Demersal fish

General Information

North Sea

Baltic Sea

Clyde Marine Region

Adriatic Sea

Eastern Mediterranean Sea

Demersal fish

Layer Info
Category	Ecology
Sub-category	Fish

Description

Demersal fish is a type of fish that is primarily inhabits the lower depths of a body of water, particularly the ocean floor. The term "demersal fish" does not refer to a specific species, but rather it describes a group or category of fish based on their shared habitat preference.

These fish are adapted to life near or on the seabed, and are commonly found in coastal areas, continental shelves, and deep-sea environments. These types of fish share features that make them well-suited for this habitat, such as flattened bodies, strong pectoral fins, and specialized feeding structures. This group of species can be subdivided into 'large' and 'small' demersal fish, and includes various types of flatfish, cod, flounder, skates, and many more. Demersal fish play a crucial role in marine ecosystems as they interact with other species in the benthic (bottom-dwelling) environment.

Small demersal fish

Example species: Grey gurnard

Habitat: Demersal
Main role: Predator
Trophic level: 4,5

Diet: Juveniles feed on a variety of crustaceans. The diet of older specimens consists mainly of juvenile fish.

Threats: Grey gurnards are of lesser commercial importance and are mostly caught as bycatch for other flatfish.

Large demersal fish

Example species: Thornback ray

Habitat: Demersal
Main role: Predator
Trophic level: 3,8

Diet: This ray feeds on fish and invertebrates.

Threats: Of commercial interest and near threatened according to IUCN red list. The thornback ray is often caught as bycatch by trawl and gillnets.

Information

As mentioned on the general page for Demersal fish, this group of species can be subdivided into 'large' and 'small'. For each group one species will be discussed in more detail. In the North Sea Edition the following species are defined as small Demersal fish: Eelpout (Zoarces viviparus), Shorthorn Sculpin (Myoxocephalus scorpius), Vahls’s Eelpout (Lycenchelys vaillanti), Longspined Bullhead (Taurulus bubalis), Hooknose (Himantolophus groenlandicus), Common Seasnail (Liparis liparis), Greater Weaver (Trachinus draco), Lesser Weaver (Trachinus radiatus), Snake Blenny (Lumpenus lampretaeformis), Striped Red Mullet (Mullus surmuletus), Solenette (Buglossidium luteum), Thickback Sole (Microchirus variegatus), Mediterranean Scaldfish (Arnoglossus imperialis), Argentine (Argentina sphyraena), Dragonet (Callionymus lyra), Piper Gurnard (Trigla lyra), Red Gurnard (Aspitrigla cuculus), Grey Gurnard (Eutrigla gurnardus).

The following species are included in the large Demersal fish group: Rabbit Fish (Chimaera monstrosa), John Dory (Zeus faber), Sea Trout (Salmo trutta), Norway Red Fish (Sebastes norvegicus), Bluemouth (Helicolenus dactylopterus), Roundnose Grenadier (Coryphaenoides rupestris), Starry Ray (Raja radiata), Spotted Ray (Raja montagui), Common Skate (Dipturus batis), Cuckoo Ray (Leucoraja naevus), Thornback Ray (Raja clavata).

Types

• Very Low Density
• Low Density
• Medium Density
• High Density
• Very High Density

Metadata

Data Source

Demersal fish is a month-by-month, computer generated data layer following calculations made by the ecosystem simulation (EwE). For more information on how Ecopath-with-Ecosim (EwE) works, please visit our Wiki page or visit the official EwE website at https://ecopath.org.

For detailed information on how the simulation works for the North Sea Edition, we recommend further exploring our research publication called "Combining ecosystem modeling with serious gaming in support of transboundary maritime spatial planning".

Not applicable. This layer is currently not integrated into the MSP Challenge Baltic Sea Edition.

Not applicable. This layer is currently not integrated into the MSP Challenge Clyde Marine Region Edition.

Not applicable. This layer is currently not integrated into the MSP Challenge Adriatic Sea Edition.

Not applicable. This layer is currently not integrated into the MSP Challenge Eastern Mediterranean Sea Edition.