Julien Martin, Ph.D.
Julien Martin is a Supervisory Biologist based at the Eastern Ecological Science Center.
Julien Martin is a Supervisory Biologist at the US Geological Survey's Eastern Ecological Science Center. He is the capability team manager of the Quantitative Methods and Decision Science team. He obtained a Ph.D. in the department of Wildlife Ecology and Conservation at the University of Florida. He is a courtesy faculty in the Department of Wildlife Ecology and Conservation at the University of Florida. His expertise includes: ecological modeling, population dynamics and the application of decision theory to natural resource management.
Professional Experience
01/2022-Present: Supervisory Biologist at the US Geological Survey (USGS) at the Eastern Ecological Science Center. Laurel, MD.
09/2014-01/2022: Research Wildlife Biologist at the US Geological Survey (USGS) Wetland Aquatic Research Center. Gainesville, FL.
07/2009-09/2014: Research Scientist at the Fish and Wildlife Research Institute/Florida Fish and Wildlife Conservation Commission (FWC), St. Petersburg, FL.
10/2019-present: Courtesy Associate Professor in the Department of Wildlife Ecology and Conservation, University of Florida, Gainesville.
01/2010-10/2019: Courtesy Assistant Professor in the Department of Wildlife Ecology and Conservation, University of Florida, Gainesville.
07/2007-06/2009: Postdoctoral Research Associate at Patuxent Wildlife Research Center (USGS, Laurel, MD).
09/2001-05/2007: Graduate Research Assistant at the Florida Cooperative Fish and Wildlife Research Unit, USGS/Department of Wildlife Ecology and Conservation at the University of Florida, Gainesville, FL, 40 hours/week. Supervisor:
09/2000-09/2001: Graduate Research Assistant at the Centre d’Etudes Biologique de Chize (CEBC), Centre National pour la Recherche Scientifique (CNRS) and French Polar Institute (IPEV), Chize, France.
10/1998-03/2000: Wildlife Field Biologist and environmental advisor in French Subantarctic islands, Centre National pour la Recherche Scientifique (CNRS) and French Polar Institute (IPEV), Kerguelen and Crozet islands, French Southern and Antarctic Lands.
1998: Field biologist for the Irish Fisheries Board, Dublin, Ireland.
Education and Certifications
Ph.D., Wildlife Ecology and Conservation, University of Florida
Science and Products
An expert elicitation process to project the frequency and magnitude of Florida manatee mortality events caused by red tide (Karenia brevis)
Optimal control of an invasive species using a reaction-diffusion model and linear programming
Status and threats analysis for the Florida manatee (Trichechus manatus latirostris), 2016
Expert elicitation, uncertainty, and the value of information in controlling invasive species
Structured decision making as a conservation tool for recovery planning of two endangered salamanders
Influence of manatees' diving on their risk of collision with watercraft
A quantitative framework for estimating risk of collision between marine mammals and boats
Status and threats analysis for the Florida manatee (Trichechus manatus latirostris), 2012
Global change and conservation triage on National Wildlife Refuges
Structured decision making for management of warm-water habitat for manatees. Final report to U.S. Fish and Wildlife Service
Maximizing the social and ecological value of Cape Romain National Wildlife Refuge, South Carolina as the effects of global change processes increase.
Tailoring point counts for inference about avian density: dealing with nondetection and availability
Science and Products
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Filter Total Items: 47
An expert elicitation process to project the frequency and magnitude of Florida manatee mortality events caused by red tide (Karenia brevis)
Red tides (blooms of the harmful alga Karenia brevis) are one of the major sources of mortality for the Florida manatee (Trichechus manatus latirostris), especially in southwest Florida. It has been hypothesized that the frequency and severity of red tides may increase in the future because of global climate change and other factors. To improve our ecological forecast for the effects of red tidesAuthorsJulien Martin, Michael C. Runge, Leanne J. Flewelling, Charles J. Deutsch, Jan H. LandsbergOptimal control of an invasive species using a reaction-diffusion model and linear programming
Managing an invasive species is particularly challenging as little is generally known about the species’ biological characteristics in its new habitat. In practice, removal of individuals often starts before the species is studied to provide the information that will later improve control. Therefore, the locations and the amount of control have to be determined in the face of great uncertainty aboAuthorsMathieu Bonneau, Fred A. Johnson, Brian J. Smith, Christina M. Romagosa, Julien Martin, Frank J. MazzottiStatus and threats analysis for the Florida manatee (Trichechus manatus latirostris), 2016
Trichechus manatus (West Indian manatee), especially T. m. latirostris, the Florida subspecies, has been the focus of conservation efforts and extensive research since its listing under the Endangered Species Act of 1973. To determine the status of, and severity of threats to, the Florida manatee, a comprehensive revision and update of the manatee Core Biological Model was completed and used to peAuthorsMichael C. Runge, Carol A. Sanders-Reed, Catherine A. Langtimm, Jeffrey A. Hostetler, Julien Martin, Charles J. Deutsch, Leslie I. Ward-Geiger, Gary L. MahonExpert elicitation, uncertainty, and the value of information in controlling invasive species
