Evidence of sewage-driven eutrophication and harmful algal blooms in Florida's Indian River Lagoon

The Indian River Lagoon (IRL), located on the east coast of Florida, is a complex estuarine ecosystem that is negatively affected by recurring harmful algal blooms (HABs) from distinct taxonomic/functional groups. Enhanced monitoring was established to facilitate rapid quantification of three recurrent bloom taxa, Aureoumbra lagunensis, Pyrodinium bahamense, and Pseudo-nitzschia spp., and included corroborating techniques to improve the identification of small-celled nanoplankton (<10 μm in diameter). Identification and enumeration of these target taxa were conducted during 2015–2020 using a combination of light microscopy and species-specific approaches, specifically immunofluorescence flow cytometry as well as a newly developed qPCR assay for A. lagunensis presented here for the first time. An annual bloom index (ABI) was established for each taxon based on occurrence and abundance data. Blooms of A. lagunensis (>2 × 108 cells L–1) were observed in all 6 years sampled and across multiple seasons. In contrast, abundance of P. bahamense, largely driven by the annual temperature cycle that moderates life cycle transitions and growth, displayed a strong seasonal pattern with blooms (105–107 cells L–1) generally developing in early summer and subsiding in autumn. However, P. bahamense bloom development was delayed and abundance was significantly lower in years and locations with sustained A. lagunensis blooms. Pseudo-nitzschia spp. were broadly distributed with sporadic bloom concentrations (reaching 107 cells L–1), but with minimal concentrations of the toxin domoic acid detected (<0.02 μg L–1). In summer 2020, multiple monitoring tools characterized a novel nano-cyanobacterium bloom (reaching 109 cells L–1) that coincided with a decline in A. lagunensis and persisted into autumn. Statistical and time-series analyses of this spatiotemporally intensive dataset highlight prominent patterns in variability for some taxa, but also identify challenges of characterizing mechanisms underlying more episodic yet persistent events. Nevertheless, the intersect of temperature and salinity as environmental proxies proved to be informative in delineating niche partitioning, not only in the case of taxa with long-standing data sets but also for seemingly unprecedented blooms of novel nanoplanktonic taxa.

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Volunteer Algae Monitoring Program (VAMP) in the Indian River Lagoon

Marine Technology Society Journal ◽

10.4031/mtsj.52.4.7 ◽

2018 ◽

Vol 52 (4) ◽

pp. 88-93

Author(s):

Susan Hamburger ◽

Kenneth T. Gioeli ◽

David Berthold ◽

H. Dail Laughinghouse

Keyword(s):

Water Quality ◽

Harmful Algal Blooms ◽

Algal Blooms ◽

Monitoring Program ◽

Indian River Lagoon ◽

Fort Lauderdale ◽

Quality Testing ◽

Indian River ◽

Research And Education ◽

The University

AbstractThe University of Florida's Institute of Food and Agricultural Sciences (UF/IFAS) Florida Master Naturalist Program (FMNP) is an adult environmental education program with more than 450 trained program graduates in St. Lucie County, Florida. It is a collaborative effort of the UF/IFAS Extension St. Lucie County, St. Lucie County Environmental Resources Department, and partner agencies. Four UF/IFAS Florida Master Naturalist volunteers were recruited and received training and supplies to conduct water quality testing and algae collection in the Indian River Lagoon as part of the Volunteer Algae Monitoring Program (VAMP). The UF/IFAS research and extension faculty developed VAMP in response to the 2016 harmful algal blooms (HABs) in the Indian River Lagoon that resulted in dramatic impacts on businesses, residents, and visitors in Martin, St. Lucie, and Indian River counties. These HAB episodes demonstrate the importance of having informed citizen scientists with an understanding of the problems and threats. The VAMP citizen scientists conducted a water quality awareness survey with the general public after proactively scouting for HABs by collecting samples and conducting water quality testing at three waypoints in the Indian River Lagoon during May to November 2017 (excluding October) and February 2018. They utilized UF/IFAS Water Watch chemistry tests and processed and shipped water samples to the Laughinghouse Lab at the UF/IFAS Fort Lauderdale Research and Education Center, which conducted algae counts and genetic testing to determine the presence of harmful algae expressing microcystin-producing genes. Test results indicated fluctuating and inconsistent levels of saxitoxin but no indications of microcystins across the three sites and over time.

