What Kind of Animals Live in the Benthic Zone

A rich benthic community in the European Arctic. Feather stars, basket stars, this detail sea cucumber (all in the group of echinoderms) and anemones prefer hard bottom equally a substrate. (Photo courtesy of v. Juterzenka, Piepenburg, Schmid). Click image for larger view.

Brittle stars dominate vast areas of the investigated Chill sea floor. The locally high affluence and biomass is adamant by the amount of food available and is sustained by but few species. (Photograph courtesy of v. Juterzenka, Piepenburg, Schmid). Click paradigm for larger view.

These scientists are working on a box core. A box cadre works like a cookie cutter for sediment. Information technology removes a piece of the sea floor with all the animals in and on information technology. Here, the sample has been taken and the metal sides of the core are screwed dorsum together to ready for the next bandage. Click prototype for larger view.

Deep Sea Benthos

Bodil Bluhm
Research Assistant Professor of Marine Biology
School of Fisheries and Ocean Sciences
Academy of Alaska, Fairbanks

Katrin Iken
Assistant Professor of Marine Biology
Academy of Alaska, Fairbanks

Life on the Chill Deep Bounding main Flooring

Animals that alive on the bounding main flooring are called benthos. Nearly of these animals lack a backbone and are called invertebrates. Typical benthic invertebrates include ocean anemones, sponges, corals, bounding main stars, sea urchins, worms, bivalves, venereal, and many more than.

Contempo research indicates that the diversity of species living in the deep-sea may rival the species richness found in tropical coral reefs! At offset, scientists found this puzzling considering nosotros believed that few lifeforms could withstand the harsh, deep regions of the oceans. Even so, now we know that marine benthic organisms are well adapted to their environment and tin live and thrive even in the cold dark waters of the deep ocean.

These animals accommodate to permanently low temperatures such as those establish in the Arctic by having depression metabolic rates. This means that organisms in cold waters live and piece of work at a "lower speed" than organisms in warmer waters. This does not mean, however, that deep-sea organisms do non do as well as organisms from warmer waters. Rather, cold-adaptation means that these animals' enzymes and metabolic processes work best at ambience depression temperatures and at high pressure. Virtually marine invertebrates lack gas-filled body compartments (like lungs in humans) that would collapse at high pressure. Thus, most deep-sea organisms would dice in tropical temperatures or if they were kept in an aquarium. They would need to be kept in special pressurized tanks.

Many deep-sea organisms, including organisms in polar regions, also grow very slowly. In fact, some arctic deep-ocean organisms grow as much in ten years equally some tropical organisms abound in 1 year! This means that polar and deep-sea species live to be much older than tropical species. A polar body of water urchin tin get as erstwhile as your grandmother, simply a tropical one would probable die before its 10th birthday.

Going Hungry at Depth

Food availability strongly determines how well Arctic benthic organisms and communities will develop and abound. Sunlight usually cannot attain below 200 ft, which prevents marine micro- and macro-algae—significant food sources—from growing on the deep ocean flooring. Hence, sea floor animals depend primarily on nutrient particles that rain down from the top of the water column or are transported downwardly forth the continental slopes. A expert portion of this "food rain" is eaten past animals in the h2o cavalcade, leaving the deep-body of water creatures with what petty remains.

Deep-sea areas, therefore, tend to be areas of limited food availability and ofttimes have "bad quality" food. Moreover, ice-covered areas get fifty-fifty less algal product than non-ice-covered areas, resulting in even less "nutrient rain" for the Arctic deep-sea benthos.

And so Much Research, And so Petty Knowledge

The Chill Ocean is characterized past broad, shallow continental shelf areas (boilerplate depth around 50m) which are often nutrient-rich and biologically agile. Some shelf areas of the Due north American Chill are teeming with benthic life such every bit worms, bivalves and crustaceans, which have been studied extensively. Even so, nosotros know piffling about benthic communities at deeper areas of the Arctic Ocean, especially the Canadian Basin with depths around 3000 1000. The long seasonal water ice cover and the great depth return the ocean floor of the deep Arctic Body of water extremely difficult and expensive to access and sample. Only at present do we have adequate ships and equipment to venture into these habitats – but the deep Arctic Ocean remains a claiming.

Our Goals

For this expedition, we hope to detect and identify Arctic abyssal fauna and explore their food web. A remotely operated vehicle (ROV) on board will be our heart at the sea floor. For the commencement fourth dimension, nosotros will encounter what kind of organisms manage to live in this extreme habitat, and how abundant they are. These in situ (onsite) and real-time observations also will tell united states of america something almost their lifestyle and hopefully their feeding habits. By using ROV applied science, we wait to detect species that accept non yet been seen in this surface area or may even be new to science. These collections may change our current view of the seemingly impoverished Chill deep-sea fauna.

Our second objective is to learn about the benthic food web of the deep Arctic benthic community. Fifty-fifty with the use of an ROV, information technology will be a rare and lucky occasion if we are able to detect this. Thus, to augment our observational data, nosotros plan to study naturally occurring isotopes, in particular carbon and nitrogen isotopes, to determine relative trophic positions of species on the broad calibration of communities or ecosystems. During this trek, we hope to trace nutrient sources and follow organic thing flowing through the triangle of the pelagic, the ocean ice and the benthos. The results will tell the states which species feed on relatively fresh cloth (good quality food), which feed on other animals, and which survive on one-time, reworked detritus (bad quality food). The food web analysis of a whole ecosystem will assist the states place key players as well as ecology fundamental factors in the largely unexplored Arctic abyssal ecosystem.

Click here for more data on contempo expeditions studying deep-sea Benthos: Diving to Extremes