We illustrate the utility of expert elicitation, explicit recognition of uncertainty, and the value of information for directing management and research efforts for invasive species, using tegu lizards (Salvator merianae) in southern Florida as a case study. We posited a post-birth pulse, matrix model in which four age classes of tegus are recognized: hatchlings, 1 year-old, 2 year-olds, and 3 + yAuthorsFred A. Johnson, Brian J. Smith, Mathieu Bonneau, Julien Martin, Christina Romagosa, Frank J. Mazzotti, J. Hardin Waddle, Robert Reed, Jennifer Kettevrlin Eckles, Laurie J. VittStructured decision making as a conservation tool for recovery planning of two endangered salamanders
At least one-third of all amphibian species face the threat of extinction, and current amphibian extinction rates are four orders of magnitude greater than background rates. Preventing extirpation often requires both ex situ (i.e., conservation breeding programs) and in situ strategies (i.e., protecting natural habitats). Flatwoods salamanders (Ambystoma bishopi and A. cingulatum) are protected unAuthorsKaty O'Donnell, Arianne F Messerman, William J. Barichivich, Raymond D. Semlitsch, Thomas A. Gorman, Harold G Mitchell, Nathan Allan, Dante B. Fenolio, Adam Green, Fred A. Johnson, Allison Keever, Mark Mandica, Julien Martin, Jana Mott, Terry Peacock, Joseph Reinman, Stephanie S. Romañach, Greg Titus, Conor P. McGowan, Susan C. WallsInfluence of manatees' diving on their risk of collision with watercraft
Watercraft pose a threat to endangered Florida manatees (Trichechus manatus latirostris). Mortality from watercraft collisions has adversely impacted the manatee population’s growth rate, therefore reducing this threat is an important management goal. To assess factors that contribute to the risk of watercraft strikes to manatees, we studied the diving behavior of nine manatees carrying GPS tags aAuthorsHolly H. Edwards, Julien Martin, Charles J. Deutsch, Robert G Muller, Stacie M. Koslovsky, Alexander J. Smith, Margie E. BarlasA quantitative framework for estimating risk of collision between marine mammals and boats
Speed regulations of watercraft in protected areas are designed to reduce lethal collisions with wildlife but can have economic consequences. We present a quantitative framework for investigating the risk of deadly collisions between boats and wildlife. We apply encounter rate theory to demonstrate how marine mammal-boat encounter rate can be used to predict the expected number of deaths associateAuthorsJulien Martin, Quentin Sabatier, Timothy A. Gowan, Christophe Giraud, Eliezer Gurarie, Scott Calleson, Joel G. Ortega-Ortiz, Charles J. Deutsch, Athena Rycyk, Stacie M. KoslovskyStatus and threats analysis for the Florida manatee (Trichechus manatus latirostris), 2012
The endangered West Indian manatee (Trichechus manatus), especially the Florida subspecies (T. m. latirostris), has been the focus of conservation efforts and extensive research since its listing under the Endangered Species Act. On the basis of the best information available as of December 2012, the threats facing the Florida manatee were determined to be less severe than previously thought, eithAuthorsMichael C. Runge, Catherine A. Langtimm, Julien Martin, Christopher J. FonnesbeckGlobal change and conservation triage on National Wildlife Refuges
National Wildlife Refuges (NWRs) in the United States play an important role in the adaptation of social-ecological systems to climate change, land-use change, and other global-change processes. Coastal refuges are already experiencing threats from sea-level rise and other change processes that are largely beyond their ability to influence, while at the same time facing tighter budgets and reducedAuthorsFred A. Johnson, Mitchell J. Eaton, Gerard McMahon, Raye Nilius, Mike Bryant, Dave Case, Julien Martin, Nathan J. Wood, Laura TaylorStructured decision making for management of warm-water habitat for manatees. Final report to U.S. Fish and Wildlife Service
No abstract available.AuthorsMichael Kosempa, Julien Martin, Fred A. Johnson, Ron Mezich, Brad Stith, Charles J. Deutsch, Michelle Masi, Holly H. EdwardsMaximizing the social and ecological value of Cape Romain National Wildlife Refuge, South Carolina as the effects of global change processes increase.
Coastal ecosystems in the eastern U.S. have been severely altered by processes associated with human development, including drainage of coastal wetlands, changes in hydrology that alter sediment and freshwater delivery to the coast, land clearing, agricultural and forestry activity, and the construction of seawalls and other structures that “harden” the coast. Sea-level rise and the changing frequAuthorsRaye Nilius, Sarah Dawsey, Mitchell J. Eaton, Julien Martin, Stephanie S. Romañach, Suzanne Baird, Michael Bryant, David J. Case, Fred A. Johnson, Gerard McMahon, Nancy Pau, Elizabeth Pienaar, Mary Ratnaswamy, Steven Seibert, Pamela Wingrove, Nathan J. WoodTailoring point counts for inference about avian density: dealing with nondetection and availability
Point counts are commonly used for bird surveys, but interpretation is ambiguous unless there is an accounting for the imperfect detection of individuals. We show how repeated point counts, supplemented by observation distances, can account for two aspects of the counting process: (1) detection of birds conditional on being available for observation and (2) the availability of birds for detectionAuthorsFred A. Johnson, Robert M. Dorazio, Traci D. Castellón, Julien Martin, Jay O. Garcia, James D. Nichols - Software
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