CP32-93-2012-3-eng.pdf

Cohen Commission of Inquiry into the Decline of Sockeye Salmon in the Fraser River • Volume 3
chinook, and coho. Dr. Richard Beamish, retired
research scientist, DFO, testified that there is evidence
of hatchery–wild interactions among various
salmon species, although whether there could be
a long-term substantial reduction in production is
less clear among the scientific community. 91
At the hearings on habitat enhancement and
restoration, Dr. Peterman provided evidence that
the body size of adult sockeye salmon decreases as
the abundance of competitors increases, and that
the survival rate of sockeye salmon can decrease
as the abundance of pink salmon competitors
increases. 92 He testified that there is a pressing
need for research into the potential interactions
between enhanced and wild fish. Additionally,
at the hearings on the marine environment,
Dr. Stewart McKinnell, lead author of Technical
Report 4, Marine Ecology, told me that, when the
abundance of fish is high in the North Pacific, the
mean size of sockeye tends to be low. According to
this report, the sea provides only limited amounts
of food for growing sockeye salmon. Thus, Fraser
River sockeye are smaller when the total abundance
of sockeye in the Gulf of Alaska is greater.
Dr. McKinnell said there is some evidence that
Fraser River sockeye are significantly smaller in
brood years that matured in odd-numbered years
(e.g., 2005, 2007, 2009). A reduction in mean size in
odd-numbered years may be a consequence of the
competition for food with pink salmon during the
period of overlap in the Gulf of Alaska.
However, Carol Cross, manager, Strategic
Initiatives, Salmonid Enhancement Program,
testified that neither the Salmonid Enhancement
Program nor DFO Science was, at the time of the
hearings, looking into the effects of competition
between wild and hatchery salmon in the marine
environment. 93 In her view, such studies are complex
and large, requiring significant resources, and
there is a limited capacity to undertake them. 94 She
added that the Salmonid Enhancement Program
recently asked DFO Science to consider a study
to determine the carrying capacity for salmonids
in the Strait of Georgia, in order to aid production
planning decisions at hatchery facilities there. 95 At
the time of the hearings in May 2011, this study had
not yet been designed.
As noted earlier, the precautionary principle
addresses situations involving risk and scientific
uncertainty. The evidence satisfies me that
interactions between Fraser River sockeye salmon
and enhanced fish in the marine environment do
pose a risk of serious harm to Fraser River sockeye.
However, in the absence of a risk assessment, it is
not possible to quantify the likelihood of the potential
harm. Further, despite the evidence that salmon
enhancement poses a risk to Fraser River sockeye
marine survival and that DFO is aware of the nature
of this risk, the department does not account for
this risk in its management of the fishery.
In contrast to the evidence that salmonid
enhancement poses a risk to Fraser River sockeye,
throughout the hearings I heard evidence of the
benefits to sockeye of habitat enhancement and restoration.
I question, therefore, whether the department’s
prioritizing of salmonid enhancement over
habitat enhancement and restoration is consistent
with its conservation mandate. It is important that
DFO undertake a risk assessment without further
delay so a decision can be made on the future of salmonid
enhancement facilities, including whether
they should be maintained.
In making the above findings about the risk
posed by salmonid enhancement, I recognize
that there may be a distinction between salmonid
enhancement for the purpose of producing fish to
sustain commercial and/or recreational harvest
and enhancement for conservation purposes. In
my view, the Wild Salmon Policy signalled a partial
shift in the department’s rationale from enhancement
for fisheries purposes to enhancement as a
means of rebuilding those Conservation Units that
have an unacceptable chance of extirpation. 96 The
policy provides that the enhancement program will
continue to evolve toward a greater emphasis on
community stewardship, habitat restoration, and
rebuilding of priority Conservation Units. Although
hatchery production solely for conservation
purposes may not pose the same risk of harm that
large numbers of enhanced salmon for fisheries
may pose, the risk to Fraser River sockeye of either
type of hatchery production was, at the time of
the hearings, unknown. Therefore, DFO should
assess the risk of salmonid enhancement for both
conservation and fisheries purposes.
Finally, I recognize that the management of
any risk posed by salmonid enhancement to Fraser
River sockeye will likely require international cooperation.
For example, in 2008, Canada released
330 million hatchery salmon, but releases of salmon
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