It’s a Bioluminescent Red Tide!

April 29, 2020: We are experiencing a red tide, a massive bloom of the dinoflagellate Lingulodinium polyedra, which is a common member of the local plankton community. Sometimes it gets so abundant that it discolors the water reddish/brown, hence the name red tide. And this is big one, stretching from Baja California to Los Angeles. It was first detected at a mooring offshore of the Scripps Pier on March 25, and seen from shore on April 4. So as of this writing it has already persisted for a month.

L. polyedra is bioluminescent, resulting in some spectacular light displays at night as seen in these videos:

For scientific information about the red tide, visit:

Red Tide Bulletin, by the Southern California Coastal Ocean Observing System

Dr. Latz interviews:

ABC 10News San Diego, April 29, 2020

What Is That Terrible Smell?

Glowing Waves Could be Crashing to an End Soon

NBC7 San Diego, May 5, 2020

‘Greater LA’ radio show KCRW, May 7, 2020

San Diego Union Tribune, May 7, 2020

San Diego Union Tribune, May 21, 2020

Update Friday May 1, 2020: The red tide continues. The water near the shore is dark brown in color. There is a pungent smell, indicating the breakdown of organic material. So perhaps the red tide will degrade soon?


Update Monday May 4, 2020: The water is still brown in color, but now the sulfury odor is intense; we smelled it 1 1/2 miles inland. There is also foam, indicating the breakdown of protein and other organic material. There are also reports of fish kills along beaches and in lagoons and harbors. The breakdown of the red tide by microbes results in low oxygen conditions (hypoxia/anoxia) that are deleterious to some animals.

Foam by the Scripps Pier in the morning (top), with more at night (bottom) due to breakdown of the red tide

The end is near! Nighttime bioluminescence on May 4 (top) was much reduced compared to about one week prior on April 24 (bottom), as the health of the red tide organisms degrades. Despite large crowds, there wasn’t much bioluminescence to see.

Update Friday May 22, 2020: The foam has mostly disappeared and the nasty smell is gone. The water is still murky but it appears that the bulk of the red tide has dissipated. Bioluminescence on the night of May 18 was dim but still noticeable. There was considerable foam on the beach on May 19:

Article about Infinity Cube, a Bioluminescence Art Exhibit

In this article, published in the November 2019 issue of Limnology and Oceanography Bulletin, Dr. Latz recounts the making of Infinity Cube, a bioluminescence art exhibit that was displayed at the Birch Aquarium of Scripps Institution of Oceanography during 2017-2018. In collaboration with London-based artist Iyvone Khoo, Infinity Cube consisted of a dark ‘sensorial space’ of video projection and sound within a reflective cube to create an immersive experience, with accompanying graphics to explain the science concepts. #infinitycube

Why is the Iconic Bioluminescent Dinoflagellate Noctiluca not Bioluminescent along the West Coast of the USA?

The dinoflagellate Noctiluca scintillans was described as ‘animalcules’ in the 1750’s using early microscopes and is now known as a major source of bioluminescence in the world’s oceans. But reports going back to the 1960’s describe non-bioluminescent Noctiluca along the west coast  of the USA. In this study, published in the November 2019 issue of Limnology and Oceanography, an international team of scientists including Dr. Latz investigated the mechanisms behind the loss of bioluminescence in this Noctiluca population using molecular, cellular and biochemical analyses of isolates from different geographic regions. Non-bioluminescent Noctiluca lacked luciferin, the substrate molecule for the bioluminescence chemical reaction. The gene for the catalyst luciferase was present but was not expressed as mRNA, most likely because of potentially deleterious mutations. Phylogenetic analysis based on the large subunit rDNA showed no divergence between non-bioluminescent and bioluminescent populations; the only morphological difference was that non-bioluminescent cells were 43% smaller. The ecological significance of the loss of bioluminescence in this population is unknown, as dinoflagellate bioluminescence serves in predator avoidance. The loss of this important functional state provides an opportunity to investigate the evolutionary and ecological mechanisms involved in intraspecific variation in natural populations.

This article is highlighted on the Scripps Oceanography web site.

Remembering Physicist and Educator Dr. Jim Rohr

Jim Rohr had a 30 year career with the Department of Defense at Spawar Systems Center (SSC) Pacific in San Diego, first as a research physicist studying fluid mechanics, underwater acoustics, and marine biology. He obtained a Ph.D. in Engineering Physics at the University of California San Diego (UCSD). He served for several years as a research associate at Scripps Institution of Oceanography, and lectured at UCSD in the Mechanical Engineering and Aerospace Department.

After helping manage SSC Pacific’s research portfolio, he was asked to champion a new outreach program, the purpose of which was to attract more U.S. students to careers in science, technology, engineering and mathematics (STEM). This program grew exponentially and through an army of volunteers soon provided over 200 events a year, involving thousands of students and over a hundred teachers. Retiring from the DoD in 2015, he continued his outreach efforts through the National Marine Mammal Foundation. 

Jim was a personable and energetic scientist and educator, infecting others with his enthusiasm and love of science. We worked together on many projects involving the flow stimulation of bioluminescence. The highlight was studying dolphin hydrodynamics using bioluminescence as a flow marker; Jim arranged for us to work with Navy dolphins at SSC Pacific.

Jim received major awards for community outreach: Spirit of Preuss Award – 2015; Vice Admiral Samuel L. Gravely, Jr., STEM and Diversity Champion of the Year – 2014; UCSD Distinguished Service Award – 2013; DON Meritorious Civilian Service Award – 2012; SSC Pac Center Team Achievement Award – 2011; Navy Key Influencer Award  – 2009; SSC Pacific Technical Director’s Award – 2008.

