Building artificial seagrass units

Senior Ja’Kaila Jefferson is getting to work early on her senior thesis examining the impacts of habitat density on pipefish, Syngnathus scovelli, copepod feeding preference.

The Indian River Lagoon (IRL) has faced declining seagrass density and seagrass loss due to water quality issues and algal blooms. Dr. Krejci’s previous research determined a switch in pipefish prey items in field samples from the IRL between 100% and 50% density seahorses beds, and it was unclear if the switch was due to changes in prey abundance or pipefish preference. This study will help isolate how habitat density influences feeding.

The artificial seagrass units (ASU) are modeled after shoal grass, Halodule wrightii, and are made of 0.2 mm x 15 cm green ribbon Ja’Kaila is constructing three densities of seagrass shoots based off of field densities from St. Johns River Water Management District seagrass surveys (around 3,000 shoots per m2 for 100% density). She’ll also be examining 50%, 25% and 0% seagrass coverage.

The first step will be running pilot studies of the ASU and copepods without pipefish to ensure 100% recovery of copepods is possible. Pipefish will be field collected once we receive our FWC permit in Spring semester to begin the feeding trials.

Way to go Ja’Kaila using your time over winter break! We have no doubt she will have a fantastic senior thesis to present in April.

Winter Break data fun…

This winter break Dr. Krejci is working on data entry and analysis from three continuing educational projects in Introduction to Environmental Science. Learn more about these projects here: Educational Research. The results from summer and fall semesters are being processed for presentations in Spring 2020, proposals and manuscripts. There’s nothing more exciting than seeing the positive impacts of educational interventions on student success!


Examining microplastics in estuarine zooplankton samples

Final grades for Fall 2019 have been submitted, and while the courses may be over the research continues on. Dr. Krejci was asked to contribute to a proposal seeking to develop new FTIR technologies. Zooplankton samples collected from the Gamble Rogers State Park in the Matanzas/Halifax River have shown high levels of microplastic filaments. In one milliliter of preserved zooplankton, there can be over 5 threads of filaments, some covered in biofouling.

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General Ecology- Cross Island barrier hike

The last few lectures cover coastal and aquatic ecosystems, which were surrounded with here in Florida. Rather than a traditional lecture, we used our lab time to hike Ponce Preserve and discuss Florida coastal ecology from the beach, to the hammock and lagoon.

Senior thesis presentations

The Aquatic Research Lab presented two senior thesis talks today:

Jehmia Williams- “Determining Spatial and Temporal Water Quality Changes in the Halifax River Lagoon”.

Jehmia’s research required managing a 10,000 row data set, learning about Python coding to remove unwanted data, and running/interpreting Principal Component Analysis (PCA). Jehmia did excellent in follow up questions today on data normalization and mitigating nutrient pollution to the central HRL.

Alyssa Stubbs (coauthor Ja’Kaila Jefferson)- “Benthic and Pelagic Copepod Feeding Preferences of Dwarf Seahorses, Hippocampus zosterae” 

Alyssa and Ja’Kaila have been maintaining live algal and copepod cultures in the lab to support this research, a very challenging task! Alyssa hand picked individual live copepods under the microscope for her feeding trials, with a single trial taking four hours to complete. Her data analysis required coding the maximum likelihood equation in excel, running iterations to determine her proportion values, and running a chi-squared analysis to compare the feeding preferences between prey types. Alyssa confidently answered follow up questions on her statistical analysis and methodology.

It was a proud day to see a years worth of literature reviews, experimental design and research culminating in two outstanding senior presentations! These quantitative studies highlight the strong data science talents of a Bethune-Cookman students from the College of Science, Engineering and Mathematics, preparing our students for competitive 21st century careers!

General Ecology-Macro plastics Lab

Dr. Krejci’s General Ecology course at a Bethune-Cookman Univeristy completed the laboratory analysis of macroplastics collected from Tom Renick and Sun Splash Parks in Daytona Beach, FL.

Macroplastics were collected by sieving around 3-gallons of sand. The samples were sorted in the lab into the categories of natural material, hard plastic, wrappers, styrofoam, cigarette butts, rope, and others. All items were counted and weighed.

Next weeks students will learn how to analyze the ghost crab hole density and size compared to the amount of macroplastics.

ShORE Symposium 2019


Prepare yourself for posts from the Aquatic Research Lab today, as we attend the ShORE Symposium 2019 hosted by Daytona State College, Marine Discovery Center, and the Atlantic Center for the Arts.

This free annual symposium provides a forum for high school students, undergraduates and scientists to share their research and create greater public awareness of issues impacting the Indian River Lagoon and it’s watershed.

Follow the link here to learn more.  See the full agenda of today’s events: ShORE 2019_Draft AgendaFixed

This year undergraduate senior, Jehmia Williams, will be presenting an oral presentation titled “Determining Spatial and Temporal Water Quality Changes in the Halifax River Lagoon”.

Undergraduate seniors, Alyssa Stubbs and Ja’Kaila Jefferson, will be presenting their poster titlied, “Benthic and Pelagic Copepod Feeding Preferences of Dwarf Seahorses, Hippocampus zosterae” and

Undergraduate sophomore, Lauren Albury will present her poster “Zooplankton Density in Dragline Ditch Marsh Sites Compared to Natural Waterways”

These projects are the culmination of over a year of hard work from these women scientists!

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Guest Lecture- New Smyrna Beach Garden Club

Yesterday Dr. Krejci, Dr. Reiter and Dr. Cho has the pleasure of providing guest lectures on environmental science topics for a course offered by the New Smyrna Beach Garden Club.

The lady-dominated club offers a twice-a-year course for its members, called the Environmental School, where they can learn about local, national and international environmental issues.

It’s an absolutely fantastic group and quite commendable that they are spending their free time keeping up to date with these important issues!

B-CU professors will return to the group in January for another week.

Bethune-Cookman hosts Daytona Regional Chamber of Commerce’s seminar on Resilience

Dr. Krejci and her students were invited to hear Dr. Julie Nesheiwat, Florida’s Chief Resilience Officer, Ginger Adair, Director of Volusia County Environmental Management, and Jenifer Rupert, East Central Florida Regional Planning Council, speak at B-CU about Florida’s readiness for climate change.

Sophomore Lauren Albury was able to learn about the economic impacts of climate change along Florida’s East coast and the proactive approaches to preparing for sea level rise.

Overall it was a great opportunity for networking and to ask questions about local, regional and state environmental policy. Thanks to B-CU’s Division of Institutional Advancement for including the Aquatic Research Lab!