Sargasso Sea shift reveals dramatic decline in some historic seaweed populations https://phys.org/news/2025-12-sargasso-sea-shift-reveals-decline.html

#SargassoSea #sea #seaweed #environment

Sargasso Sea shift reveals dramatic decline in some historic seaweed populations

A study led by researchers at the University of South Florida's College of Marine Science has found that certain populations of the seaweed sargassum have experienced a significant decline over the past decade, even as increased abundance of sargassum in the tropical Atlantic has caused large mats of the seaweed to inundate beaches across the Caribbean and Gulf regions.

Phys.org

Sargassum — a specific type of seaweed that washes up on beaches in Galveston and other locales along the Texas coast — has long been native to the Atlantic Ocean, but has only recently begun to grow exponentially.

https://www.houstonpublicmedia.org/articles/news/local/galveston/2025/05/02/520477/scientists-probe-potential-reasons-for-semi-annual-seaweed-surge-on-texas-coast/

#EnergyEnvironment #Galveston #HealthScience #Local #News #Weather #GalvestonBeaches #SargassoSea #Sargassum #SeaweedOnTexasCoasts #TexasAMUniversity #TheGreatAtlanticSargassumBelt

Seaweed surges on Texas coast prompt scientists to study reasons behind recent exponential growth

The natural currents of the Atlantic Ocean cause great masses of sargassum to periodically drift from Africa to South America and eventually to North America, where it is deposited on the beaches along the Texas and Florida coastlines.

Houston Public Media

I remember this story from last year...

#Pathogen’ Storm: #VibrioBacteria, #Sargassum and #Plastic Marine Debris

By gisele galoustian | 5/18/2023

"A new study uncovers how the interplay between Sargassum spp., plastic marine debris and Vibrio bacteria creates the perfect 'pathogen' storm that has implications for both marine life and public health. Vibrio bacteria are found in waters around the world and are the dominant cause of death in humans from the marine environment. For example, Vibrio vulnificus, one of more than 100 species of Vibrio, sometimes referred to as flesh-eating bacteria, can cause life-threatening foodborne illnesses from #seafood consumption as well as disease and death from open #wound infections.

"Since 2011, Sargassum, free-living populations of brown macroalga, have been rapidly expanding in the #SargassoSea and other parts of the open ocean such as the Great Atlantic Sargassum Belt, including frequent and unprecedented seaweed accumulation events on beaches. Plastic marine debris, first found in surface waters of the Sargasso Sea, has become a worldwide concern, and is known to persist decades longer than natural substrates in the marine environment.

"Currently, little is known about the ecological relationship of vibrios with Sargassum. Moreover, genomic and metagenomic evidence has been lacking as to whether vibrios colonizing plastic marine debris and Sargassum could potentially infect humans. As summer kicks into high gear and efforts are underway to find innovative solutions to repurpose Sargassum, could these substrates pose a triple threat to public health?

"Researchers from Florida Atlantic University and collaborators fully sequenced the genomes of 16 Vibrio cultivars isolated from eel larvae, plastic marine debris, Sargassum, and seawater samples collected from the Caribbean and Sargasso seas of the North Atlantic Ocean. What they discovered is Vibrio pathogens have the unique ability to 'stick' to microplastics and that these microbes might just be adapting to plastic.

“'Plastic is a new element that’s been introduced into marine environments and has only been around for about 50 years,' said Tracy Mincer, Ph.D., corresponding lead author and an assistant professor of biology at FAU’s Harbor Branch Oceanographic Institute and Harriet L. Wilkes Honors College. 'Our lab work showed that these Vibrio are extremely aggressive and can seek out and stick to plastic within minutes. We also found that there are attachment factors that microbes use to stick to plastics, and it is the same kind of mechanism that pathogens use.'

"The study, published in the journal Water Research , illustrates that open ocean vibrios represent an up to now undescribed group of microbes, some representing potential new species, possessing a blend of pathogenic and low nutrient acquisition genes, reflecting their pelagic habitat and the substrates and hosts they colonize. Utilizing metagenome-assembled genome (MAG), this study represents the first Vibrio spp. genome assembled from plastic debris.

"The study highlighted vertebrate pathogen genes closely related to cholera and non-cholera bacterial strains. Phenotype testing of cultivars confirmed rapid biofilm formation, hemolytic and lipophospholytic activities, consistent with pathogenic potential.

"Researchers also discovered that zonula occludens toxin or 'zot' genes, first described in Vibrio cholerae, which is a secreted toxin that increases intestinal permeability, were some of the most highly retained and selected genes in the vibrios they found. These vibrios appear to be getting in through the gut, getting stuck in the intestines and infecting that way.

"'Another interesting thing we discovered is a set of genes called ‘zot’ genes, which causes leaky gut syndrome,' said Mincer. 'For instance, if a fish eats a piece of plastic and gets infected by this Vibrio, which then results in a #LeakyGut and diarrhea, it’s going to release waste nutrients such #nitrogen and #phosphate that could stimulate Sargassum growth and other surrounding organisms.'

"Findings show some Vibrio spp. in this environment have an ‘omnivorous’ lifestyle targeting both plant and animal hosts in combination with an ability to persist in oligotrophic conditions. With increased human-Sargassum-plastic marine debris interactions, associated microbial flora of these substrates could harbor potent opportunistic pathogens. Importantly, some cultivation-based data show beached Sargassum appear to harbor high amounts of Vibrio bacteria.

