Sebastes viviparus (Krøyer 1845), Small redfish (Sebastidae)

Author: Ronald Fricke, Germany

1. Description of the habitat/autecology of the species

The small redfish Sebastes viviparus inhabits rocky bottoms, from close to shore to deeper waters, at depths of 10-760 m, mostly in the upper 150 m. The deep sea species lives in large shoals and moves closer to the shore in summer. It feeds on various small crustaceans and young fishes. It is viviparous. It gets sexually mature at an age of 10-15 years. Maximum total length 35 cm, maximum weight 1 kg, maximum individual age 40 years (Froese & Pauly, 2005).

2. Distribution (past and present)

Restricted to Kattegat area where it is occasionally found. Outside the HELCOM area, it is distributed from the English Channel north to northern Norway and East Greenland.

3. Importance (sub-regional, Baltic-wide, global)

Following the definition in HELCOM (2007), small redfish is considered to be of local importance in the western HELCOM area.

4. Status of threat/decline

This species is threatened, and its populations have been declining throughout its range in the HELCOM area and also in the European Atlantic waters. Management measures have failed to improve the situation of populations of the species. In the HELCOM area, this species is classified as endangered (EN) according to IUCN criteria, and is classified as a HELCOM high priority species (HELCOM, 2007). The species is listed as near threatened (NT) by Sweden.

5. Threat/decline factors

Threatened by fisheries as target species, and also by other demersal fisheries (mainly as by-catch in shrimp trawls). The species is not rare, but sensitive to human activities, and a keystone species.

6. Options for improvement

This species would benefit from a restricted demersal fisheries management in its distribution area. In order to bring down the by-catches in the shrimp fishery, it is recommended to that sorting grids attached to the trawl should be mandatory. The species may benefit from marine protected areas with restrictions on demersal fisheries. As the main threats occur outside the HELCOM area in the neighbouring OSPAR area, conservation schemes could be considered there as well.

7. References 

Froese R. & Pauly D. (eds) 2005. FishBase. Available in: www.fishbase.org, version (11/2005).

HELCOM 2007. HELCOM Red list of threatened and declining species of lampreys and fish of the Baltic Sea. Baltic Sea Environmental Proceedings, No. 109, 40 pp.  Available in: http://www.helcom.fi/stc/files/Publications/Proceedings/bsep109.pdf