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Mesozooplankton Community Dynamics and Grazing Potential Across Algal Bloom Cycles in a Subtropical Estuary

Frontiers in Marine Science ◽

10.3389/fmars.2021.734270 ◽

2021 ◽

Vol 8 ◽

Author(s):

L. Holly Sweat ◽

Hunter Alexander ◽

Edward J. Phlips ◽

Kevin B. Johnson

Keyword(s):

Harmful Algal Blooms ◽

Algal Blooms ◽

Community Dynamics ◽

Algal Bloom ◽

Indian River Lagoon ◽

Environmental Data ◽

Brown Tide ◽

Mesozooplankton Community ◽

Indian River ◽

Subtropical Estuary

Mesozooplankton, as abundant grazers of microalgae in coastal systems, have the potential to prevent or mitigate harmful algal blooms (HABs) and their effects. The Indian River Lagoon (IRL) is a subtropical estuary in eastern Florida (United States) where repeated blooms, dominated by the toxic dinoflagellate Pyrodinium bahamense, the brown tide species Aureoumbra lagunensis, pico/nano planktonic cyanobacteria and other nano-eukaryotes, have highlighted the need to better understand fluctuations in the grazing potential of mesozooplankton populations across bloom cycles. Mesozooplankton and abiotic environmental data were collected at five sites in the northern IRL system at 6-week intervals from November 2013 through June 2016. A total of 107 taxa from 14 phyla were detected. Communities varied across sites, dates and between bloom and non-bloom periods, with densities up to 338 individuals L–1. Eight taxa comprising 85–94% of the total population at each site were identified as primary potential grazers, including barnacle nauplii, cladocerans, adult copepods, gastropod veligers, larvaceans, and polychaete metatrochophores. Although abundant, the estimated grazing potential of the primary taxa, calculated from their measured densities and previously published grazing rates, suggest that mesozooplankton lack the capacity to suppress phytoplankton once they reach bloom levels. These findings illustrate the utility of monitoring data and underscore the importance of systematically evaluating algal bloom controls with a consideration for the dynamic conditions of each unique ecosystem.

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The interactive roles of nutrient loading and zooplankton grazing in facilitating the expansion of harmful algal blooms caused by the pelagophyte, Aureoumbra lagunensis, to the Indian River Lagoon, FL, USA

Harmful Algae ◽

10.1016/j.hal.2015.09.005 ◽

2015 ◽

Vol 49 ◽

pp. 162-173 ◽

Cited By ~ 20

Author(s):

Yoonja Kang ◽

Florian Koch ◽

Christopher J. Gobler

Keyword(s):

Harmful Algal Blooms ◽

Algal Blooms ◽

Nutrient Loading ◽

Indian River Lagoon ◽

Zooplankton Grazing ◽

Indian River ◽

Aureoumbra Lagunensis

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High Densities of a Prochlorophyte (Unresolved Species) Inhibit Grazing by the Herbivorous Copepod Parvocalanus crassirostris

Frontiers in Marine Science ◽

10.3389/fmars.2021.664153 ◽

2021 ◽

Vol 8 ◽

Author(s):

Xiao Ma ◽

Charles A. Jacoby ◽

Kevin B. Johnson

Keyword(s):