"'I don’t think at this point, anyone has really considered these microbes and their capability to cause infections,' said Mincer. 'We really want to make the public aware of these associated risks. In particular, caution should be exercised regarding the harvest and processing of Sargassum biomass until the risks are explored more thoroughly.'"

https://www.fau.edu/newsdesk/articles/perfect-pathogen-storm.php

#WaterIsLife #Microplastics #PlasticPollution #Anticonsumerism #Degrowth
#PlasticAlternatives #CleanUpYourMess #BigCorporations #Consumerism #Advertising

‘Pathogen’ Storm: Vibrio Bacteria, Sargassum and Plastic Marine Debris

As summer kicks off and efforts are underway to find solutions to repurpose Sargassum, could the interplay between this seaweed, Vibrio bacteria and plastic marine debris pose a triple threat to public health?

@RustyRing @nurglerider @Deiru

Eeyupp...

Even the #SargassoSea may sound chill due to being mostly devoid of currents and waves and winds but that doesn't change the fact that it's a major pathway for #Hurricanes and those will wreck havoc on ships...

#Neuston: Of Terms in Biology https://schaechter.asmblog.org/schaechter/2023/09/da-capo-of-terms-in-biology-neuston.html @STCmicrobeblog

"The presence of a gelatinous surface microlayer film had been proposed in 1983, based partly on observations of the slick associated with blooms in the #SargassoSea of the filamentous #cyanobacteria #Trichodesmium... What about the ocean surface film from the #microbial neustonian point of view? It might appear to be an immense #biofilm stretching from horizon to horizon... Estimates of its thickness range from 1 to 50 µm"

[da capo] Of Terms in Biology: Neuston

<p>by Merry  <br /> When I stumbled across the term bacterioneuston, I discovered a whole new world where the air meets the sea. I found that marine neuston had long been used to refer to the diverse flora and fauna inhabiting the topmost 5 cm of the oceans — a distinctly different assemblage than found in the waters below.

Small Things Considered

If you are interested in life on the #ocean surface, check out this Essay from
@RebeccaRHelm

The mysterious ecosystem at the ocean’s surface

http://plos.io/3uao06E

and the paper

Floating life (#neuston) & trash cluster in the #GreatPacificGarbagePatch. High neuston abundance was only known in the #SargassoSea, but @this_fionachong @RebeccaRHelm &co reveal high densities of floating life in the plastic-rich GPGP #PLOSBiology

https://plos.io/3LXY3CC

#neuston #MarineLife

The mysterious ecosystem at the ocean’s surface

The mysterious ’neuston’ ecosystem at the ocean’s surface includes keystone organisms like the golden seaweed Sargassum that makes up the Sargasso Sea, floating barnacles, snails, nudibranchs, and cnidarians; this Essay explores threats to its wellbeing and the importance of further research.

Floating life (#neuston) & trash cluster in the #GreatPacificGarbagePatch. High neuston abundance was only known in the #SargassoSea, but @this_fionachong @RebeccaRHelm &co reveal high densities of floating life in the plastic-rich GPGP #PLOSBiology https://plos.io/3LXY3CC
High concentrations of floating neustonic life in the plastic-rich North Pacific Garbage Patch

Floating life (neuston) is a core component of the ocean surface food web, but the Sargasso Sea in the North Atlantic is the only known region of high neustonic abundance. This study reveals high densities of floating life in the plastic-rich Great Pacific Garbage Patch, suggesting that this area could be an important marine habitat.

Floating life (#neuston) & trash cluster in the #GreatPacificGarbagePatch. High neuston abundance was only known in the #SargassoSea, but @this_fionachong @RebeccaRHelm &co reveal high densities of floating life in the plastic-rich GPGP #PLOSBiology https://plos.io/3LXY3CC
High concentrations of floating neustonic life in the plastic-rich North Pacific Garbage Patch

Floating life (neuston) is a core component of the ocean surface food web, but the Sargasso Sea in the North Atlantic is the only known region of high neustonic abundance. This study reveals high densities of floating life in the plastic-rich Great Pacific Garbage Patch, suggesting that this area could be an important marine habitat.

Floating life (#neuston) & trash cluster in the #GreatPacificGarbagePatch. High neuston abundance was only known in the #SargassoSea, but @this_fionachong @RebeccaRHelm &co reveal high densities of floating life in the plastic-rich GPGP #PLOSBiology https://plos.io/3LXY3CC
High concentrations of floating neustonic life in the plastic-rich North Pacific Garbage Patch

Floating life (neuston) is a core component of the ocean surface food web, but the Sargasso Sea in the North Atlantic is the only known region of high neustonic abundance. This study reveals high densities of floating life in the plastic-rich Great Pacific Garbage Patch, suggesting that this area could be an important marine habitat.

Did you know that no one has seen #eels reproduce?? Not even in captivity? Did you know that even though eels die right after breeding season, no one has seen an eel (dead or alive) at their supposed breeding ground?? Did you know all eels are born and return to breed and die in the #SargassoSea (IN THE BERMUDA TRIANGLE)!!? Why are they so mysterious! So spooky! 🐍🐟

Currently reading #TheBookOfEels by Patrick Svensson.