Weird but wonderful creatures of the deep


What’s deep, dark and foreboding, and yet home to many magnificent creatures? 

With a maximum depth of 7,686 meters, almost 4.7 miles, the Cayman Trough is the deepest area of the Caribbean Sea. It’s pitch black and temperatures are below freezing except for when they’re boiling, but for many creatures, it’s also a very comfortable home. 

Since hydrothermal vents were discovered in the Cayman Trough in 2009, the area has become a hot spot for deep-sea exploration. The research crew aboard the Nautilus, led by renowned explorer Robert Ballard, discoverer of the Titanic and the Bismarck, among others, recently dove the depths of the trough. 

Over the years, various research crews have encountered some very interesting creatures in these dark depths. Some are well-documented, others are new to science, but all are weird and wonderful. 


Rimicaris hybisae 

These eyeless shrimp find the Beebe and Von Damm hydrothermal vent sites positively homey. 

The species was discovered by the crew aboard the Royal Research Ship James Cook in April 2010. The shrimp were named hybisae after the remote-controlled hydraulic benthic interactive sampler, or HyBIS, used to collect the shrimp specimens. 

In place of eyes, these pale shrimp have a light-sensitive organ on their backs. Scientists hypothesize that this organ helps them navigate in the dark. 

These shrimp are not squeamish about invading each others’ space. They cluster around the vent openings by the millions, frequently stepping on and climbing over each other. 

They also might be cannibals. Researchers aboard the Nautilus indicated that a recent investigation of the stomach contents of the shrimp revealed that they might be eating each other, or shrimp of another species. 


Dumbo octopus 

How did it ever get that name? 

Dumbo octopuses use their ear-like fins to help navigate and propel themselves through the water. 

The high-definition cameras aboard the remotely operated vehicle Hercules on the Nautilus captured footage of these deep-dwelling octopuses in the Cayman Trough in August. 

While Dumbo octopuses do not frequent the hydrothermal vents, they do prefer extreme depths. 



The members of this class of echinoderms are commonly referred to as sea cucumbers. 

These leathery creatures feed on debris that collects at the bottom of the ocean, occasionally chatting among themselves by sending out hormone signals. 

In other cultures, sea cucumbers are harvested for human consumption. These holothurians probably thank their lucky stars no one here thinks they look appetizing. 

During their exploration of the Cayman Trough, the crew aboard the Nautilus caught sight of a holothurian with a strange appendage. Was it a parasite? A mutation? A baby holothurian? A sail? The crew really weren’t sure. For all we know, neither was the sea cucumber. 


Dandelion siphonophore 

This is the Portuguese man o’ war’s smaller, less deadly, and far cuter cousin. 

The dandelion siphonophore does indeed look like a flower, but it’s actually a floating colony of individual organisms tethered securely to the sea floor by tentacles. 

The individual organisms that make up siphonophores work so well together that they can appear to be a single creature. So, rather than just being one deadly marine creature, Portuguese man o’ wars are actually well-organized colonies of many deadly marine creatures. 


Squat lobster 

No, this lobster did not lose its tail in a freak fishing accident. It’s just a little bit self-conscious and prefers to keep its tail tucked under its thorax. 

Species of squat lobsters are found around the world, and a few are even harvested for food. There is a great deal of variation across the genus in terms of feeding habits, with some squat lobsters finding detritus delectable, and others refusing to eat anything but sunken pieces of wood. 



The 2011 Woods Hole Oceanographic Institution expedition to explore the hydrothermal vents in the Cayman Trough also discovered the first tubeworms living at vent sites in the Atlantic Ocean. 

The scientists were amazed to see the hydrothermal tubeworms at all, let alone living alongside the newly discovered, blind, cannibalistic Rimicaris hybisae. 

In the Pacific, tubeworms are both abundant and absolutely huge – they can grow as long as 2.4 meters, which some believe is approximately 2.3 meters too long. 



This creature is not actually an eel at all. It’s a bony marine fish that just happens to look very eel-like. 

When the crew of the RRS James Cook returned to the Cayman Trough earlier this year, they dropped a piece of meat in the water and watched as 1.5 meter long cusk-eels appeared out of the darkness to devour it. 

This holothurian has a sail-like fin.


Don’t be fooled by the cute looks, this one is related to the Portuguese man o’ war.


Despite the name, the suck eel is really an eel-like fish.