People
About Me
My research focuses on concepts and processes related to population and ecosystem dynamics, food web and habitat interactions, and fisheries management. These concepts are applied to understand how fisheries resources and marine ecosystems respond to fishing and environmental change. To that end, I develop mechanistic and empirical models that account for environmental drivers, trophic dynamics, habitat interactions, and policy. An important contribution of my work is the development of trophic-dynamic models and spatially explicit analyses to inform fisheries assessment and management in the Gulf of Mexico and mid-Atlantic regions. This highlights the need to develop ecosystem-based approaches that complement the existing single-species assessment and management framework, thereby building upon the strengths of both approaches. The overall goal of my research is to develop a better understanding of fisheries ecosystems and provide tools (i.e. models) that enable managers, scientists, and stakeholders to become better stewards of our shared natural resources. The models I develop are used to improve population assessments, screen policy options for unintended consequences, prioritize research, and calculate new management reference points that account for ecosystem interactions and the uncertainty therein. This work aims to bridge the gap between ecosystem science, stock assessment, and management, while also advancing ecological theories and concepts.
Current Students and Post Docs
Liam Kehoe
Phd Student, Fisheries and Aquatic Sciences
My PhD research will explore the use of genetics to better understand population dynamics. I will be utilizing simulation and field studies to investigate genetic tagging and close-kin mark-recapture approaches, with a focus on South Atlantic red snapper.
Megan Siemann
PhD Student, Interdiscplinary Ecology
Trevor Kirkland
MS Student, Fisheries and Aquatic Sciences
My project focuses on benthic invertebrate composition in relation to oyster reef health in the Suwannee Sound to inform restoration and ecosystem modeling. The project is assessing invert community abundance and diversity across gradients in oyster abundance, salinity, and sediment types.
Shanae Allen
PhD Student, Fisheries and Aquatic Sciences
My research is focused on optimal multi-species survey designs and estimation methods to improve reef fish management.
Past Students and Post-docs
2022 - Dr. Holden Harris, post-doctoral associate; to Assistant Scientist, University of Miami/NOAA Integrated Ecosystem Assessment program.
2022 - Liam Kehoe, MS Fisheries and Aquatic Sciences to PhD assistantship at UF.
2022 - Daniel Vilas Gonzalez, PhD Fisheries and Aquatic Sciences to post-doctoral fellow in the Punt Lab at UW.
2022 - Dylan Sinnickson, PhD Fisheries and Aquatic Sciences to post-doctoral position in Nathan Dorn's lab at FIU.
Opportunities
We hope to recruit postdoctoral associates and students with broad interests in marine ecology, ecosystem modeling, fisheries stock assessment, food web ecology, species distribution modeling, applied mathematics, and fisheries management. If you have experience in these areas or are interested in learning and pursuing research using these methods, please contact me anytime. Open opportunities will be listed below.
Postdoctoral Associate in Marine Ecosystem Modeling (posted 1/24/2024)
Position: Postdoctoral Associate in Marine Ecosystem Modeling
Location: Hybrid-remote at University of Florida, Gainesville, FL
Salary: $50,000-$60,000, commensurate with experience
Apply By: Open until filled
Start Date: As soon as possible
Direct Link: https://explore.jobs.ufl.edu/en-us/job/530061
Description: We are seeking a highly motivated post-doctoral researcher to develop ecosystem models and analyses to support fisheries management decisions. Join a growing lab, where we develop advanced population and ecosystem models to address real-world challenges in fisheries and natural resource management. Our work is highly quantitative and applied, and seeks to understand how fish stocks and marine ecosystems respond to fishing and environmental change. In doing so, we aim to bridge the gap between ecosystem science, stock assessment, and management, while also advancing ecological theories and concepts. We hope to recruit postdoctoral associates and students with broad interests in marine ecology, ecosystem modeling, fisheries stock assessment, food web ecology, species distribution modeling, applied mathematics, and fisheries management.
The postdoctoral associate will have the opportunity to work on one or more high-profile projects, including: assessing ecosystem impacts of red tides on the West Florida Shelf; developing spatially explicit models to support management of Atlantic menhaden; investigating declines in reef fish abundance in the U.S. South Atlantic region; and coupling marine ecosystem models with ocean climate models. The successful candidate will grow their professional network by working within a diverse, multidisciplinary group of collaborators consisting of marine ecosystem modelers, ecologists, stock assessment scientists, physical oceanographers, biogeochemical modelers, fisheries monitoring program leaders, federal and state fisheries managers, and commercial/recreational fishery stakeholders. The postdoctoral associate will also have the opportunity to help recruit and mentor graduate students. Funding is available for 5 years.
