacts of a habitat-forming exotic species on estuarine structure and function: an experimental assessment of Eurasian milfoil. Estuaries and Coasts 34(2):364-372. https://doi.org/10.1007/s12237-010-9274-5
- Martin, C.W. (2011) Shifting paradigms in invasion ecology. Journal of Ecosystem and Ecography 1(2):e101. https://doi.org/10.4172/2157-7625.1000e101
- Martin, C.W., M.M. Valentine, J.F. Valentine (2010) Competitive interactions between invasive Nile tilapia and native fish: the potential for altered trophic exchange and food web modification. PLoS ONE 5(12):e14395. https://doi.org/10.1371/journal.pone.0014395
- Martin, C.W., F.J. Fodrie, K.L. Heck Jr., J. Mattila (2010) Differential habitat use and antipredator response of juvenile roach (Rutilus rutilus) to olfactory and visual cues from multiple predators. Oecologia 162:893-902. https://doi.org/10.1007/s00442-010-1564-x