Fisheries Infosite

Environmental Issue

 Deepwater (scampi) trawl - Bycatch

Issue
Large volumes of bycatch are taken in all scampi fisheries. 
Risk
Scampi fishing in New Zealand has been shown to decrease seabed biodiversity in fished areas.
Extent of the issue
Much of the bycatch consists of other commercial species such as ling, hoki and sea perch which are managed under the Quota Management System (QMS). With the exception of a few speices such as spiny dogfish, all species managed under the QMS must be retained. Non-QMS species can be discarded at sea provided the quantities caught are accurately reported. In the New Zealand fisheries, total discards were estimated to be in the range of 3200 to 6800 tonnes per year, compared to an annual scampi catch of between 800-1000 tonnes.

Scampi trawl fisheries also have interactions with some protected species. Seabirds and marine mammals have occasionally been caught in scampi trawls, although this is not a common occurence. Bottom trawling for scampi has been observed to reduce benthic biodiversity in heavily fished areas. To date, benthic impacts have been addressed by closing areas to bottom trawling. Large areas of seafloor have been closed to trawling and dredging under the Benthic Protection Area (BPA) initiative, which in total protects more than 30% of New Zealand's EEZ to bottom fishing methods. Approximately 11% of habitat in the depth range of scampi is protected.

Scampi fisheries occurr along much of New Zealand's east coast in water depths around 200-500m. Bycatch in the New Zealand scampi fishery is about average for a crustacean trawl fishery and includes many species of fish already managed under the QMS.
Trends
Trends are unknown. However, scampi catch rates and bycatch seems to fluctuate quite a lot between years.
Current management
The government is currently getting more information on this issue, by promoting better identification and recording of bycatch in the scampi fishery.
Future management
Future management actions will be informed by the current research. 
Documents / links
Reducing bycatch in scampi trawls 2006.