Indicator assessment
This indicator shows the percentage of fish stocks in seas
around the UK that are both harvested sustainably and are at full
reproductive capacity. This is based on a group of 20 indicator
stocks for which there are reliable estimates of fishing mortality
and spawning biomass and which together represent the fish stocks
of major importance to the UK fishing industry. Since 2001, between
15 and 30% of fish stocks have been at full reproductive capacity
and harvested sustainably, up from between 10% or less in the
1990s, and 5% in 2000. The assessment of change for the indicator
is therefore positive in both the long and short term.
Despite this improvement over time, the majority of UK fish
stocks have either been below full reproductive capacity or have
been harvested unsustainably each year since 2001.
Description of trends
The proportion of the assessed fish stocks
harvested sustainably and at full reproductive capacity remained at
15% or below in the period 1990 to 2000. This is equivalent to
three or fewer of the 20 stocks assessed consistently over the
period. Since 2001, the proportion of stocks at full reproductive
capacity and harvested sustainably has been consistently
higher at between 15 and 30%.
Relevance
Fish are an integral component of marine
biodiversity. They are an important element of the food chain for
seabirds, seals and cetaceans and are a source of food and
employment for people. Sustainable fisheries will help to
ensure our marine ecosystems remain diverse and resilient and
provide a long term and viable fishing industry.
The long and short term assessments both
indicate an increase in the percentage of fish stocks which are at
full reproductive capacity and being harvested sustainably, with a
marked improvement since 2000. However, substantial further
improvements in stock status would be needed to ensure that all UK
fish stocks are fished sustainably. In 2004, the Royal
Commission on Environmental Pollution advised significant and
urgent action to avoid further collapse of fisheries or harm to the
marine environment6.
In 2008, the UK Government submitted the
Marine and Coastal Access Bill to Parliament. Amongst other
initiatives, this Bill sets out proposals for improved fisheries
management and a network of protected areas. It is one of the key
response to the Royal Commission report.
6.Royal Commission on Environmental Pollution.
2004. Turning the Tide: Addressing the Impact of Fisheries
on the Marine Environment.London, the
Stationary Office
Background
This UK indicator takes into account 9 species
in 20 UK stocks for which there are estimates of fishing mortality
and spawning stock biomass throughout the period 1990 to 2007. Each
stock refers to a population of a species occurring in a defined
sea area, and a particular species may occur in multiple stocks in
waters around the UK. Table 9 shows the fish species included in
this measure (note the species and stocks included are the same as
in the previous assessment).
The indicator only uses stocks for which the
International Council for Exploration of the Sea (ICES) is able to
present an analytical assessment with data from 1990 to the present
time. The only exception is Rockall haddock for which there were no
data for 1990 (there are therefore only 19 stocks in 1990).
ICES classifies a stock’s status by comparing
the quantity of mature fish (the spawning stock biomass) and the
rate at which the stock is exploited, in relation to agreed
reference levels. The stock trends and reference levels are
obtained from fishery and survey data from each zone. Spawning
stock biomass is categorised as either at full reproductive
capacity, being at risk of suffering reduced reproductive capacity
or suffering reduced reproductive capacity. Rate of fishing
mortality is categorised as harvested sustainably, at risk of being
harvested unsustainably or harvested unsustainably. The UK
indicator shows the proportion of the 20 stocks that are at full
reproductive capacity and harvested sustainably in each year.
Each year ICES updates the assessment of each
stock with another year of fishery and survey data, or may revise
an assessment to include new time-series of data or adopt an
improved method of analysis. This can result in significant changes
to the trends in spawning stock biomass and rate of exploitation,
causing changes to the historical values in the UK indicator
series. On the basis of new evidence, ICES may also provide advice
on stocks for which the assessments were previously considered
unreliable, or stop providing advice for stocks for which the
assessments are no longer considered reliable. For example, in 2007
ICES stopped providing advice for two western anglerfish stocks,
and these were removed from the UK indicator reducing the number of
stocks from 22 to 20.
Table 9. Fish species included in this indicator
|
Clupea harengus (Herring)
|
Micromesistius poutassou (Blue
whiting)
|
|
Gadus morhua (Cod)
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Pleuronectes platessa (Plaice)
|
|
Melanogrammus aeglefinus
(Haddock)
|
Pollachius virens (Saithe)
|
|
Solea solea (Sole)
|
Scomber scombrus (Mackerel)
|
|
Merluccius merluccius (Northern
hake)
|
|
Source: International Council for Exploration
of the Sea (ICES) Advisory Committee on Fisheries Management
reports; Centre for Environment, Fisheries and Aquaculture Science
(CEFAS).