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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

Filter Total Items: 43

Range-wide population projections for Northern Red-Bellied Cooters (Pseudemys rubriventris)

Northern Red-Bellied Cooters (Pseudemys rubriventris) have a disjunct distribution with a relictual population in southeastern Massachusetts and a larger range across the mid-Atlantic United States. The relictual population is currently listed with protections under the U.S. Endangered Species Act but the status of the population in the remainder of the species' range has not been assessed, and th
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Ecosystems Mission Area, Wetland and Aquatic Research Center

Open removal models with temporary emigration and population dynamics to inform invasive animal management

Removal sampling data are the primary source of monitoring information for many populations (e.g., invasive species, fisheries). Population dynamics, temporary emigration, and imperfect detection are common sources of variation in monitoring data and are key parameters for informing management. We developed two open robust-design removal models for simultaneously modeling population dynamics, temp
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Ecosystems Mission Area, Biological Threats and Invasive Species Research Program, Fort Collins Science Center, Wetland and Aquatic Research Center

An invasive prey provides long-lasting silver spoon effects for an endangered predator

The natal environment can have long-term fitness consequences for individuals, particularly via ‘silver spoon’ or ‘environmental matching’ effects. Invasive species could alter natal effects on native species by changing species interactions, but this potential remains unknown. Using 17 years of data on 2588 individuals across the entire US breeding range of the endangered snail kite (Rostrhamus s
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Ecosystems Mission Area, Wetland and Aquatic Research Center

Evaluating the effect of expert elicitation techniques on population status assessment in the face of large uncertainty

Population projection models are important tools for conservation and management. They are often used for population status assessments, for threat analyses, and to predict the consequences of conservation actions. Although conservation decisions should be informed by science, critical decisions are often made with very little information to support decision-making. Conversely, postponing decision
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Ecosystems Mission Area, Patuxent Wildlife Research Center, Eastern Ecological Science Center, Wetland and Aquatic Research Center

SiteOpt: An open-source R-package for site selection and portfolio optimization

Conservation planning involves identifying and selecting actions to best achieve objectives for managing natural, social and cultural resources. Conservation problems are often high dimensional when specified as combinatorial or portfolio problems and when multiple competing objectives are considered at varying spatial and temporal scales. Although analytical techniques such as modern portfolio th
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Ecosystems Mission Area, Climate Adaptation Science Centers, Wetland and Aquatic Research Center

Monitoring abundance of aggregated animals (Florida manatees) using an unmanned aerial system (UAS)

Imperfect detection is an important problem when counting wildlife, but new technologies such as unmanned aerial systems (UAS) can help overcome this obstacle. We used data collected by a UAS and a Bayesian closed capture-mark-recapture model to estimate abundance and distribution while accounting for imperfect detection of aggregated Florida manatees (Trichechus manatus latirostris) at thermal re
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Ecosystems Mission Area, Wetland and Aquatic Research Center

Cape Romain partnership for coastal protection

This final report summarizes activities, outcomes, and lessons learned from a 3-year project titled “Climate Change Adaptation for Coastal National Wildlife Refuges” with the Cape Romain National Wildlife Refuge (NWR) and local partners in the surrounding South Carolina Lowcountry. The Lowcountry is classified as the 10-county area encompassing the coastal plain of South Carolina (this report spec
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Ecosystems Mission Area, Climate Adaptation Science Centers, Wetland and Aquatic Research Center

A hidden Markov model for estimating age-specific survival when age and size are uncertain

Estimates of age-specific survival probabilities are needed for age-structured population models and to inform conservation decisions. However, determining the age of individuals in wildlife populations is often problematic. We present a hidden Markov model for estimating age-specific survival from capture–recapture or capture–recapture–recovery data when age is unknown and indicators of age, such
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Ecosystems Mission Area, Wetland and Aquatic Research Center

Optimal allocation of law enforcement patrol effort to mitigate poaching activities

