Water samples gathered and tested in the year-long study by researchers at FAU’s Harbor Branch provide multiple lines of evidence that human wastewater nitrogen from septic systems was a major contributor to the high nitrogen concentrations in the estuary and downstream coastal reefs.

“It has long been thought that the algal blooms found in Lake Okeechobee, which are caused by pollution such as runoffs from farms, were solely responsible for driving the blooms and their toxins in the St. Lucie Estuary,” said Brian E. Lapointe, Ph.D., lead author of the study and a research professor at FAU Harbor Branch, who recently presented these findings at the ninth U.S. National Harmful Algal Bloom Conference. “We wanted to investigate the role of on-site septic systems, which have previously been overlooked.”

From the study samples, Lapointe and his collaborators clearly identified that wastewater contamination is a significant driver of water quality decline and ecological dysfunction in the St. Lucie Estuary and downstream nearshore reefs. Evidence from the samples they gathered and tested showed that human wastewater nitrogen from septic systems was a major contributor to the high nitrogen concentrations in the estuary and downstream coastal reefs, the latter representing the northernmost extent of coral growth in South Florida.

Read the full press release here.

(Photo credit: Bob Hogensen, Martin County, Florida)

NOAA’s new report,  State of Deep-Sea Coral and Sponge Ecosystems of the United States, explains advances in deep-sea coral research over the past decade and how this new information is shaping deep-sea conservation. Each of the report’s 13 peer-reviewed chapters was written by leading U.S. researchers, including a chapter each by FAU Harbor Branch's own John Reed and Shirley Pomponi, Ph.D.

Six regional chapters summarize new research—much of it led by NOAA—and explain how results have led to improvements in deep-sea management. It also shares an understanding of coral and sponge taxonomy, species distributions, fisheries habitats, and the effects of human activities.

These chapters serve as a ten-year update to the first State of Deep Coral Ecosystems of the United States report, published in 2007, and provide the first look at U.S. deep-sea sponge ecosystems. 

For report highlights click here.

To read the full report click here. 

FAU Harbor Branch’s Population Biology and Behavioral Ecology Program is using DNA ‘fingerprinting’ to monitor the population size of beluga whales in Alaska. Collaborating with Alaska Natives and with scientists from the Alaska Department of Fish and Game and the National Marine Fisheries Service, the FAU team of Greg O’Corry-Crowe, Tatiana Ferrer and Brooke Potgieter co-authored a paper that was recently published in  Marine Mammal Science.

The small population of beluga whales in Bristol Bay, Alaska has received increasing attention in recent years over concerns about the potential impacts of climate change, oil and gas development and mining within the headwaters of Bristol Bay rivers, home to the largest commercial sockeye salmon fishery in the world. Efficient, reliable estimates of abundance and trend are critical to effective management of this population. However, almost every aspect of studying marine mammals, especially in the seasonally ice covered waters of the North, is challenging. Estimating abundance and monitoring trends in beluga whales has relied on aerial surveys which are both costly and prone to many sources of bias.

The team, therefore, took a radically different approach: Genetic Mark-Recapture. This approach adapts the principals of mark-recapture abundance estimation by using DNA profiling of individual whales to detect genetic ‘recaptures’ from subsequent sampling efforts. By systematically collecting tiny tissue biopsies from free-swimming whales over several years and conducting the DNA ‘fingerprinting at the Harbor Branch lab, the team was able to estimate the size of the population from the frequency of ‘recaptured’ (i.e. re-sampled) individuals in their sample set. The study has established the method as an effective alternative approach to population monitoring of beluga whales worldwide and of other cetacean species.

View the paper here.

The paper, entitled "An Approach for Automatic Classification of Grouper Vocalizations with Passive Acoustic Monitoring," was recently accepted in the Journal of the Acoustic Society of America (JASA) and was authored by FAU Harbor Branch Associate Research Professor, Laurent Chérubin, Ph.D., and his student Ali Ibrahim from the Department Computer & Electrical Engineering and Computer Science, College of Engineering at FAU. Co-authors of the paper are Hanqi Zhuang (FAU), Michelle Schärer (University of Puerto-Rico), F. Dalgleish (FAU Harbor Branch), Nurgun Erdol (FAU), B. Ouyang (FAU Harbor Branch), and A. Dalgleish (FAU Harbor Branch).

The paper describes a method to automate the detection and classification of courtship associated sounds produced by four species of groupers of the western tropical Atlantic Ocean. This method is based on machine-learning and voice recognition algorithms. The method is currently being implemented on Harbor Branch's SV3 wave glider and for two years has been used to discover fish spawning aggregations in the Virgin Islands and Puerto-Rico. 

The team also built a small app called FADAR (Fish Acoustic Detection Algorithm Research), which has been shared with various research entities who are monitoring spawning aggregations in the Caribbean (Cayman Islands, Department of Environment) and in the U.S. (University of the Virgin Islands, University of Puerto-Rico, Scripps Institution of Oceanography). Chérubin and Ibrahim continually work on the development of FADAR, adding new species and retraining the algorithm with new data, and adding new methods that are species specific, all in one package.  

This work has been possible thanks to grants from the Harbor Branch Oceanographic Institute Foundation, National Oceanic and Atmospheric Administration (NOAA) Saltonstall-Kennedy, and NOAA's Office of Ocean Exploration and Research through the Cooperative Institute for Ocean Exploration, Research & Technology.

[Image] Nassau grouper CAS spectrogram: distribution of the sound energy in frequency-time space