On Monday, May 21, 2017 the Lapointe HAB Lab presented the findings of the recently released report, "Microbial Source Tracking of Bacterial Pollution in the North Fork of the St. Lucie River" at a special meeting of the Port St. Lucie City Council. Dr. Lapointe, Lynn Wilking, and Rachel Brewton all attended the meeting. Brewton presented the findings of the study and all were on-hand after the presentation to answer questions. WPTV reported on the meeting and the link to their coverage is below.
We are in the process of writing a scientific paper that will examine the biochemistry and nutrient sources supporting different seagrass species within the Indian River Lagoon, Florida. There are seven species of seagrasses reported for the Indian River Lagoon, however of particular interest, is the oligotrophic seagrass, Thalassia testudinum. Often referred to as "turtle grass", Thalassia has the highest light requirement of all seagrasses and is considered to be an indicator of a healthy ecosystem. On the Atlantic coast, Sebastian Inlet was considered to be the northernmost limit of Thalassia, however there is concern that is may be receding to the south. There were reports of locations where Thalassia might still exist in this area, so we took the HBOI Sundance out to investigate. After thoroughly surveying multiple sites, we were unable to confirm any Thalassia in this area currently. We did find abundant populations of Caulerpa prolifera, an alga that resembles Thalassia, but thrives in nutrient rich and low light water. Could these previous reports have mistaken Caulerpa prolifera for Thalassia or has it recently receded and is no longer present at Sebastian Inlet?
On April 29, 2018, Brian conducted a belated birthday dive at Looe Key reef. The wind was less than 4 knots and the seas were calm, however the water was still relatively turbid and green with visibility around 35 ft. Brian collected water samples for nutrient analysis to add to our long-term database. He also observed blooms of the macroalgae Dictyota menstrualis and Liagora ceranoides. The shallow fore reef experienced intense wave action during Hurricane Irma and the coral spur framework had been blown apart exposing fossil remains of elkhorn coral Acropora palmata. This is a reminder that elkhorn coral played a major role in the construction of the spur and groove formation of Looe Key reef over geological time. Currently, greater than 95% of the elkhorn coral at Looe Key is gone, indicating that this reef can no longer keep pace with sea level rise, and would be considered to be a "give up" reef. The HAB Lab has just submitted a research article detailing three decades of Brian's water quality monitoring at Looe Key reef, we look forward to sharing this paper when it is in press.
The North Fork of the St. Lucie River in Port St. Lucie, Florida is impaired for fecal bacteria, nitrogen, phosphorus, and dissolved oxygen. Periodically, the system is closed for recreational use due to high bacteria levels. In order to determine the sources of this problem, the City of Port St. Lucie undertook a Microbial Source Tracking Study in partnership with St. Lucie County and the Florida Department of Environmental Protection. The Lapointe HAB Lab provided analytical assistance of the resulting data. The final report has been submitted to the city for review and the HAB Lab will present the results to the City Council on May 21, 2017.
During the study surface water samples were collected from tributaries of the North Fork, canals draining into the North Fork, and the main stem of the river from White City Park into the St. Lucie Estuary. Water samples were analyzed for molecular markers, chemical tracers, bacterial concentrations, and dissolved nutrients during the 2016 wet season, the 2017 dry season, and a 2017 rain event; nutrients were also sampled once during the 2017 wet season. The data collected during the study indicated a few potential sources of fecal bacteria to the North Fork, such as septic systems, sewer system leaks, and urban runoff. The highest concentrations of wastewater tracers and reactive nitrogen were found in residential canals. The HAB Lab suggested future research and monitoring activities to further hone in on sources contributing to this issue. Link to the report below.
The newest video from Dr. Lapointe's collaboration with the Florida Chamber of Commerce was featured in Florida Politics. This video describes the water quality issues facing the Kissimmee River basin, which extends from Orlando to Lake Okeechobee. Link to the story and video below.
HAB Lab M.S. Student Bret Kaiser defended his thesis, "Relationships between Dissolved Nutrients, Environmental Variables, and Acidification in the Indian River Lagoon". He will graduate in May 2018. Congrats to Bret!