Poaching is a global problem causing the decline of species worldwide. Optimizing the efficiency of ranger patrols to deter poaching activity at the lowest possible cost is crucial for protecting species with limited resources. We applied decision analysis and spatial optimization algorithms to allocate efforts of ranger patrols throughout a national park. Our objective was to mitigate poaching ac
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Ecosystems Mission Area, Wetland and Aquatic Research Center

Reconstructing population dynamics of a threatened marine mammal using multiple data sets

Models of marine mammal population dynamics have been used extensively to predict abundance. A less common application of these models is to reconstruct historical population dynamics, filling in gaps in observation data by integrating information from multiple sources. We developed an integrated population model for the Florida manatee (Trichechus manatus latirostris) to reconstruct its populatio
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Ecosystems Mission Area, Eastern Ecological Science Center, Patuxent Wildlife Research Center, Wetland and Aquatic Research Center

Modeling structural mechanics of oyster reef self-organization including environmental constraints and community interactions

Self-organization is a process of establishing and reinforcing local structures through feedbacks between internal population dynamics and external factors. In reef-building systems, substrate is collectively engineered by individuals that also occupy it and compete for space. Reefs are constrained spatially by the physical environment, and by mortality, which reduces production but exposes substr
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Ecosystems Mission Area, Wetland and Aquatic Research Center

Spatial conservation planning under uncertainty using modern portfolio theory and nash bargaining solution

In recent years, researchers from interdisciplinary teams involving ecologists, economists and operations re- searchers collaborated to provide decision support tools to address the challenges of preserving biodiversity by optimizing the design of reserves. The goal of this paper is to further advance this area of research and provide new solutions to solve complex Spatial Conservation Planning (
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Ecosystems Mission Area, Climate Adaptation Science Centers, Wetland and Aquatic Research Center
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two photos of same coral. Left coral mostly covered in live tissue, with dead section. Right photo: dead coral covered in algae

Research in response to Florida’s emerging coral disease

Coral reefs are both ecologically and economically important, serving as nurseries for fisheries, protecting the coastline from storm surges, and generating income from tourism. Since 2014, a wide variety of corals have been dying from unexplained causes throughout South Florida with mortalities ranging from North Miami to the Florida Keys.
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Ecosystems Mission Area, Biological Threats and Invasive Species Research Program, Fish & Wildlife Disease (unpublished), National Wildlife Health Center
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Research in response to Florida’s emerging coral disease

Coral reefs are both ecologically and economically important, serving as nurseries for fisheries, protecting the coastline from storm surges, and generating income from tourism. Since 2014, a wide variety of corals have been dying from unexplained causes throughout South Florida with mortalities ranging from North Miami to the Florida Keys.
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Aerial photograph looking west along Dauphin Island, Alabama, taken in September 2016.

Coastal Resource Evaluation for Management Application (CREMA)

Coastal environments are dynamic systems that provide high ecological, economical, recreational, and cultural value. Managing coastal systems requires a comprehensive understanding of the complex interactions between geological and ecological processes, as well as the ability to predict both the near-term and long-term impacts of storms and sea-level rise. The Coastal Resource Evaluation for...
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Natural Hazards Mission Area, Coastal and Marine Hazards and Resources Program, St. Petersburg Coastal and Marine Science Center
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Coastal Resource Evaluation for Management Application (CREMA)

Coastal environments are dynamic systems that provide high ecological, economical, recreational, and cultural value. Managing coastal systems requires a comprehensive understanding of the complex interactions between geological and ecological processes, as well as the ability to predict both the near-term and long-term impacts of storms and sea-level rise. The Coastal Resource Evaluation for...
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USGS science for a changing world logo

Real-time Coastal Salinity Index for monitoring coastal drought and ecological response to changing salinity values

Many coastal areas are experiencing departures from normal conditions due to changing land use and climate patterns, including increased frequency, severity, or duration of floods and droughts, in some cases combinations of the two. To address these issues, the U.S. Geological Survey developed the Coastal Salinity Index (CSI) to identify and communicate fluctuating salinity conditions due to such
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Community for Data Integration (CDI)
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Real-time Coastal Salinity Index for monitoring coastal drought and ecological response to changing salinity values

