Fish and Shellfish Stocks 2012

HADDOCK STOCKS — ROCKALL

Rockall haddock ( Melanogrammus aeglefinus), by weight, is the most abundant demersal species landed from this area. It is exploited by two main fleets: Russian vessels deploying small mesh nets (40-70 mm), and the European fleet using demersal trawl gear with a cod-end mesh of 120 mm and above.

2012 position : UK share 2,660 tonnes
Last Year : 3,022 tonnes
Landed into Scotland in 2010 : 2,931 tonnes
Value for 2010 : £3.8 million

Biology

Haddock are distributed throughout the Rockall Bank area and can be found at depths down to 600m, although they are mainly concentrated in the 150 to 300m depth range. Juvenile haddock are mainly found in the shallower waters of the central Bank, at depths less than 180m. There is strong evidence to suggest that Rockall haddock form a separate stock from those found on the continental shelf of the British Isles. The northward flowing surface current between Rockall and the Hebrides may act as a barrier preventing eggs and larvae reaching Rockall from the east or southeast. This hypothesis is supported by tagging studies showing that no haddock tagged from other stocks have been recovered from Rockall.

The haddock found on the Bank have much slower growth rates and a smaller size at age than haddock from other areas. Sampling information by MSS observers has also shown that over 80% of Rockall haddock are sexually mature at age 2. The first spawning of a newly matured female produces around 80,000 eggs, with this number increasing as the fish gets older. Spawning takes place between March and May, with the eggs being released in batches. The eggs and larvae are distributed in the upper water column, and drift north-easterly. Once the juveniles reach 5-10 cm in length they gradually migrate and settle on the sea bottom.

Rockall haddock eat a variety of foods, preferring benthic organisms, with fish and detritus becoming an increasing part of the diet during periods of large stock size. The fish feed preferentially during the summer and autumn, putting on weight until the spawning period when the intensity of feeding significantly decreases.

ICES ADVICE ON MANAGEMENT

Information Source: ICES advice 2011 ( http://www.ices.dk/committe/acom/comwork/report/2011/2011/had-rock.pdf). Quoted text in italics.

MSY and precautionary approach reference points

State of stock and advice

• Fishing mortality has decreased over time and for 2010 was estimated at 0.15: this means that nearly 14%, by number, of all fish between 2 and 5 years of age were caught
• The spawning stock biomass has increased in recent years and has been above B _pa since 2003. For 2011 it was estimated to be around 13,000 tonnes.
• Fishing mortality and biomass are below and above, respectively, the precautionary approach limits and the level which is consistent with achieving maximum sustainable yield ( F ₂₀₁₀ < F _MSY ).
• The advice is in accordance with the MSY approach which recommends human consumption landings in 2012 of 3,300 tonnes from Division VIb.

The EU and the Russian Federation have developed a management plan for this stock that is currently being evaluated by ICES. For the time being, the Russian fleet is not limited by any quota regulation, although in recent years very few Russian vessels have fished at Rockall.

To increase the chance that the spawning stock remains above B _pa in 2013 ICES has recommended that the precautionary approach rate of fishing mortality (0.36) not be used, but the MSY framework rate (0.30) be utilised.

For 2012 the spawning stock biomass is estimated to be at B _pa but the incoming recruitment over the last five years has been low, leading to a high probability that the spawning stock biomass will decrease to levels below B _pa in the near future.

Management outcomes for 2012

At the December 2011 meeting in Brussels, the Council of Ministers decided that the international Total Allowable Catch for Rockall (VIb, XII and XIV) haddock should be 3,300 tonnes. The UK quota for 2012 is set at 2,660 tonnes.

This quota decision was in line with scientific advice advising a reduction in catch. The final quota was adjusted by Hague preference.