Brewton and Wilking successfully completed the final 2018 Dry Season sampling event in Lee County. Once all the samples have been analyzed, we will begin to assess the data and produce a report for the county. Looking forward to the results of this joint effort between Lee County, Florida Department of Environmental Protection, and the HBOI HAB Lab!
The HAB Lab traveled to St. Augustine to present at the Spring 2018 SEERS meeting.
Dr. Lapointe manned an outreach booth during Florida Springsfest 2018 at Silver Springs State Park. While at Springsfest, Brian got to meet the Creature from the Black Lagoon, Ricou Browning.
The HAB Lab had a big presence at the 2018 Indian River Lagoon Symposium. Brewton, Madio, and Kaiser all gave oral presentations, while Wilking presented a poster.
The HAB Lab research project looking at changes in water quality after widespread fertilizer bans was featured in the TC Palm. This project should be submitted for publication in a scientific journal late this spring.
The Palm Beach Post featured the HAB Lab's newly published paper. The article, authored by Dr. Lapointe, Laura Herren, and Armelle Paule, described water quality in the St. Lucie Estuary and the relationship with wastewater from septic systems. In this research, sucralose was used as a tracer of human wastewater within the system. A link to the article from the Palm Beach Post and the WPTV coverage can be found below.
What does a coral reef look like after a major hurricane? About six weeks post-Irma, Dr. Lapointe dove at Looe Key Sanctuary Preservation Area in the Florida Keys National Marine Sanctuary to find out. At Looe Key reef Brian found fine turbidity in the water, which made it appear cloudy, and high chlorophyll a levels that gave the water a green tinge. There was sediment deposited on the reef biota and many coral heads were split apart. Brian will continue to dive at Looe Key as often as possible to keep a watchful eye on the reef. The lab is hard at work writing up a research article that compiles thirty years of Brian's Looe Key monitoring data, so stay tuned for that near the end of 2018.
Hurricane Irma made landfall in the Lower Florida Keys on September 10, 2017. Irma brought with it some very intense wind, with gusts up to 180 mph, and 20 ft. of storm surge on the windward side of Big Pine Key. In the wake of the storm there was severe physical and biological damage throughout the Florida Keys. Dr. Lapointe's lab on Big Pine Key was flooded, but was not destroyed. The disturbance of large storms, such as Irma, can result in water quality issues, such as increased turbidity and algal blooms, and can have broad ecological effects, including species shifts and habitat loss. In the coming month, Dr. Lapointe, a part-time resident of Big Pine Key since 1983, will be keeping a watchful eye on the health and future trajectory of the unique ecosystems of the Lower Florida Keys.
We are excited to welcome our new M.S. student, Jordan Madio, to Harbor Branch! Jordan completed his B.S. in Environmental Science at Stetson University in 2016. After graduation Jordan worked as a consultant for the City of Sunrise, where he focused on climate change vulnerability analyses. For his thesis, Jordan will be expanding our current research in the North Fork of the St. Lucie River to help understand factors contributing to the system's impairment.
Research Coordinator, Rachel Brewton, presented at the American Fisheries Society Annual Meeting in Tampa, FL on August 22, 2017. The theme of the meeting was Fisheries Ecosystems: Uplands to Oceans. Her talk, "Effects of Land-Based Nutrient Pollution on Coral Reef Ecosystems Revealed By Long-Term Monitoring at Looe Key, Florida" described downstream effects of upstream water management. Other faculty, students, and staff from HBOI-FAU also attended the meeting.
Dr. Lapointe gave the plenary talk at the 8th Annual Florida United Waterfowl Summit in Ocala,FL on August 11, 2017. He discussed downstream effects of Everglades Restoration, such as how nutrient loading can lead to harmful algal blooms and increased loss of living coral.
Recently, Dr. Lapointe and Lab Chemistry Coordinator Lynn Wilking conducted a sampling expedition to collect pelagic Sargassum macroalgae offshore of the lower Florida Keys. Pelagic Sargassum serve as an ecologically important habitat for many marine animals, however excessive beaching of this seaweed has become an increasing nuisance since 2011. Sargassum may also affect the ocean’s biogeochemistry through modulating nutrient cycles and releasing colored dissolved organic matter. However, to date, except for a handful of studies, our knowledge in these areas is only next to nil. In conjunction our collaborator, Dr. Chuanmin Hu, from the University of South Florida we are working to better understand the distribution and abundance of pelagic Sargassum and the linkages with environmental changes in the Intra-Americas Sea and Tropical Atlantic.