Harmful Algal Blooms ◽

Algal Blooms ◽

Algal Species ◽

Indian River Lagoon ◽

Isochrysis Galbana ◽

Total Density ◽

Top Down ◽

Parvocalanus Crassirostris ◽

High Concentrations ◽

Cell Densities

Harmful algal blooms (HABs) are increasing in frequency and severity, underscoring the importance of understanding potential top-down controls of blooms. In the Indian River Lagoon (IRL), a shallow subtropical estuary, one harmful bloom was co-dominated by an unresolved prochlorophyte in the Family Prochlorothricaceae, which reached densities of > 106 cells ml–1 engendering the term “Superbloom.” Experiments were conducted to evaluate grazing rates and the potential for top-down control by an abundant herbivorous copepod, Parvocalanus crassirostris, on the prochlorophyte. Those grazing rates were lower than the rates on a palatable alternative algal food, Isochrysis galbana, when both algal species were presented in monocultures with identical densities. Grazing on the prochlorophyte decreased or ceased at densities over 4.8 × 105 cells ml–1. When the prochlorophyte and the palatable alternative each comprised half of the total density, both species were consumed, but grazing on I. galbana was reduced compared to the grazing rates in a monoculture of this species, especially at higher cell densities. Copepod mortality was observed in treatments with high concentrations of the prochlorophyte, and these treatments contained mucilage. Experiments simulating viscosities produced by prochlorophyte mucilage yielded results consistent with the original grazing experiments (i.e., copepods showed lower grazing rates and higher mortality rates in higher viscosity treatments). Results reveal potential limitations of top-down controls by this grazer on prochlorophyte blooms and HABs that produce mucilage.

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255. Public Health Response to Harmful Algal Blooms

10.3320/1.2765781 ◽

2001 ◽

Author(s):

P. Webb

Keyword(s):

Public Health ◽

Harmful Algal Blooms ◽

Algal Blooms ◽

Public Health Response ◽

Health Response

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National coastal management challenges and needs

Shore & Beach ◽

10.34237/1008843 ◽

2020 ◽

pp. 34-43

Author(s):

Nicole Elko ◽

Tiffany Roberts Briggs

Keyword(s):

Coastal Management ◽

Harmful Algal Blooms ◽

Algal Blooms ◽

Local Community ◽

Extreme Event ◽

Technical Information ◽

Interdisciplinary Approach ◽

Beach Erosion ◽

The U.S

In partnership with the U.S. Geological Survey Coastal and Marine Hazards and Resources Program (USGS CMHRP) and the U.S. Coastal Research Program (USCRP), the American Shore and Beach Preservation Association (ASBPA) has identified coastal stakeholders’ top coastal management challenges. Informed by two annual surveys, a multiple-choice online poll was conducted in 2019 to evaluate stakeholders’ most pressing problems and needs, including those they felt most ill-equipped to deal with in their day-to-day duties and which tools they most need to address these challenges. The survey also explored where users find technical information and what is missing. From these results, USGS CMHRP, USCRP, ASBPA, and other partners aim to identify research needs that will inform appropriate investments in useful science, tools, and resources to address today’s most pressing coastal challenges. The 15-question survey yielded 134 complete responses with an 80% completion rate from coastal stakeholders such as local community representatives and their industry consultants, state and federal agency representatives, and academics. Respondents from the East, Gulf, West, and Great Lakes coasts, as well as Alaska and Hawaii, were represented. Overall, the prioritized coastal management challenges identified by the survey were: Deteriorating ecosystems leading to reduced (environmental, recreational, economic, storm buffer) functionality, Increasing storminess due to climate change (i.e. more frequent and intense impacts), Coastal flooding, both Sea level rise and associated flooding (e.g. nuisance flooding, king tides), and Combined effects of rainfall and surge on urban flooding (i.e. episodic, short-term), Chronic beach erosion (i.e. high/increasing long-term erosion rates), and Coastal water quality, including harmful algal blooms (e.g. red tide, sargassum). A careful, systematic, and interdisciplinary approach should direct efforts to identify specific research needed to tackle these challenges. A notable shift in priorities from erosion to water-related challenges was recorded from respondents with organizations initially formed for beachfront management. In addition, affiliation-specific and regional responses varied, such as Floridians concern more with harmful algal blooms than any other human and ecosystem health related challenge. The most common need for additional coastal management tools and strategies related to adaptive coastal management to maintain community resilience and continuous storm barriers (dunes, structures), as the top long-term and extreme event needs, respectively. In response to questions about missing information that agencies can provide, respondents frequently mentioned up-to-date data on coastal systems and solutions to challenges as more important than additional tools.

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