Biscuit Skate

(Raja straeleni)

Biscuit, skate

WWF-SA recognition of the ET Project as an FCP for the inshore trawl fishery is temporarily on hold until there is agreement between rights holders in the sector on the continued implementation of the ET Project.

1. What is it?

Biscuit skates (Raja straeleni) are long-lived, slow growing, cartilaginous fish. They tend to mature quite late and have a low fecundity making them susceptible to over fishing. There is no directed fishery for skates as they are commonly caught as bycatch. No stock assessment has been done on them but there are some indications that they are overfished due to declines in catch abundances.

2. How was it caught or farmed?

Inshore demersal trawl

Biscuit skates are caught as bycatch in the inshore trawl fishery, which targets sole and hake (hake catches are MSC certified). The fishery gear consists of trawl nets that are dragged along the seabed at different depths up to the 110 m isobath or to 20 nautical miles from the coast, whichever is the greater distance. Demersal trawling is known to damage the seabed; the extent and impact of this damage remains unknown. Trawling is not a selective fishing method and a number of other species are often caught in the nets (fish, sharks and rays). Substantial effort has been made to reduce seabird deaths through the use of tori lines and substantial effort is underway to better manage the principal bycatch stocks through a co-management pilot programme.

Offshore demersal trawl

Biscuit skates are caught as bycatch within the within the offshore demersal trawl industry for hake (MSC certified) using trawl nets that are dragged along the sea bed at depths typically ranging from 110 m to 800 m (known as “demersal trawl nets”). This type of trawling is known to damage the seabed; the extent and impact of damage remains unknown. Trawling is not a very selective fishing method and a number of other species are often caught in the nets (fish, sharks and rays). Sea bird interactions with trawl cables near the surface are also a major concern. A success story in the fishery has been the implementation of effective seabird mitigation strategies developed in connection with the MSC-certification process. These strategies have resulted in a dramatic reduction in sea bird-fishery interactions through the introduction of tori lines (lines covered in coloured streamers making attachment lines more visible to birds) and improved disposal of offal (discard that attracts seabirds).

3. Where is it from?

Inshore demersal trawl

Biscuit skates are caught as bycatch on the continental shelf edge and upper slope along the West Coast and on the South Coast primarily around the Agulhas Bank. Management is considered to be largely effective. Management is mainly directed at the target species hake (MSC certified) and sole in the form of Total Allowable Catch (TAC) and permit limitations. A fishery conservation project (FCP) was developed to test a co-management approach for 10 non-target species in the sector. Other concerns include the lack of information on impacts to sensitive shark, skates and ray populations as well as impacts to the seabed. Efforts are underway to improve the scientific observer coverage at sea for this sector to better understand ecosystem impacts.

Offshore demersal trawl

Biscuit skates are caught as bycatch on the continental shelf edge and upper slope along the West Coast from the Namibian border southwards and on the South Coast primarily around the Agulhas Bank. Management is mainly focused on (hake) in the form of Total Allowable Catch (TAC) and permit limitations. There are some ecosystem-based management measures in place such as precautionary catch limits on monkfish and kingklip, tori lines to reduce sea bird interactions, and limited fishing areas (i.e. fishing within a “footprint” to limit seabed disturbance). The ongoing Fishery Conservation Project (FCP) aims to improve the management of the main bycatch species as well as address any potential impacts on sharks, rays and other sensitive marine species and habitats.