Many coastal areas are experiencing departures from normal conditions due to changing land use and climate patterns, including increased frequency, severity, or duration of floods and droughts, in some cases combinations of the two. To address these issues, the U.S. Geological Survey developed the Coastal Salinity Index (CSI) to identify and communicate fluctuating salinity conditions due to such
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Manatee swims in a Florida spring

Population Ecology of Florida Manatees

USGS is working with partners to understand how the federally protected Florida manatee population changes over time and responds to threats.
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Ecosystems Mission Area, Species Management Research Program, Wetland and Aquatic Research Center
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Population Ecology of Florida Manatees

USGS is working with partners to understand how the federally protected Florida manatee population changes over time and responds to threats.
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North Atlantic Right Whale

Quantitative Framework to Model Risk of Collisions between Marine Wildlife and Boats

Collisons between wildlife and vehicles threaten many species, and can lead to human loss of life, injuries, and loss of property. USGS is developing models to help evaluate the effectiveness of wildlife protection zones and optimize the design of these protected areas.
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Ecosystems Mission Area, Species Management Research Program, Wetland and Aquatic Research Center
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Quantitative Framework to Model Risk of Collisions between Marine Wildlife and Boats

Collisons between wildlife and vehicles threaten many species, and can lead to human loss of life, injuries, and loss of property. USGS is developing models to help evaluate the effectiveness of wildlife protection zones and optimize the design of these protected areas.
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Bulls Island, Cape Romain National Wildlife Refuge

Climate Change Adaptation for Coastal National Wildlife Refuges

National Wildlife Refuges provide habitat for important fish and wildlife species and services that benefit coastal communities, like storm-surge protection. USGS scientists are helping coastal refuges plan for and adapt to sea-level rise.
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Ecosystems Mission Area, Land Management Research Program, Species Management Research Program, Wetland and Aquatic Research Center
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Climate Change Adaptation for Coastal National Wildlife Refuges

National Wildlife Refuges provide habitat for important fish and wildlife species and services that benefit coastal communities, like storm-surge protection. USGS scientists are helping coastal refuges plan for and adapt to sea-level rise.
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Argentine black-and-white tegu (Tupinambis merianae)

A Structured Decision-Making Framework for Controlling, Monitoring, and Containment of Invasive Species through Trapping: An Application to the Argentine Black and White Tegu

USGS is applying decision analysis to identify cost-effective methods for controlling invasive species like the Argentine black and white tegu.
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Ecosystems Mission Area, Biological Threats and Invasive Species Research Program, Species Management Research Program, Wetland and Aquatic Research Center
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A Structured Decision-Making Framework for Controlling, Monitoring, and Containment of Invasive Species through Trapping: An Application to the Argentine Black and White Tegu

USGS is applying decision analysis to identify cost-effective methods for controlling invasive species like the Argentine black and white tegu.
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Melaleuca

Decision Analysis to Help Improve the Effectiveness of Invasive Plants Management

Melaleuca is an invasive tree that is highly problematic in the Everglades, threatening native wildlife and habitat. USGS is helping to improve management strategies for the invasive plant.
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Ecosystems Mission Area, Biological Threats and Invasive Species Research Program, Land Management Research Program, Wetland and Aquatic Research Center
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Decision Analysis to Help Improve the Effectiveness of Invasive Plants Management

Melaleuca is an invasive tree that is highly problematic in the Everglades, threatening native wildlife and habitat. USGS is helping to improve management strategies for the invasive plant.
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Refuge managers must decide when and where to acquire or protect new land/habitat

Global Change and Conservation Triage on National Wildlife Refuges

As custodians of ecological goods and services valued by society, coastal National Wildlife Refuges (NWRs) have an especially important role to play in helping socio-ecological systems adapt to global-change processes.
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Ecosystems Mission Area, Land Management Research Program, Wetland and Aquatic Research Center
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Global Change and Conservation Triage on National Wildlife Refuges

As custodians of ecological goods and services valued by society, coastal National Wildlife Refuges (NWRs) have an especially important role to play in helping socio-ecological systems adapt to global-change processes.
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Researchers capture a Burmese python in the Everglades

