Marine Science - Blog Posts

thejoyofscience

6 years ago

“What’s that on the beach?!"

Monterey Bay beachcombers and divers were treated to a huge bloom of salps this weekend! Salps are gelatinous filter-feeders that drift with and feed in the plankton. Wind and waves sometimes blow these open-ocean emissaries onshore by the thousands, a feast for fishes, invertebrates—and for the eyes of curious naturalists!

There were several species of salps in this weekend’s bloom, including these in the genus Salpa. Salps do not sting—in fact, they’re more closely related to fishes and people than they are to other "jellies”! The brown/orange orb is the salp’s gut. Pumping muscle bands push water from one end of the animal to the other through an internal plankton-pasta strainer.

Salps have an incredibly successful reproductive strategy, allowing them to explode in numbers when conditions are right. Ready? Here we go: Salps can be found as solos, or as a chain of dozens of individuals attached together. Same species, two different body morphs. The solos produce the chain asexually, and the individuals in the chain are all clones.

OK, still with us? The next part is a doozy: A young chain is female, and each female clone produces another solo salp from an egg that is fertilized by older male chains. The older male chains are female chains that changed sex as they aged—this is called sequential hermaphroditism. This whole process allows salps to produce new generations at an incredible rate, to take advantage of fleeting oceanic conditions. Phew, we did it!

Salps are thought to have an outsized effect on the flow of nutrients in the ocean’s food web. Because their fecal pellets sink, salp poop delivers vital nutrition from the ocean surface to the deep seafloor, and helps take carbon from the atmosphere to the deep, which helps regulate the planet’s climate. Spent salps from these huge blooms become food for countless organisms throughout the water column. Certain deep sea communities may even depend on these ephemeral feasts to survive in the desert of the abyssal plain, according to research by our colleagues at the Monterey Bay Aquarium Research Institute (MBARI).

This weekend’s salp bloom is a jiggly reminder of the vast community of gelatinous drifters—the gelata—that drift in the open ocean, connecting the surface to the deep and adjusting the Earth’s energy flow, unseen by most until a chance encounter on the shore.

Photo: Charles Schrammel Gif: Alison Smith

Giants lurk in the ocean’s mysterious midwaters.

While surveying the Gumdrop Seamount off the central California coast in 1998, MBARI staff spotted an unusual—and exceptionally large—jelly. This crimson creature was a full meter across. Unlike jellies that dwell near the ocean’s surface, this one didn’t have tentacles. Instead, a cluster of finger-like oral arms dangled beneath its bulky bell.

A closer look confirmed this was a new species—and one that had actually eluded our scientists five years earlier. Detailed video observations captured by our robotic submersibles helped MBARI researcher George Matsumoto and his colleagues in California and Japan formally describe this unusual jelly. They named it Tiburonia granrojo in honor of MBARI’s now-retired remotely operated vehicle (ROV) Tiburon, which was instrumental in documenting this delicate drifter in its natural environment.

Scientists have since spotted this jelly across the Pacific Ocean, from Baja California to Hawaii to Japan. That something so big remained undiscovered for so long shows how little we’ve explored the deep sea—and what more must be out there waiting to be found.

FIRST-EVER FOOTAGE OF INDONESIAN COELACANTH IN NORTH MALUKU REVEALS NEW INSIGHTS INTO RARE SPECIES

The coelacanth, often dubbed a "living fossil," is one of the most iconic and mysterious marine vertebrates. Long thought extinct until its rediscovery in 1938, only two species are known today—Latimeria chalumnae in the western Indian Ocean, and L. menadoensis in Indonesia. The latter, the Sulawesi coelacanth, lives in deep, difficult-to-access reef habitats and has rarely been observed alive. For the first time, divers using advanced technical diving equipment have filmed a live Indonesian coelacanth in situ, at a depth of over 150 metres in North Maluku, a region where the species had not previously been recorded.

Left profile of the coelacanth, with its unique pattern of white dots. Photo by Alexis Chappuis.

- Localities from whence the Sulawesi Coelacanth, Latimeria menadoensis, has been reported in black stars. White star shows the North Maluku Province, where the first in situ sighting by technical divers was made.

This sighting is more than just a milestone in exploration—it provides critical data on the ecology and distribution of an animal that is evolutionarily unique and highly vulnerable. With few individuals ever seen in the wild, each observation adds valuable insight into how these ancient fish live and where they might still be found. It also underscores the urgency of protecting deep reef habitats that are increasingly at risk from human activities. Understanding and safeguarding the ecosystems that support the coelacanth is essential if we hope to ensure its survival into the future.

Main photo: Deep diver about a meter behind the coelacanth discovered at a depth of -144 m in North Maluku, Indonesia. Photo by Alexis Chappuis.

Reference (Open Access): Chappuis et al. 2025 First record of a living coelacanth from North Maluku, Indonesia. Sci Rep