Medidas de Gestao das Pescarias Marinhas e Aquicultura 2019 The State of World Fisheries and Aquaculture 2018 | Page 55

THE STATE OF WORLD FISHERIES AND AQUACULTURE 2018
» they constituted the large majorit y, and
THE STATUS OF FISHERY
RESOURCES
Bangladesh, Myanmar and Sri Lanka, where
they represented up to 50 percent of the total.
In the selected countries in Europe, Latin
America and the Caribbean and Oceania, the
great majorit y of the vessels were motorized.
Marine fisheries
Sustainability of fishing levels
Information on vessels is essential for effective
performance-based fisheries governance. It is
therefore a serious concern that data on vessels
are often most lacking for small-scale fisheries,
which are t ypically a key source of livelihoods
and nutrition for coastal communities. n
Based on FAO’s monitoring of assessed stocks
(see FAO, 2011a for methodolog y), the fraction of
fish stocks that are within biologically
sustainable levels (see Box 2) has exhibited a
decreasing trend from 90.0 percent in 1974 to 66.9
percent in 2015 (Fig ure 14). In contrast, the
BOX 2
ABOUT STOCK STATUS CLASSIFICATION
Definitions
In The State of World Fisheries and Aquaculture, fish
stocks are classified into two categories:
„ „ Fished within biologically sustainable levels:
stocks with abundance at or above the level
associated with maximum sustainable yield
(MSY)
„ „ Fished at biologically unsustainable levels: stocks
less abundant than the level needed to produce
MSY
In previous editions the category “maximally
sustainably fished” was labelled “fully fished”. That
term was often misinterpreted and has been modified
for greater conceptual clarity.
How to use the classification results
It is recommended that fishery managers:
„ „ DO manage fisheries at maximally sustainably
fished levels when food production is a priority
and the maximum sustainable yield can be
harvested without compromising the reproductive
capacity of the stock.
„ „ DO keep particular fish stocks underfished if a
precautionary approach is warranted to protect
the status of the ecosystem in question, consistent
with ecosystem-based approaches.
„ „ DO reduce fishing intensity to rebuild fish stocks
when they are assessed as overfished.
„ „ DO NOT overfish a stock, as it will not only
reduce long-term yield but also have negative
impact on biodiversity and ecosystem functioning
and services.
„ „ DO NOT group the categories “maximally
sustainably fished” and “overfished”. The former
is generally the target of fishery management,
while the latter is a situation to be avoided or
overcome through fishery regulations.
The percentage of stocks fished within biologically
sustainable levels is the indicator used to measure
progress towards the Sustainable Development Goals
(SDGs) target for marine fisheries (target 14.4), and can
therefore be used for SDG monitoring and reporting (see
“Fisheries and the Sustainable Development Goals:
meeting the 2030 Agenda” in Part 2).
Stocks are also characterized in three more
traditional categories, to give more information about
the production potential of a fish stock in relation to its
current status:
„ „ Overfished: having abundance lower than the
level that can produce MSY
„ „ Maximally sustainably fished: having abundance
at or close to the level of MSY
„ „ Underfished: abundance above the level
corresponding to MSY
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