Optimal Control Strategies for Invasive Exotics in South Florida

The establishment and proliferation of exotic plants and animals can interfere with native ecological processes and can cause severe stress to sensitive ecosystems.
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Ecosystems Mission Area, Biological Threats and Invasive Species Research Program, Wetland and Aquatic Research Center
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Optimal Control Strategies for Invasive Exotics in South Florida

The establishment and proliferation of exotic plants and animals can interfere with native ecological processes and can cause severe stress to sensitive ecosystems.
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Frosted flatwoods salamander

Adaptive Habitat Conservation for Flatwoods Salamanders

USGS scientists investigate adaptive habitat conservation for Flatwoods salamanders.
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Ecosystems Mission Area, Species Management Research Program, Wildlife Program (unpublished), Wetland and Aquatic Research Center
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Adaptive Habitat Conservation for Flatwoods Salamanders

USGS scientists investigate adaptive habitat conservation for Flatwoods salamanders.
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St. Marks National Wildlife Refuge, Florida

Climate Change Adaptation for Coastal National Wildlife Refuges

National Wildlife Refuges (NWRs) along the East Coast of the United States protect habitat for a host of wildlife species, while also offering storm surge protection, improving water quality, supporting nurseries for commercially important fish and shellfish, and providing recreation opportunities for coastal communities. Yet in the last century, coastal ecosystems in the eastern U.S. have been se
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Climate Adaptation Science Centers
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Climate Change Adaptation for Coastal National Wildlife Refuges

National Wildlife Refuges (NWRs) along the East Coast of the United States protect habitat for a host of wildlife species, while also offering storm surge protection, improving water quality, supporting nurseries for commercially important fish and shellfish, and providing recreation opportunities for coastal communities. Yet in the last century, coastal ecosystems in the eastern U.S. have been se
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Expert assessments of hypotheses concerning the etiological agent(s) of Stony Coral Tissue Loss Disease collected during a rapid prototyping project

This dataset is from expert elicitation of a panel of 15 experts with knowledge of stony coral tissue loss disease (SCTLD) and its impacts on coral reefs. We gathered this group of 15 participants with diverse expertise who had previously studied SCTLD including at universities and various government agencies as microbiologists, pathologists, disease ecologists, population ecologists, and coral ex
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Cooperative Research Units

Data for analysis of open removal models with temporary emigration and population dynamics to inform invasive animal management

This data release includes the data and computer code that we produced to fit two open-robust design removal models developed to simultaneously model population dynamics, temporary emigration, and imperfect detection: a random walk linear trend model (estimable without ancillary information), and a 2-age class integrated population model (IPM) that used prior information for age-structured vital r
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Wetland and Aquatic Research Center

Data from: ''Evaluating the effect of expert elicitation techniques on population status assessment in the face of large uncertainty''

The dataset contains estimates (low, estimate, high) of 12 population parameters for the wood turtle (Glyptemys insculpta) from the literature and experts.
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Wetland and Aquatic Research Center

An expert elicitation process to project the frequency and magnitude of Florida manatee mortality events caused by red tide (Karenia brevis)

Table summarizing results from expert elicitation process to project the frequency and magnitude of Florida manatee mortality events caused by red tide (Karenia brevis).
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Wetland and Aquatic Research Center

Code for Rapid prototyping for quantifying belief weights of competing hypotheses about emergent diseases

Code submitted to Journal of Environmental Management and ScienceBase for running Bayesian hierarchical models on a dataset that was collected using expert elicitation of a panel of 15 experts on the etiology of stony coral tissue loss disease and its impacts on coral reefs. The code is for a rapid prototyping method for quantifying belief weights for competing hypotheses about the etiology of dis
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Cooperative Research Units
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Florida Manatees Likely to Persist For At Least 100 Years—US Geological Survey  

Florida’s iconic manatee population is highly likely to endure for the next 100 years, so long as wildlife managers continue to protect the marine...

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Media Inquiries on USGS Manatee Research

We appreciate your interest in USGS' Sirenia Project. To help inform members of the media and public, we have provided relevant publications, reports...

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Science and Products