12 Days of Christmas in the Deep Sea off Tobago

In 2016, Jahson Alemu took us to the Buccoo Reef for creatures to represent ‘12 Days of Christmas.’ To celebrate the 2017 season, marine scientist Diva Amon takes us into the deep ocean! One and half kilometers deep, off the east coast of Trinidad and Tobago, we'll find creatures you can't imagine. Marvel at this Christmas tribute to twelve deep sea inhabitants. There are more wonders lurking in the deep ocean than we know! (All photos courtesy the Ocean Exploration Trust.)

On the first day of Christmas

One swimming sea cucumber (Enypniastes eximia)

Enypniastes eximia is a deep-sea species of sea cucumber (or holothurian) that, unusually, spends a large portion of its life swimming!

On the second day of Christmas

Two chimaeras (Hydrolagus affines)

Hydrolagus chimaeras are also known as spookfish or rabbitfish and are closely related to sharks and rays. They have a venomous spine in front of the dorsal fin. This particular individual also has a large white parasite just behind the pelvic fin on its left side.

On the third day of Christmas

Three serpent stars (Asteroschema sp.) 

Asteroschema serpent stars are closely related to brittle stars and basket stars. They get their name from the sinuous movement of their long thin arms as they coil around the branches of deep-sea corals.

On the fourth day of Christmas 

Four eelpout fish (Pachycara caribbaeum)

Pachycara caribbaeum is an eelpout fish known only from two small deep-sea areas in the Caribbean (the El Pilar methane seeps off Trinidad and Tobago and the Von Damm hydrothermal-vent field in the Cayman Trench). These are known to predate on the numerous shrimp also found at these chemosynthetic locations.

On the fifth day of Christmas,

Five siphonophores (Erenna sp.)

Siphonophores are a group of colonial organisms that includes the well-known shallow-water Portuguese Man o’War. While this siphonophore may appear to be one organism, it is actually comprised of small individual animals known as zooids. They catch prey using sticky stinging cells.

On the sixth day of Christmas

Six octopuses (Graneledone n. sp.)

This is a new species of Graneledone octopus known only at the El Pilar seep sites off Trinidad and Tobago. Although not very much is known about this species yet, a close relative found in the Pacific, Graneledone boreopacifica, has the longest egg brooding or pregnancy period of any animal: a whopping 53 months!

On the seventh day of Christmas

Seven tubeworms (Lamellibrachia sp.)

Lamellibrachia tubeworms are found only at chemosynthetic habitats. They have no mouth or gut and instead rely on internal bacteria that use sulphide-rich chemicals seeping from the seafloor to create food. They can grow to two metres long and it is thought that they can live to be hundreds of years old.

On the eighth day of Christmas

Eight Golden crabs (Chaceon fenneri)

Golden Crabs (Chaceon fenneri) are known from as far south as Brazil and all the way up to the Gulf of Mexico. They are one of the main predators found at the El Pilar seep sites, where they were observed eating Bathymodiolus mussels. They were also observed mating, with the individual pictured laden with eggs.

On the ninth day of Christmas

Nine deep-sea corals (Plumarella sp.)

Contrary to what you may think, the deep-sea harbors the highest diversity of corals in our oceans. Unlike the shallow-water coral reefs like those found at Buccoo Reef, these deep-sea corals do not rely on sunlight and lack the symbiotic photosynthetic algae that produce food. Instead these catch particles passing in the water column. Deep-sea corals are extremely long lived (possibly thousands of years old) and provide complex three-dimensional habitat for many invertebrates and fish.

On the tenth day of Christmas

Ten deep-sea sponges (Haplosclerida n. sp.)

These deep-sea sponges are thought to be a new species and are only known from the El Pilar methane seeps off Trinidad and Tobago. They form a zone peripheral to the mussel beds, which are closest to the areas of hydrocarbon-rich seepage, where they number in the thousands. Next to nothing is known about these sponges but it is suspected given their location that they derive some benefit from the seepage.  

On the eleventh day of Christmas

Eleven methane-seep shrimp (Alvinocaris muricola)

Alvinocaris muricola are one of the most well known deep-sea species. They are found at methane seeps in the Atlantic Ocean, Caribbean Sea and Gulf of Mexico, and have even been found living on a whale skeleton off Brazil! They are often seen within tubeworm bushes and mussel beds and are thought to have a varied diet (bacteria, marine snow and meiofauna).

On the twelfth day of Christmas

Twelve giant mussels (Bathymodiolus childless)

Bathymodiolus mussels are the most conspicuous species at methane seeps. They rely on methane-rich fluid seeping from the seafloor, which is used by internal bacteria to create food, but can also filter feed on particles. These mussels are ecosystem engineers that modify the physical and chemical environment at chemosynthetic habitats, as well as provide hard substrate and shelter for many smaller species.