Spotlight on Affiliate Graduate Student Research at UF/IFAS NCBS

At University of Florida Institute of Food and Agricultural Sciences (UF/IFAS), graduate students play a vital role in advancing research that helps us better understand and protect Florida’s natural resources. Many of these students are affiliate researchers with the Nature Coast Biological Station (NCBS), co-advised by faculty in their home departments and NCBS scientists, creating a collaborative environment that bridges disciplines and connects research to real-world coastal challenges. In celebration of Graduate Student Appreciation Week (April 6 – 10), we’re highlighting a few of these projects led by UF/IFAS graduate students working along Florida’s Nature Coast. From uncovering the chemical defenses that support seagrass resilience to exploring how fish communities respond to habitat connectivity and environmental change, these projects showcase the next generation of scientists tackling complex questions in coastal ecosystems.

Graduate Student Research Project Highlights

Top-Down and Bottom-Up Drivers of Resource Allocation and Secondary Metabolite Production in Thalassia testudinum

Written by Carter Oleckna, Ph.D., School of Forest, Fisheries, and Geomatics Sciences

Advisors: Robert Lamb (UF/IFAS NCBS) and Don Behringer (UF/IFAS SFFGS)

Carter Oleckna in a motorboat, holding the steering handle of the boat with his left hand and adjusting the brim of his cap with his right hand. — *Carter making his way to a field site by boat. Photo credit: Carlos Alves Almeida.*

Seagrass meadows are one of the most important coastal habitats along the Nature Coast, supporting fisheries, stabilizing sediments, improving water quality, and storing carbon. But these ecosystems are under increasing pressure. Climate change, eutrophication, and boating scars all contribute to declining seagrass cover, making it vital to understand how seagrasses cope with stress and what drives their resilience.

My research investigates the chemical defenses that help Thalassia testudinum, or turtle grass, respond to environmental stressors. Seagrasses produce chemical defense compounds known as secondary metabolites that act as defenses against herbivores, pathogens, and harsh environmental conditions. These compounds also help regulate interactions with nutrients, microbes, and other organisms. Seagrasses must allocate secondary metabolite production in a delicate balance between growth and defense, all in the context of shifting environmental conditions such as temperature, nutrients, and herbivory.

*Carter Oleckna, in a wetsuit with snorkeling gear, gives a thumbs-up while in the ocean. Photo credit: Carlos Alves Almeida.*

My dissertation focuses on understanding how top-down and bottom-up forces influence chemical defenses in T. testudinum. I am investigating how seasonal and spatial environmental changes influence growth rates and phenolic production, how different types of herbivores trigger chemical defense responses, and whether providing seagrasses with aromatic amino acids can boost the production of these chemical compounds.

I’m a second year Ph.D. student in the Lamb and Behringer Labs at UF, where my research examines how chemical ecology and resource allocation influence seagrass resilience along Florida’s Gulf Coast. In the long run, this work may also help identify new ways to support healthier and more resilient seagrass meadows throughout the Nature Coast.

Sound and Sight: Linking Habitat Connectivity and Fish Biodiversity in Florida’s Coastal Waters

Written by Finella Campanino, Ph.D., School of Natural Resources and Environment

Advisors: Laura Reynolds (UF/IFAS SWES) and Savanna Barry (UF/IFAS NCBS)

*Finella Campanino snorkeling underwater near marine plants and corals, writing on a clipboard attached to a pole mounted with a camera. Photo credit: Enie Hensel.*

Florida’s coastal ecosystems (e.g., seagrass meadows, mangrove keys, and hard-bottom habitats) form a connected mosaic that supports some of the state’s most iconic and economically important fish species. Yet these habitats are increasingly threatened by development, fragmentation, and habitat loss. Understanding how fish use these areas, and how the connections between them shape biodiversity, is essential for effective management of coastal resources.

My research uses an innovative combination of underwater visual census (UVC) and passive acoustic monitoring (PAM) to study fish communities across the St. Martin’s Marsh Aquatic Preserve. By pairing traditional snorkel-based surveys with underwater sound recordings, I hope to capture both what can be seen and what can be heard; including vocalizing, cryptic, and nighttime-active species often missed by visual surveys.

