From the FAU Newsdesk: "A study published in the international journal Marine Biology , reveals what’s really killing coral reefs. With 30 years of unique data from Looe Key Reef in the lower Florida Keys, researchers from Florida Atlantic University’s Harbor Branch Oceanographic Institute and collaborators have discovered that the problem of coral bleaching is not just due to a warming planet, but also a planet that is simultaneously being enriched with reactive nitrogen from multiple sources."
Read more at the links below:
"Researchers in Florida have identified the world's largest seaweed bloom, a massive expanse of Sargassum visible from space..."
Read more about Dr. Lapointe's new research paper about Sargassum blooms, published today in Science!
"This summer may shape up to be the worst inundation of sargassum in recent time for Florida, writes columnist Frank Cerabino. Brian LaPointe, a research professor at Florida Atlantic University’s Harbor Branch Oceanographic Institute, likes to talk in terms of the movie Jaws. “We’re going to need a bigger boat,” LaPointe told me Tuesday.
We were not talking about sharks. We were talking about seaweed. ..."
Read more from the Palm Beach Post at the link below.
Caloosahatchee River - North Fort Myers Report presented to Lee County Board of County Commissioners
Dr. Lapointe & Rachel Brewton presented the findings of their 2017-2018 study on factors affecting water quality in the North Fort Myers area in a workshop to the Lee County Board of County Commissioners. Other co-authors on the study included Lynn Wilking & Laura Herren. The study will continue for a second year beginning in August 2019. The year 1 report and a video of the proceedings can be found below.
A new study on the floating, pelagic brown seaweed, Sargassum, was published in Geophysical Research Letters by our University of South Florida (USF) collaborators with HAB Lab members, Brian Lapointe and Rachel Brewton as co-authors. Information regarding what drives the productivity and distribution of Sargassum is becoming more important every year, as blooms continue to worsen globally. The HBOI HAB Lab is continuing to pursue these important questions with our USF and other collaborators.
Field and laboratory experiments are designed to measure Sargassum biomass per area (density), surface reflectance, nutrient contents, and pigment concentrations. An alternative floating algae index-biomass density model is established to link the spectral reflectance to Sargassum biomass density, with a relative uncertainty of ~12%. Monthly mean integrated Sargassum biomass in the Caribbean Sea and central West Atlantic reached at least 4.4 million tons in July 2015. The average %C, %N, and %P per dry weight are 27.16, 1.06, and 0.10, respectively. The mean chlorophyll-a (Chl-a) concentration is ~0.05% of the dry weight. With these parameters, the amounts of nutrients and pigments can be estimated directly from remotely sensed Sargassum biomass. During bloom seasons, Sargassum carbon can account for ~18% of the total particulate organic carbon in the upper water column. This study provides the first quantitative assessment of the overall Sargassum biomass, nutrients, and pigment abundance from remote sensing observations, thus helping to quantify their ecological roles and facilitate management decisions.
Dr. Lapointe presented a session on Nutrient Enrichment as a Factor Driving Macroalgal Blooms on the Belize Barrier Reef Complex (BBRC). The BBRC represents a significant portion of the world’s second largest coral reef complex and encompassing a World Heritage site, the Belize Barrier Reef Complex has experienced increasing blooms of macroalgae in recent decades. Researchers suggest that this is not the result of overfishing of herbivorous fishes, as many coral reef biologists have previously suggested, but more likely related to external factors, significantly nutrient enrichment.
Because historical nutrient data for seawater and macroalgae were collected in the BBRC in the 1980s, we re-sampled the same sites at South Water Caye (SWC) marine reserve (e.g. Man-O-War Caye), and various sites at Glovers Reef (GR) marine reserve (e.g. Middle Caye) in June 2017 and 2018. Seawater dissolved inorganic nitrogen (DIN) and soluble reactive phosphorus (SRP) concentrations increased from undetectable concentrations in the 1980s to values of 0.5 – 1.0 µM DIN and 0.02-0.05 µM SRP at several reef sites, indicating nutrient enrichment of reef waters. Elevated macroalgal tissue C:N ratios from 22 to 44 occurred at reef sites, suggesting nitrogen limitation; however, lower C:N ratios of 13 to 16 occurred at Middle Caye, GR and Man-O-Way Caye, SWC indicating nitrogen enrichment at these sites. Stable nitrogen isotope values (d13N) were elevated (+3 to + 7 o/oo) at Middle Caye and Man-O-War Caye compared to lower values at reef sites (-0.5 to + 2 o/oo), pointing to significant nitrogen enrichment from humans and seabirds, respectively. These comparative nutrient data support recent suggestions that nutrient enrichment is a significant factor driving macroalgal blooms, declines in hard coral and loss of broader ecosystem services generated by the BBRC.
The Florida Chamber Foundation’s Future of Florida Forum brings together Florida’s business leaders, industry experts and elected officials to discuss the opportunities and challenges impacting Florida’s future between now and 2030. Dr. Lapointe presented a breakout session titled: How Can We Mitigate Florida's Algae Crisis?
