Blood-Bellied Jellyfish and Other Strange Sea Creatures Discovered in the Ocean

A recent series of dives off the coast of Southern California led to the discovery of several intriguing gelatinous invertebrates, including jellyfish and siphonophores.

Under the Ocean

During a 10-day mission, the research vessel David Packard traversed the waters of Monterey Bay and the Channel Islands. The main aim of the teams was to study life forms thriving thousands of meters below the surface, in the “midnight zone,” a realm perpetually dark where pressures hundreds of times greater than at the surface prevail.

To observe this cryptic wildlife, teams from the Monterey Bay Aquarium Research Institute (MBARI) relied on a remotely operated submarine equipped with a camera specifically designed to shoot in near-darkness and to capture the faint glow (bioluminescence) emitted by these deep-sea creatures.

Meanwhile, each morning, divers wearing full diving suits were tasked with collecting ctenophores and other species living near the surface, while trawl nets were used to sample representatives of species migrating to deeper waters as night falls.

Among the spectacular creatures observed, visible in the video below, were jellyfish described as “blood-bellied,” “plate jelly,” as well as several species of ctenophores and a siphonophore of the genus Erenna (a close relative of jellyfish) newly identified by science. According to MBARI’s press release, this latter species is distinguished by its sophisticated pendant lures, resembling tentacles.

Essential Adaptations

Devoid of fragile organs, these gelatinous life-forms can endure intense pressures. Notably, certain enzymes have also been identified in many deep-sea jellyfish that help them withstand remarkably low temperatures.

Meanwhile, the mysid shrimp—found in the Gulf of California—relies on a particularly robust exoskeleton. It is also eyeless, a feature that would not serve much purpose in the midnight zone.

Earlier, a giant ghost jellyfish and nearly 30 organisms new to science had already been observed off the Atlantic coast of Argentina.