Every month from March through October 2025, I looked at and listened to the fish communities across seagrass meadows, mangrove keys, and hard-bottom habitats that were either close together or more isolated from one another. I place acoustic recorders (HydroMoths) at these habitats every full moon to document dawn and dusk soundscapes, when many fish produce noises associated with mating, territory, or other communication types.

My dissertation research aims to answer key questions:

How do fish communities differ between seagrass, mangroves, and hard-bottom habitats and across seasons?
Do more connected habitats support greater biodiversity?
Can acoustic monitoring serve as a reliable, low-impact tool for long-term fisheries assessment?

My research supports the St. Martin’s Marsh Aquatic Preserve Management Plan by improving understanding of fish–habitat relationships and evaluating PAM as a potential monitoring method. Beyond advancing science, my research provides research opportunities and training for undergraduate students, contributing to the next generation of marine scientists. By integrating sight and sound, my research expands the toolkit for coastal conservation and offers new insight into how Florida’s underwater habitats sustain vibrant and resilient fish communities.

Fish Communities in a Changing Environment: Exploring the Function of Aquifer Seeps and Springs as Thermal Refuges for Fishes Within the Suwannee River Estuary

Written by Katherine Henning, M.S., School of Forest, Fisheries, and Geomatics Sciences

Advisors: Robert Lamb (UF/IFAS NCBS) and Deb Murie (UF/IFAS SFFGS)

Katherine Henning standing in front of green foliage and holding a large fish. — *Katherine Henning standing in front of mangroves, holding a large Black Drum pulled in a seine net. Photo credit: Robert Lamb.*

Florida’s Nature Coast is undergoing rapid ecological change as tropicalization reshapes its temperate ecosystems, driving shifts in species ranges and increasing the frequency of marine heat waves alongside the region’s characteristic episodic cold snaps. Under these conditions, thermal refuges, areas where temperatures remain relatively stable, can play a critical role in supporting aquatic species. The Nature Coast’s karst geology creates ideal conditions for such refuges, with abundant aquifer springs and seeps supplying groundwater at relatively constant temperatures into coastal rivers and tidal creeks. Despite their ecological importance, however, many of these low-magnitude springs remain unmapped, under-studied, and poorly understood.

Katherine Henning standing in shallow water, surrounded by marsh vegetation. She and another person work together to handle a fishing net. — *Katherine Henning standing in shallow water, surrounded by marsh vegetation. She and another person work together to pull a seine net. Photo credit: Robert Lamb.*

My research investigates these springs and seeps as potential thermal refuges and essential fish habitat within the Suwannee River estuary. Using an integrated approach that combines aerial infrared imagery, GIS based hotspot detection, and in-situ environmental monitoring, I identify thermal anomalies on the landscape and evaluate how their hydrology and temperature regimes vary through time. From August- September of 2025, I conducted standardized seine surveys at 20 paired thermal anomaly and ambient control sites from the mouth of the Suwannee River to the northern border of Waccasassa Bay Preserve. Water quality parameters were measured at each site using a YSI, and HOBO temperature loggers were deployed at selected locations to capture both instantaneous environmental conditions and continuous thermal dynamics.

This research examines how fish assemblages, trophic structure, environmental conditions, and growth vary between thermal anomalies and ambient habitats, across the broader estuarine gradient, and between seasonal extremes. A second field season (January 2025– February 2026) will resample all sites to assess winter assemblages and refine understanding of seasonal habitat use. By coupling GIS analysis, hydrological assessment, and ecological monitoring, this project advances our understanding of how habitat structure and thermal stability influence juvenile sportfish and forage fish communities. The results will support ongoing efforts by state agencies to locate and protect essential fish habitat, guide sportfish management under tropicalizing conditions, and improve knowledge of groundwater–surface water connections within the estuary.

As a second-year master’s student in the Lamb and Murie labs, I aim for this research to contribute both to ecosystem-based fisheries management and to a deeper understanding of how Florida’s coastal habitats can sustain diverse fish communities in a changing future.

Meet our other affiliate graduate students here.

Featured image credit: Enie Hensel