Basic HTML Version
12
• Tagging experiments are conducted
to understand movement patterns
and determine if fish can be managed
as one population or as multiple
populations that require more
localized management.
Scientists combine
views from all of these
“windows” in statistical
models that estimate
the mass and size
composition of fish
populations. Fishing
can be “turned off”
in these models to
estimate what the condi-
tion of the fish population
might have been in the
absence of fishing given the
observed variability in the ocean
environment. The ratio of the fished
to unfished biomass is then interpreted
as a measure of the impact of fishing.
Fish population status
is reviewed annually.
• by the Science and Statistical Com-
mittee of the Western Pacific Regional
Fishery Management Council
• by the Scientific Committee of the
Western and Central Pacific Fisheries
Commission, and
• by the International Scientific
Committee for Tuna and Tuna-Like
Species in the North Pacific Ocean
Scientists review
current and
projected fish
populations’ status
and advise RFMOs
(WCPFC, IATTC)
whether fishing
is at a sustainable
level or reaching
an unacceptable
level (“overfishing”)
with a population
trajectory toward
an overfished state
if corrective actions
are not taken.
Each year, the Western Pacific Fishery
Management Council prepares an
annual report on the status of U.S.
Pacific pelagic fisheries. This report
fulfills the requirement of NOAA Fisheries
for annual Status and Assessment
of Fisheries Evaluation
(SAFE) reports on
federally-managed
fisheries. It
summarizes
the status of
fish populations
harvested by
Hawaii longline
and other pelagic
fisheries. It also
makes recommen-
dations for corrective
actions to resolve any
overfishing or overfished issues in
these fisheries, as required by the
Magnuson-Stevens Fishery Conserva-
tion and Management Act.
When is fishing “Sustainable” ?
• When fish population losses due to
fishing and natural factors are replen-
ished or surpassed by population gains
through the addition of young fish.
• Fishery scientists estimate a target
catch of fish or level of fishing that
will allow natural replenishment of
the fish population.
• Fishery managers aim to keep fish
catch or the level of fishing below this
target, as adjusted based on socio-
economic and environmental factors.
“Do the right thing”
Hawaii fisheries managers do not wait
for international action to address over-
fishing issues. Under national standard
guidelines of the Magnuson-Stevens
Fishery Conservation and Management
Act (MSA) (50 CFR 600.310), the Western
Pacific Regional Fishery Management
Council must take corrective action
immediately in the form of a Fishery
Management Plan amendment or
proposed regulations when it has been
determined that:
STATUS OF FISH
POPULATION
Sustainability factors
1) Fishery Management
2) Status of harvested fish
populations
3) Ecosystem impacts of fishing
How do scientists determine
the status of fish populations?
Scientists examine several “windows”
that provide insight into the life cycles
of open ocean (pelagic) fish populations.
• Fish catch and fishing effort may
provide clues to fish abundance
in specific areas and depth ranges.
Declining catch rates with increasing
fishing effort could indicate problems
in maintaining a desired sustainable
fish population size.
• Size composition of the individual
fish in the catch provides insight into
the ages of the fish in the population.
Declining average fish size or a sharp
increase in the percentage of small
fish in the catch could indicate
problems in maintaining a sustainable
fish population.
Photo: NOAA Observer Program
Pacific
Moonfish
(opah)
NOAA observer measuring tuna
S
ection
3