Responsibilities: We invite applicants for a full-time postdoctoral associate to be held at the University of Florida’s Nature Coast Biological Station, with offices located on UF’s main campus in Gainesville and on the Gulf of Mexico in Cedar Key. Hybrid work locations can be accommodated. Responsibilities of the postdoctoral associate may include, but are not limited to, analyzing large datasets on fish, habitat, and water quality; updating and maintaining existing ecosystem models; developing new models and statistical analyses; developing web applications (rShiny); maintaining code through Github; presenting results at management meetings and professional conferences; mentoring graduate students; data management; and preparing scientific publications, grant reports, and outreach materials.
Minimum Qualifications:
A Doctorate degree (PhD) in an environmental science such as marine science, fisheries, ecology, oceanography, or related fields.
Interest in fisheries ecology, marine ecosystem modeling, species distribution modeling, and mathematical modeling with applications to natural resource management.
Ability to work both independently and collaboratively to meet project deliverables.
Must be proficient in R.
Written and oral communication skills, demonstrated by publications in peer-reviewed journals and presentations at professional conferences.
A commitment to foster inclusion and working relationships with colleagues from diverse backgrounds, cultures, nationalities, and identities.
Preferred Qualifications:
Knowledge and experience with ecosystem and food web models, fish population dynamic models and stock assessment, species distribution models, and geospatial analysis of large fisheries and environmental datasets
Experience working in collaborative, multidisciplinary projects and interacting with resource managers.
Experience with the Ecopath and Ecosim software is preferred.
Experience developing R shiny apps and open science tools (GitHub).
Experience in linear and non-linear modeling (GLMs, GAMs), spatial-temporal data analysis, and analysis of gridded spatial data.
Familiarity with the Gulf of Mexico marine ecosystem.
Experience in project management and leading interdisciplinary research teams.
Salary: Salary is commensurate with experience, with annual increases each year for satisfactory performance. Paid leave is accrued at a rate of 5 hours bi-weekly for vacation, sickness, or injury. Benefits include optional retirement, health, dental, vision, and disability insurance.
Start Date: Negotiable, as soon as possible.
Application Requirements: To apply, please provide a cover letter, CV, and contact information of three references. Applications will be accepted and reviewed as they are received, until the position is filled. For additional questions please email David Chagaris, dchagaris@ufl.edu.
MS/PhD Graduate Student Assistant in Climate and Fisheries Modeling (closed 3/1/2024)
Position: MS or PhD Graduate Assistant – climate and fisheries
Location: University of Florida, Gainesville, FL
Salary: $26,000/yr for MS; $32,000 for PhD, plus tuition and benefits
Apply By: closed 3/1/2024
Start Date: Fall 2024
Lab Description: We are seeking highly motivated graduate research assistants to study climate impacts on fisheries at the University of Florida. Here, we develop advanced population and ecosystem models to address real-world challenges in fisheries and natural resource management. Our work is highly quantitative and applied, and seeks to understand how fisheries resources and marine ecosystems respond to fishing and environmental change. In doing so, we aim to bridge the gap between ecosystem science, stock assessment, and management, while also advancing ecological theories and concepts. As such, we hope to recruit students with broad interests in ecosystem modeling, marine ecology, fisheries stock assessment, food web ecology, species distribution modeling, and fisheries management.
Position: This current opportunity is open to prospective MS and PhD students as part of a small cohort (2 students, 1 post-doc) developing applied ecosystem models. The graduate student assistant will work on one or more projects that share an overarching goal to inform ecosystem-based fisheries management by developing climate-ready ecosystem models for the Gulf of Mexico and Southeast U.S. The student will receive training in marine ecosystem modeling, link existing ecosystem models to ocean climate forecasts, and evaluate fisheries management strategies under alternative climate scenarios. The student will be advised by Dr. David Chagaris and collaborate with a diverse team of scientists from NOAA and UF. Funding is available for two student assistantships and is provided through two recent NOAA fisheries climate initiatives.
Minimum Qualifications: For MS student, a BS degree in an environmental science, such as biology, ecology, ecology, oceanography, or related field with a GPA of at least 3.0 (on a 4.0 system). Applicants for the PhD assistantship must have an MS degree (or equivalent) in the same or related fields, and a GPA of at least 3.0 (on a 4.0 system).
Preferred Qualifications:
· Knowledge and experience with ecosystem and food web models, fish population dynamic models and stock assessment, species distribution models, and geospatial analysis of large fisheries and environmental datasets
· Strong written and oral communication skills, demonstrated by publications in peer-reviewed journals and presentations at professional conferences.
· Experience with the Ecopath with Ecosim ecosystem modeling software package.
· Proficient in R statistical computing software.
· Experience working in collaborative, multidisciplinary projects, and leading research projects.
Salary: Annual salary is $26,000 for MS and $32,000 for PhD, plus tuition and benefits, including GatorGradCare health care plan, paid leave (5 days/per semester), and a voluntary retirement programs.
Start Date: Fall 2024 semester
Application Requirements: Please submit a letter of interest, resume or CV, unofficial transcripts and contact information of three references to David Chagaris, dchagaris@ufl.edu. Applications will be accepted and reviewed as they are received, until the position is filled.