U.S. Postal Stamps on Bioluminescent Life

The U.S. Postal Service has issued stamps related to bioluminescence. From their web site:

Bioluminescence – the ability of some living things to generate their own light – occurs on many branches of the tree of life. With this sheet of 20 stamps, the U.S. Postal Service showcases 10 examples of Bioluminescent Life.

The stamps feature: deep-ocean octopus, midwater jellyfish, deep-sea comb jelly, bamboo coral, marine worm, crown jellyfish, sea pen (photos by Edith Widder), a second type of marine worm (photo by Steve Haddock), mushroom (photo by Taylor Lockwood), and firefly (photo by Gail Shumway). The selvage features a transparent deep-sea comb jelly (photo by Gregory Dimijian), surrounded by images of the firefly squid (photo by Danté Fenolio). The stamps and selvage were designed by art director Derry Noyes.

What’s In a Name? Lingulodinium polyedra, the dinoflagellate formerly known as L. polyedrum and Gonyaulax polyedra

A 1989 paper by John Dodge rocked the dinoflagellate community. The much loved and studied dinoflagellate Gonyaulax polyedra, known for its spectacular bioluminescent displays and red tides in southern California and elsewhere, was renamed based on new insights into its morphology and to align the name with that of its spiny cyst, then known as Lingulodinium machaerophorum. So the motile form of the dinoflagellate, originally described by Stein in 1883, was changed from Gonyaulax to Lingulodinium because you can’t have two names for the same organism.

Reluctantly we adopted the new name and used it in our publications. However, Lingulodinium polyedra didn’t seem right, based on the word endings, so Lingulodinium polyedrum became commonly used, even though we cited the Dodge 1989 paper, which called it Lingulodinium polyedra. Out of 220 publications since then, 95% used L. polyedrum. Now it’s time to change again. Based on the Latin derivation, polyedrum is incorrect.

According to Brown’s “Composition of Scientific Words” (p. 715):

Gr. hedra, f. seat, chair, base, plane, side; hedrion, n. dim.; hedraios, sitting,
sessile, sedentary, stable, steadfast; hedranon, n. abode, dwelling, seat;
ephedra, f. a sitting by, siege; ephedros, sitting upon; kathedra, f. seat of a
bishop, abode, fundament, rump: hedrocele, tetrahedral, dodecahedron, octahedrite, cathedral, Sanhedrin, chair, chaise, Edrioaster[Hedrioastersaratogensis (a cystoid), Ephedra distachys (a joint-fir), Gonyaulax polyhedra (a flagellate).
So, polyedra, according to this authoritative source, is a noun, which means the name is Lingulodinium polyedra, as nouns are non-declinable when used in apposition.

This is how it is explained in the taxonomic resource AlgaeBase:

Nomenclatural notes
The epithet “polyedra” is a noun in apposition and is non-declinable, so use of the epithet “polyedrum”, supposedly to agree with the gender of the genus name, is incorrect. ICN Art 23.5 [Melbourne Code]: “The specific epithet, when adjectival in form and not used as a noun, agrees grammatically with the generic name; when it is a noun in apposition or a genitive noun, it retains its own gender and termination irrespective of the gender of the generic name. Epithets not conforming to this rule are to be corrected (see Art. 32.2).” – (6 Jan 2018) – M.D. Guiry

The correct name, Lingulodinium polyedra, now appears in AlgaeBase and the World Registry of Marine Species (WoRMS). In a recent publication we referred to it as Lingulodinium polyedra (F. Stein) J. D. Dodge 1989 (formerly Gonyaulax polyedra; by many authors Lingulodinium polyedrum).


Thanks to Michael Guiry for assistance in resolving this issue.

Recovery of Caribbean Bioluminescent Bays after Hurricane Maria

On September 20, Hurricane Maria slammed into the VIrgin Islands as a category 5 hurricane and pounded Puerto Rico as a category 4. With torrential rain and wind gusts up to 200 miles per hour, it caused widespread devastation including loss of electricity and cell service for the entire territory.

The hurricane also impacted four bioluminescent bays. Unlike our local bioluminescent red tides, which are unpredictable in occurrence and appear only every couple of years, the bioluminescent bays of the Caribbean exhibit bright bioluminescence throughout the year and are extremely popular for ecotourism and contribute greatly to the local economy. These bays are extremely rare mangrove ecosystems, with a total area less than 5 sq km in the Caribbean. The four impacted bioluminescent bays include three in Puerto Rico and one in St. Croix, US Virgin Islands.
Three of the four bioluminescent bays went dark after Maria, due to multiple factors including freshwater runoff and high winds. The good news is that the bioluminescence of Mosquito Bay in Vieques, Laguna Grande in Fajardo, and the Salt River Bay bioluminescent bay in St. Croix have recovered. Phosphorescent Bay in La Parguera was largely spared.
El Yunque, the only tropical rainforest within the territorial U.S., is closed indefinitely because of major slides that blocked the access road.
Everyone has been working hard to clear debris to allow ecotourism activities to be re-established. Nighttime tours should resume within a few weeks to most of the bioluminescent bays. According to one tour operator:
“I have never seen the amount of Federal works from all over the United States, forest rangers, FEMA, US Corp of Engineers, US Fish and Wildlife and the army all engaged with the island and the rebuilding of the rainforest!  We have outside Electric companies from NC, TX and others working to reestablish the light and communications!”

“The Artistry of Dinoflagellate Bioluminescence”

In a new article, Dr. Latz explores his artist collaborations in expressing the aesthetic beauty of nature in a creative way that avoids the technical details and jargon that tend to limit the effectiveness of science communication. The objective of the artists’ works is to engage the viewer and perhaps provide the opportunity to educate the curious about science. The article describes the motivation behind the collaborations and includes representative artwork.

You can download the article here: Latz2017_artistry of dinoflagellate BL

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