Report of the 2005 ICES/NASCO Symposium on Interactions ...

NINA SPECIAL REPORT 34
1. Introduction
1.1 Background
Paradoxically, at a time when <strong>the</strong>re is serious concern
about <strong>the</strong> status <strong>of</strong> wild Atlantic salmon stocks, <strong>the</strong>
abundance <strong>of</strong> salmon in <strong>the</strong> North Atlantic Ocean has
probably never been higher as a result <strong>of</strong> <strong>the</strong> rapid growth
<strong>of</strong> salmon farming.
Since <strong>the</strong> early 1980s, farming <strong>of</strong> Atlantic salmon has
become a major industry, with production in <strong>2005</strong> <strong>of</strong>
approximately 785,000 tonnes in <strong>the</strong> North Atlantic, a
reduction compared to 2004 (831,000 tonnes) but a 5%
increase on <strong>the</strong> previous five-year mean production. Most
<strong>of</strong> this production occurred in Norway (72%) and
Scotland (17%). The provisional worldwide production in
<strong>2005</strong> was approximately 1.3 million tonnes with Chile
producing approximately 405,000 tonnes. The worldwide
production <strong>of</strong> farmed Atlantic salmon is approximately
600 times <strong>the</strong> reported catch <strong>of</strong> salmon in <strong>the</strong> North
Atlantic (<strong>ICES</strong>, 2006a). Progress is being made in
managing <strong>the</strong> interactions between wild and farmed
salmon, and collaboration between wild and farmed
salmon interests is improving (Anon, 2006). However, <strong>the</strong>
wild stocks are in a weakened state and vulnerable to a
wide range <strong>of</strong> anthropogenic impacts. There are,
<strong>the</strong>refore, concerns about <strong>the</strong> disease, parasite, genetic,
and ecological impacts <strong>of</strong> salmon farming on wild salmon
stocks (Hansen et al., 1991; Hutchinson, 1997;Youngson et
al., 1998; Hutchinson, 2006). A regime is required that
allows <strong>the</strong> industry to prosper but, at <strong>the</strong> same time,
safeguards <strong>the</strong> wild stocks so as to maintain <strong>the</strong> social and
economic benefits from both wild and farmed salmon.
This has not been, and will not be, easy. Currently, <strong>the</strong>
Atlantic salmon is to <strong>the</strong> fore but, as aquaculture develops
and diversifies into o<strong>the</strong>r species, <strong>the</strong> wild stocks <strong>of</strong> <strong>the</strong>se
and o<strong>the</strong>r species may be affected, and <strong>the</strong> nature <strong>of</strong>
interactions may be similar.
Interactions between cultured and wild salmon are not
restricted to those arising from salmon farming. In
response to <strong>the</strong> decline in <strong>the</strong> abundance <strong>of</strong> wild salmon
stocks, cultured fish are stocked for mitigation, restoration,
and rehabilitation purposes. Fur<strong>the</strong>rmore, although
‘commercial’ ranching <strong>of</strong> salmon is no longer undertaken
in <strong>the</strong> North Atlantic, <strong>the</strong>re is interest in ranching to
support recreational fisheries in some rivers. A regime is
required under which <strong>the</strong> risks as well as <strong>the</strong> benefits are
carefully considered before deliberately releasing any
cultured fish into <strong>the</strong> wild.
2
In response to concerns about interactions between
salmon aquaculture and <strong>the</strong> wild salmon stocks, a series <strong>of</strong>
international meetings aimed at reviewing scientific
understanding <strong>of</strong> interactions and providing guidance on
appropriate management responses has been convened.
The first major international symposium on this subject,
sponsored by <strong>the</strong> Norwegian Directorate for Nature
Management and <strong>NASCO</strong>, was held in Loen, Norway, in
1990 (Hansen et al., 1991). <strong>NASCO</strong> was sufficiently
concerned by <strong>the</strong> gravity <strong>of</strong> <strong>the</strong> threats and <strong>the</strong>ir
potentially irreversible nature that, in 1991, it adopted
guidelines designed to minimise impacts <strong>of</strong> aquaculture on
<strong>the</strong> wild stocks. These guidelines were replaced three
years later by <strong>the</strong> Oslo Resolution, which in turn was
replaced in 2003 by <strong>the</strong> Williamsburg Resolution
(<strong>NASCO</strong>, 2006a). This Resolution was developed to
ensure that <strong>the</strong> measures taken by <strong>NASCO</strong> Parties and
<strong>the</strong>ir relevant jurisdictions to minimise <strong>the</strong> impacts <strong>of</strong>
aquaculture, introductions and transfers, and transgenics
were consistent with <strong>the</strong> Precautionary Approach. The
development <strong>of</strong> <strong>the</strong> Williamsburg Resolution drew on
information presented at a second major international
symposium, convened by <strong>ICES</strong> and <strong>NASCO</strong>, held in Bath,
England, in 1997, which reviewed <strong>the</strong> scientific and
management aspects <strong>of</strong> interactions between salmon
culture and <strong>the</strong> wild salmon stocks (Hutchinson, 1997;
Youngson et al., 1998).
Since <strong>the</strong> first symposium in 1990, production <strong>of</strong> farmed
salmon in <strong>the</strong> North Atlantic has more than trebled.
Aquaculture is certainly not <strong>the</strong> only threat to <strong>the</strong> wild
salmon stocks, and <strong>NASCO</strong> is addressing a wide range <strong>of</strong>
o<strong>the</strong>r issues relating to salmon conservation and
management (e.g. <strong>the</strong> management <strong>of</strong> fisheries and habitat
protection and restoration) and has recently established
an International Atlantic Salmon Research Board to
investigate <strong>the</strong> factors influencing <strong>the</strong> mortality <strong>of</strong> salmon
at sea and <strong>the</strong> opportunities to counteract <strong>the</strong>m. The
Board has recently endorsed an ambitious international
programme <strong>of</strong> research, <strong>the</strong> SALSEA programme,
containing a comprehensive mixture <strong>of</strong> freshwater,
estuarine, coastal and <strong>of</strong>fshore elements, ensuring a
thorough overview <strong>of</strong> factors which may affect <strong>the</strong>
mortality <strong>of</strong> Atlantic salmon at sea.
<strong>NASCO</strong> and <strong>ICES</strong> believe that <strong>the</strong> progress now being
made in managing <strong>the</strong> interactions between wild and
cultured salmon must be maintained, enhanced, and given
more urgency to ensure that all aquaculture practices are
conducted in a sustainable manner that does not threaten
wild stocks. They <strong>the</strong>refore agreed to hold a third