The drifters

The drifters A homage to the beauty and diversity of the smallest animals in the sea

Below the sea surface,

below the feet of bathing people,

below the whirle of ships propellers,

lies the world of the oceans' smallest animals.

The world of zooplankton.

A world of alien beauty.

A colony of jellies (siphonophores) emerges from the deep, gently floating with the ocean currents. A gelatinous thread holds the colony's inhabitants together.

Serving the colony is a major focus of each individual. While some are the colony's hunters, others are the colony's stomach, digesting what the hunters serve. Yet, others work as flotation.

Species name: Nanomia cara

Also the hula skirt siphonophore is a colony, shaped like a series of bells on top of each other. Also they are contributing loyally with different tasks to the entire colony's well being. The orange colored tentacles at the base of the colony are used for hunting and may cause painful stings.

Species name: Physophora hydrostatica

And here is what they eat. A small crustacean (copepod), no larger than a few millimeter in length. Also he is a drifter, taken along with the movement of the sea. Yet when attacked, this little fellow can jump at record-breaking speed. It is not an easy catch!

Species name: Gaidius tenuispinus

Out in the Barents Sea at the rim of the deep Arctic Ocean:

On deck of the Norwegian research icebreaker 'Kronprins Haakon', marine biologists Padmini Dalpadado and Anette Wold investigate the catch of the day. Also they are hunting for small crustaceans in the sea.

For their hunt, the two scientists have lowered a gigantic cylindrical net deep into the sea.

As the net is pulled slowly upwards through the water, crustanceans and other inhabitants of the sea are trapped.

In the net haul, a large crustacean (amphipod) of intens red-organge colour was caught. This chuncky fellow is good feed for fish down in the darkest depths of the sea.

Species name: Cyclocaris guilelmi

Also this is a small crustacean, but with a clam-shell like cover over its body. It swims by sticking out the antennae and legs through the shell.

As Cyclocaris guilelmi, this little fellow is a scavanger, living of whatever it finds of dead and left material.

Species: unidentified ostracod

For the researchers, the true work begins upon retrieval of the net.

The entire catch has to be sorted by hand. One by one, crustacean by crustacean, jelly by jelly.

Padmini is especially interested in the krill, which is an important food source for fish, whales and birds in the North Atlantic and southern Barents Sea.

Under the stereo microscope, Padimini checks the collected krill for species composition.

The total abundance of the krill in the catch will give Padmini and her colleagues an indication of the size and condition of the krill's population.

Nordic krill is with its 4-5 cm no large fellow, but is a good swimmer. During daytime, krill hides in the darkness of the ocean depth. As night falls, it migrates to the sea's upper layer where it finds its food - microscopically small algae floating in the sea. These algae are so tiny that krill has its own filtering apparatus to get a hold of them - small, hair-like legs are used to filter algae from the water.

Species name: Meganyctiphanes norvegica

Also this is a plant-eating crustacean. Copepods are likely to be the most abundant invertebrates on our planet. As krill, many copepods efficiently convert algae into fat and protein, providing a nutrious meal to many - from other zooplankton, to fish, whales and birds. There would be little for us to fish in the sea without these few millimeter large animals.

Species name: Calanus glacialis

Researchers like Padmini and Anette spend hundreds of hours of their life studying organisms like krill, copepods and the other drifters of the ocean.

This is not because of their beauty alone, but because understanding the species and their role in the sea ultimately provides us humans with deeper understanding of our world, and how it is about to change.

Changes are seen on all corners.

Also down here.

Also among these alien looking creatures.

Anette, together with many other scientists, has witnessed some of these changes.

For many years, she has especially followed three little fellows looking quite alike.

Calanus hyperboreus, Calanus glacialis, and Calanus finmarchicus.

Calanus hyperboreus is with his up to 7 mm length the giant among the three.

Calanus glacialis is with his up to 4 mm intemediate in size.

In contrast, Calanus finmarchicus is the little brother, not reaching more than 3 mm.

All three are the Cheeseburgers of the sea. Cram-full of fat, they are a feast for all who can catch them. For all predators, the menu reads the following:

Quater Pounder Deluxe 9.2 oz = Calanus hyperboreus

Big Mac 7.5 oz = Calanus glacialis

Hamburger 3.5 oz = Calanus finmarchicus

Which Burger would you choose if you were really hungry and had a baby to feed?

Little auks (species name: Alle alle) (c) AWeith, CC BY-SA 4.0, via Wikimedia Commons

Birds like Little auks choose Big Mac 7.5 oz.

But this dish is no longer so easy to find in the vicinity of the bird's colonies.

Climatic changes have led to a rise in seawater temperatures in parts of the Arctic where the Little auk lives.

Anette and other researchers have observed how warmer water favours Calanus finmarchicus over Calanus hyperboreus.

For the Little auk that means a diet shift from Big Mac 7.5 oz to Hamburger 3.5 oz.

The result is a decrease in Little auks in many regions of the Arctic.

(c) Lena Seuthe

Also for us humans it matters which creature is abundant when and where in the sea.

It impacts for example where, when and what we can fish, which shellfish we can farm, and if the sea is clean enough for us to bathe in.

(c) Lena Seuthe

Next time you swim or eat fish, you can think of the drifters of the ocean. Tiny animals wandering with the ocean currents.

Think of their beauty.

Think of that they all have a role to play in the huge food web of the ocean and our world.

When it comes to Physophora hydrostatica, is not found in the Arctic.

Not yet.

Fredrik Broms (northernlightsphotography.no) worked as marine biologist who then also took up professional photography. Using his biological background, Fredrik has taken pictures of many marine animals found in along the Norwegian and Svalbard coast, as well as in the Barents Sea. All pictures of zooplankton used here, were taken by Fredrik.

Christian Morel (christianmorel.net) joined a research cruise to the Arctic in August 2019 to illustrate the research conducted within the research project 'The Nansen Legacy'. All pictures of scientists in the field used here, were taken by Christian.

The Nansen Legacy (nansenlegacy.org) is a novel research project that will provide integrated scientific knowledge on the rapidly changing marine climate and ecosystem of the Barents Sea and adjacent Arctic Ocean. The Nansen Legacy unites about 280 researchers, students, and technicians from ten Norwegian research institutions. The research team includes interdisciplinary arctic marine expertise within physical, chemical, and biological oceanography, as well as geologists, modelers and underwater robotic engineers. Jointly we investigate the past, present and future climate and ecosystem of the northern Barents Sea. In total, the project will spend over 350 days at sea between 2018 and 2022, using the new Norwegian research icebreaker ‘Kronprins Haakon’ as main research platform. The ship-based sampling is complemented by the use of underwater robotics, year-round moored observing platforms and satellite-based observations. Complementary model tools are used to integrate field-based observations, and to investigate the dynamics of the physical and biological components of the northern Barents Sea climate and ecosystem at present and in the future.

Created By

Lena Seuthe

Appreciate