Ryther revisited: Nutrient excretions by fishes enhance productivity of pelagic Sargassum in the western North Atlantic Ocean
Dr. Lapointe was invited by the Wildlife Conservation Society to return to Belize, where he conducted seminal research on the effects of nutrient enrichment on coral reefs in the 1980s and early 1990s. During this trip, he and Wildlife Conservation Society staff collected water samples of groundwater and rainfall at Glover's Reef Research Station. Macroalgae were collected at a variety of sites, including Glover's Reef, Curlew Reef, Tobacco Reef, Twin Cays, and Man-O-War Cay (seabird rookery), for elemental and stable isotope analysis. These samples will be compared with the historic samples Dr. Lapointe collected in the 1980s to see of how nutrient content of macroalgae have changed over the last 20 years. These data will help scientists and resource managers better understand the mechanisms causing the ongoing macroalgal blooms plaguing the Belize Barrier Reef Complex. Dr. Lapointe plans to present the results of this restudy in November at the 2017 Gulf and Caribbean Fisheries Institute meeting in Mérida, Yucatan, Mexico. Links to related research in Belize by Dr. Lapointe below.
Macroalgal overgrowth of fringing coral reefs at Discovery Bay, Jamaica: Bottom-up versus top-down control
A comparison of nutrient-limited productivity in macroalgae from a Caribean barrier reef and from a mangrove ecosystem
Dr. Lapointe & Research Coordinator, Rachel Brewton, traveled to the Florida Keys to dive at Looe Key to film an outreach news segment about Looe Key National Marine Sanctuary with Jay Cashmere of WPTV. Dr. Lapointe discussed his long-term monitoring program at Looe Key and changes he has observed on the reef over the last 30 years.
Brian & Rachel stayed at Dr. Lapointe's lab on Big Pine Key during the quick trip and managed to squeeze in a sunset paddle before heading back to Fort Pierce.
Dr. Lapointe presented "Evidence of Wastewater-Driven Eutrophication and Harmful Algal Blooms in the Indian River Lagoon, East-Central, Florida" at the 93rd Florida Annual Meeting and Exposition (FAME) hosted by the Florida Section of the American Chemical Society at the Innisbrook Resort in Palm Harbor, FL.
EVIDENCE OF WASTEWATER-DRIVEN EUTROPHICATION
AND HARMFUL ALGAL BLOOMS IN THE INDIAN RIVER LAGOON, EAST-CENTRAL FLORIDA
Dr. Brian E. Lapointe
ABSTRACT: The Indian River Lagoon (IRL) has experienced problems associated with increasing macroalgal blooms, seagrass epiphytization, and hypoxia/anoxia for decades. Following significant rainfall in Spring 2011 that ended a multi-year drought, a severe “super bloom” of phytoplankton (> 100 µg/L Chl a) developed in the northern IRL. This was followed by a “brown tide” in the northern IRL and Mosquito Lagoon in 2012, which was followed by widespread seagrass die-off and wildlife mortality, including endangered manatees. To better understand the nutrient source(s) and dynamics surrounding these harmful algal blooms (HABs), seawater samples and benthic macroalgae were collected at a network of 20 stations throughout the IRL. High TDN concentrations (up to 152 µM) and TDN:TDP ratios (>100:1) in the poorly flushed northern IRL, Mosquito Lagoon and Banana River segments reflected the accumulation and cycling of N-rich groundwater and surface water inputs that produce P- limitation. Macroalgae d15N values were enriched throughout the IRL (+6.3 o/oo) and similar to values reported for macroalgae from other sewage-polluted coastal waters. Because point-source sewage inputs to the IRL were largely eliminated through the IRL Act of 1990, these results suggest that non-point source N enrichment from septic tanks (300,000-600,000) represents a significant and largely ignored N-source to the IRL. The high degree of sewage N contamination of the IRL, combined with recent HABs, including toxic ecotypes of the red macroalga Gracilaria tikvahiae McLachlan, seagrass loss, and wildlife mortality, indicates a critical need for improved sewage collection and treatment, including nutrient removal.
Studying water quality and harmful algal blooms throughout Florida and the Caribbean.