Port St. Lucie City Leaders Continue to Look for Solutions For Better Water Quality- ABC25 WPBF News
The City of Port St. Lucie is once again partnering with local scientists to work on another in-depth water quality study.
Mayor Gregory J. Oravec said "We need good science to objectively measure the health of our river, to direct our limited resources to where we can do the greatest good and to measure our progress in a continuous loop. Our ongoing partnership with a leading scientist, like Dr. Lapointe, and a preeminent marine science institution, like FAU Harbor Branch, helps us meet these needs and more".
Read the whole article at the link below.
Dr. Lapointe presented a seminar at the 2018 Reef Environmental Education Festival titled: Stressed Out: Three Decades of Nitrogen Enrichment on Coral Reefs of the Florida Keys and Caribbean Region.
Coral reefs in the Florida Keys and wider Caribbean region have experienced dramatic ecosystem change over the past three decades. Coral bleaching, disease and die-off, combined with expansion of benthic algae and sponges, have transformed reefs in many parts of the Caribbean, especially those adjacent to increasing human activities. Long term water quality monitoring at Looe Key reef in the lower Florida Keys since 1984 showed significant increases in reactive nitrogen and chlorophyll in the 1990s following increased runoff from the Everglades into the Gulf of Mexico and Florida Bay. This data also revealed how periods following increased flows of nitrogen-rich water from the Everglades were followed by three mass bleaching events in 1987, 1997, 2014. Similar replacement of corals with benthic algae has occurred in Discovery Bay, Jamaica, over the past three decades. These case studies illustrate how nitrogen-fueled marine eutrophication is inter-linked to loss of biodiversity on coral reefs along developing coastlines in the wider Caribbean region.
Florida’s rapid population & industrial growth highlights the importance of sewage control. Florida is booming. Unemployment is down, real estate values are up, and the population is growing … fast. There are now 21 million Floridians. Since 2010, the Sunshine State’s population has jumped by 11.6%, more than twice the national average of 5.5%.... Click the article link below to read more.
South Florida’s beaches faced a sargassum assault this summer that some scientists believe is part of the largest spread of the nomadic marine weed on record, and one that could continue through September.
From the Keys through the Treasure Coast, islands of the brown algae floating on berry-like bladders have stained beaches and sailed through inlets thick enough that one Palm Beach County lifeguard saw a black racer snake drift by on one large mat.
In June, sargassum spread through 1,158 square miles of the Caribbean Sea. That’s three times the sargassum coverage during the same time in the record-high year of 2015.
Click the link below to read the full article at the Palm Beach Post.
“We have altered the nitrogen cycle on our planet and it started with the invention of fertilizer,” Lapointe said. “We think this is what is behind the increased abundance of sargassum.”
Our team conducted our second reef survey at Pepper Park Reef. We surveyed the benthic cover at the reef and collected water, macroalgae, and urchin samples. We look forward to analyzing these samples to help us better understand what forces are shaping this reef community.
We are excited to welcome our new summer volunteer, Jody Smith! Jody is an undergraduate student of Environmental Studies at University of California Santa Cruz. She's going to help us in the lab and with fieldwork over the next month. Welcome to the world of algae Jody!
Megan McRoberts of WPTV tagged along for an exciting day of fieldwork surveying coastal reefs for signs of eutrophication with the Lapointe HAB Lab. The story highlighted the importance of this new project. We are looking forward to analyzing the data collected and sharing the results.
Dr. Lapointe spoke to WPTV about the causes of increasing Sargassum beaching in Florida and globally.
Our first sampling trip for a new nearshore reef survey was conducted June 20, 2018 using the Harbor Branch Dusky. The HAB Lab team, Lapointe, Brewton, and Wilking, set out along with our collaborator Alex Tewfik of Wildlife Conservation Society Belize, HBOI photographer Brian Cousin, and WPTV news anchor Megan McRoberts to survey some coastal reefs for reported symptoms of eutrophication. We became aware of the potential problem from divers who were reporting unusual numbers of algae and sea urchins, possible signs of an ecosystem out of balance. We collected, environmental measurements, water samples, and macroalgae samples. Additionally, SCUBA surveys were done of the benthic (algae, wormrock, coral, sponges, etc.) and fish communities. We will try to sample these sites monthly, as visibility and weather conditions allow. The goal will be to understand what is influencing the distribution and abundance of algae and other organisms on these important habitats.
We're excited to welcome our new HAB Lab volunteer, FAU Biology undergraduate student Rachael Stark! Rachael is a senior with a focus in Marine Biology. She will graduate this fall and hopes to attend graduate school next year. We hope that by volunteering in our lab she will learn some valuable skills and get a better idea of the sorts of research that she would like to do in graduate school. She's already been been extremely helpful in the lab by washing bottles and grinding Sargassum samples. Welcome to the world of algae Rachael!
Dr. Lapointe discussed the increased strandings of the brown algae, Sargassum, with the Palm Beach Post. These strandings are an issue for coastal communities in many locations and one of the reasons we study Sargassum. Link to the article below.
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!
Studying water quality and harmful algal blooms throughout Florida and the Caribbean.